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Trippler L, Taylor L, Ali MN, Najim SO, Khamis KS, Hattendorf J, Juma S, Ame SM, Kabole F, Ali SM, Knopp S. Test-treat-track-test-treat (5T) approach for Schistosoma haematobium elimination on Pemba Island, Tanzania. BMC Infect Dis 2024; 24:661. [PMID: 38956479 PMCID: PMC11218394 DOI: 10.1186/s12879-024-09549-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 06/21/2024] [Indexed: 07/04/2024] Open
Abstract
BACKGROUND After decades of praziquantel mass drug administration (MDA), several countries approach schistosomiasis elimination. Continuing MDA in largely uninfected populations no longer seems justified. Alternative interventions to maintain the gains or accelerate interruption of transmission are needed. We report results, strengths, and shortcomings of novel test-treat-track-test-treat (5T) interventions in low Schistosoma haematobium prevalence areas on Pemba, Tanzania. METHODS School- and household-based surveys were conducted in 2021 and 2022 to monitor the S. haematobium and microhematuria prevalence and assess the impact of interventions. In 2021, 5T interventions were implemented in 15 low-prevalence areas and included: (i) testing schoolchildren in primary and Islamic schools for microhematuria as a proxy for S. haematobium, (ii) treating positive children, (iii) tracking them to their households and to water bodies they frequented, (iv) testing individuals at households and water bodies, and (v) treating positive individuals. Additionally, test-and-treat interventions were implemented in the 22 health facilities of the study area. RESULTS The S. haematobium prevalence in the school-based survey in 15 low-prevalence implementation units was 0.5% (7/1560) in 2021 and 0.4% (6/1645) in 2022. In the household-based survey, 0.5% (14/2975) and 0.7% (19/2920) of participants were infected with S. haematobium in 2021 and 2022, respectively. The microhematuria prevalence, excluding trace results, in the school-based survey was 1.4% (21/1560) in 2021 and 1.5% (24/1645) in 2022. In the household-based survey, it was 3.3% (98/2975) in 2021 and 5.4% (159/2920) in 2022. During the 5T interventions, the microhaematuria prevalence was 3.8% (140/3700) and 5.8% (34/594) in children in primary and Islamic schools, respectively, 17.1% (44/258) in household members, and 16.7% (10/60) in people at water bodies. In health facilities, 19.8% (70/354) of patients tested microhematuria-positive. CONCLUSIONS The targeted 5T interventions maintained the very low S. haematobium prevalence and proved straightforward and feasible to identify and treat many of the few S. haematobium-infected individuals. Future research will show whether 5T interventions can maintain gains in the longer-term and expedite elimination. TRIAL REGISTRATION ISRCTN, ISCRCTN91431493. Registered 11 February 2020, https://www.isrctn.com/ISRCTN91431493 .
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Affiliation(s)
- Lydia Trippler
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Lyndsay Taylor
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Sarah Omar Najim
- Ivo de Carneri, Wawi, Chake Chake, Pemba, United Republic of Tanzania
| | | | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Saleh Juma
- Neglected Diseases Program, Zanzibar Ministry of Health, Mkoroshoni, Pemba, United Republic of Tanzania
| | - Shaali Makame Ame
- Neglected Diseases Program, Zanzibar Ministry of Health, Lumumba, Unguja, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Diseases Program, Zanzibar Ministry of Health, Lumumba, Unguja, United Republic of Tanzania
| | - Said Mohammed Ali
- Ivo de Carneri, Wawi, Chake Chake, Pemba, United Republic of Tanzania
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland.
- University of Basel, Basel, Switzerland.
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Ndum NC, Trippler L, Mohammed UA, Ali AS, Hattendorf J, Utzinger J, Ali SM, Knopp S. Capacities and needs of health care facilities for schistosomiasis diagnosis and management in elimination settings. Parasit Vectors 2024; 17:263. [PMID: 38886811 PMCID: PMC11184784 DOI: 10.1186/s13071-024-06311-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 04/29/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND Schistosomiasis is a debilitating neglected tropical disease endemic in sub-Saharan Africa. The role of health facilities in the prevention, diagnosis, control, and elimination of schistosomiasis is poorly documented. In a setting targeted for schistosomiasis elimination in Zanzibar, we assessed the prevalence of Schistosoma haematobium among patients seeking care in a health facility and investigated schistosomiasis-related knowledge of staff, and health facilities' capacities and needs for schistosomiasis diagnosis and management. METHODS We conducted a health facility-based mixed-method study on Pemba Island from June to August 2023. Patients aged ≥ 4 years seeking care in four health facilities were screened for S. haematobium infection using urine filtration and reagent strips. Those patients aged ≥ 10 years were additionally interviewed about signs and symptoms. Staff from 23 health facilities responded to a questionnaire assessing knowledge and practices. Ten staff participated in a focus group discussion (FGD) about capacities and needs for schistosomiasis diagnosis and management. RESULTS The prevalence of S. haematobium infection in patients attending the health facilities, as determined by the presence of eggs in urine, was 1.1% (8/712). Microhaematuria was detected in 13.3% (95/712) of the patients using reagent strips. Among patients responding to the questionnaire, pelvic pain, pain during sex, and painful urination were reported by 38.0% (237/623), 6.3% (39/623), and 3.2% (20/623), respectively. Among the health facility staff, 90.0% (44/49) and 87.8% (43/49) identified blood in urine and pelvic pain, respectively, as symptoms of urogenital schistosomiasis, 81.6% (40/49) and 93.9% (46/49) reported collecting a urine sample and pursuing a reagent strip test, respectively, for diagnosis, and 87.8% (43/49) administered praziquantel for treatment. The most reoccurring themes in the FGD were the need for more staff training about schistosomiasis, requests for diagnostic equipment, and the need to improve community response to schistosomiasis services in health facilities. CONCLUSIONS The prevalence of S. haematobium infection in patients seeking care in health facilities in Pemba is very low and similar to what has been reported from recent community-based cross-sectional surveys. The health facility staff had good schistosomiasis-related knowledge and practices. However, to integrate schistosomiasis patient management more durably into routine health facility activities, scalable screening pathways need to be identified and capacities need to be improved by regular staff training, and an unbroken supply of accurate point-of-care diagnostics and praziquantel for the treatment of cases.
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Affiliation(s)
- Naomi C Ndum
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Lydia Trippler
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Ulfat A Mohammed
- Public Health Laboratory-Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Anisa S Ali
- Public Health Laboratory-Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Said M Ali
- Public Health Laboratory-Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland.
- University of Basel, Basel, Switzerland.
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de Jong D, Carrell C, Maganga JK, Mhango L, Shigella PS, Gill M, Shogren R, Mullins B, Warrick JW, Changalucha JM, van Dam GJ, Pham K, Downs JA, Corstjens PLAM. Flow-S: A Field-Deployable Device with Minimal Hands-On Effort to Concentrate and Quantify Schistosoma Circulating Anodic Antigen (CAA) from Large Urine Volumes. Diagnostics (Basel) 2024; 14:820. [PMID: 38667466 PMCID: PMC11048900 DOI: 10.3390/diagnostics14080820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/26/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024] Open
Abstract
A laboratory-based lateral flow (LF) test that utilizes up-converting reporter particles (UCP) for ultrasensitive quantification of Schistosoma circulating anodic antigen (CAA) in urine is a well-accepted test to identify active infection. However, this UCP-LF CAA test requires sample pre-treatment steps not compatible with field applications. Flow, a new low-cost disposable, allows integration of large-volume pre-concentration of urine analytes and LF detection into a single field-deployable device. We assessed a prototype Flow-Schistosoma (Flow-S) device with an integrated UCP-LF CAA test strip, omitting all laboratory-based steps, to enable diagnosis of active Schistosoma infection in the field using urine. Flow-S is designed for large-volume (5-20 mL) urine, applying passive paper-based filtration and antibody-based CAA concentration. Samples tested for schistosome infection were collected from women of reproductive age living in a Tanzania region where S. haematobium infection is endemic. Fifteen negative and fifteen positive urine samples, selected based on CAA levels quantified in paired serum, were analyzed with the prototype Flow-S. The current Flow-S prototype, with an analytical lower detection limit of 1 pg CAA/mL, produced results correlated with the laboratory-based UCP-LF CAA test. Urine precipitates occurred in frozen banked samples and affected accurate quantification; however, this should not occur in fresh urine. Based on the findings of this study, Flow-S appears suitable to replace the urine pre-treatment required for the laboratory-based UCP-LF CAA test, thus allowing true field-based applications with fresh urine samples. The urine precipitates observed with frozen samples, though less important given the goal of testing fresh urines, warrant additional investigation to evaluate methods for mitigation. Flow-S devices permit testing of pooled urine samples with applications for population stratified testing. A field test with fresh urine samples, a further optimized Flow-S device, and larger statistical power has been scheduled.
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Affiliation(s)
- Daniëlle de Jong
- Department of Cell and Chemical Biology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | | | - Jane K. Maganga
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
| | - Loyce Mhango
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
| | - Peter S. Shigella
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
| | - Maddy Gill
- Salus Discovery LLC, Madison, WI 53703, USA
| | | | | | | | - John M. Changalucha
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
| | - Govert J. van Dam
- Department of Parasitology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
| | - Khanh Pham
- Division of Infectious Diseases, Weill Cornell Medicine, New York, NY 10065, USA
| | - Jennifer A. Downs
- Mwanza Intervention Trials Unit/National Institute for Medical Research, Mwanza, Tanzania
- Center for Global Health, Weill Cornell Medicine, New York, NY 10065, USA
- Department of Medicine, Weill Bugando School of Medicine, Mwanza, Tanzania
| | - Paul L. A. M. Corstjens
- Department of Cell and Chemical Biology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
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Nursafingi A, Widjaja J, Widayati AN, Kurniawan A, Lobo LT, Rauf A, Mananta O, Pangaribuan HU. Spatial Cluster Change of Schistosoma japonicum Transmission Foci in Indonesia During the Schistosomiasis Elimination Program. Acta Parasitol 2024; 69:759-768. [PMID: 38416327 DOI: 10.1007/s11686-024-00802-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 01/03/2024] [Indexed: 02/29/2024]
Abstract
PURPOSE The Government of Indonesia committed to eliminating schistosomiasis by 2025. Collaboratively snail control became one of the crucial strategies to ensure that the prevalence of Schistosoma japonicum in Oncomelania hupensis lindoensis reaches zero by the end of the program. This research investigated the spatial cluster change of S. japonicum transmission foci in Indonesia between 2017 and 2021. METHODS We mapped the snail foci, collected the snails, and calculated the snail density. We also conducted laboratory tests to detect the existence of cercariae in the snails. Identified infected snails were used to calculate the infection rate (IR) or snails' prevalence of schistosome cercariae among freshwater snails. We then analysed the spatial cluster using the Getis-Ord Gi* statistic to identify the hot and cold spots. RESULTS The 5-year schistosomiasis elimination program successfully declined 18.84% of the snail foci and reduced 40.37% of the infected snail foci. Local spatial autocorrelation of snail density and infection rate identified that in 2017 and 2021, the number of cold spots decreased by 53.91% and 0%, while hot spots increased by 2.63% and 56.1%. The presence of more hot spots suggests a rise in the number of foci with high snail density and infection rates. The implementation of snail control was not optimal, and the parasite transmission through domestic animals still existed, causing the spatial cluster of hot spots to change during this period. Most hotspots have been observed near settlements, primarily in cocoa plantations, developed and deserted rice fields, grassland, and bush wetlands. CONCLUSION During the schistosomiasis elimination program, the number of hot spots increased while cold spots decreased, and there were notable changes in the geographical distribution of hot spots, indicating a shift in the clustering pattern of schistosomiasis cases. The findings become essential for policymakers, particularly in selecting priority areas for intervention. In the Discussion section, we demonstrated the selection process based on the existence of hot and cold spots. Furthermore, we proposed that enhancing cross-sector integration is crucial, particularly in connection with the management of S. japonicum transmission through domestic animals.
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Affiliation(s)
- Afi Nursafingi
- Research Center for Public Health and Nutrition, National Research and Innovation Agency, Jakarta, Indonesia.
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia.
| | - Junus Widjaja
- Research Center for Public Health and Nutrition, National Research and Innovation Agency, Jakarta, Indonesia
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
| | - Anis Nur Widayati
- Research Center for Public Health and Nutrition, National Research and Innovation Agency, Jakarta, Indonesia
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
| | - Ade Kurniawan
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
| | - Leonardo Taruk Lobo
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
| | - Abdul Rauf
- Central Sulawesi Health Provincial Office, Palu, Indonesia
| | | | - Helena Ullyartha Pangaribuan
- National Institute of Health Research and Development, Ministry of Health, Jakarta, Indonesia
- Center for Biomedical Research, National Research and Innovation Agency, Jakarta, Indonesia
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Lim RM, Arme TM, Pedersen AB, Webster JP, Lamberton PHL. Defining schistosomiasis hotspots based on literature and shareholder interviews. Trends Parasitol 2023; 39:1032-1049. [PMID: 37806786 DOI: 10.1016/j.pt.2023.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 10/10/2023]
Abstract
The World Health Organization (WHO) recently proposed a new operational definition which designates communities with ≥10% prevalence of Schistosoma spp. infection as a persistent hotspot, when, after at least two rounds of high-coverage annual preventive chemotherapy, there is a lack of appropriate reduction. However, inconsistencies and challenges from both biological and operational perspectives remain, making the prescriptive use of this definition difficult. Here, we present a comprehensive analysis of the use of the term 'hotspot' across schistosomiasis research over time, including both literature searches and opinions from a range of stakeholders, to assess the utility and generalisability of the new WHO definition of a persistent hotspot. Importantly, we propose an updated definition based on our analyses.
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Affiliation(s)
- Rivka M Lim
- Institute of Evolution and Ecology, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, Edinburgh, UK.
| | - Thomas M Arme
- School of Biodiversity, One Health and Veterinary Medicine, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Amy B Pedersen
- Institute of Evolution and Ecology, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, Edinburgh, UK
| | - Joanne P Webster
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Hatfield, Herts, UK
| | - Poppy H L Lamberton
- School of Biodiversity, One Health and Veterinary Medicine, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
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Obonyo CO, Were VO, Wamae P, Muok EMO. SCHISTOACT: a protocol for an open-label, five-arm, non-inferiority, individually randomized controlled trial of the efficacy and safety of praziquantel plus artemisinin-based combinations in the treatment of Schistosoma mansoni infection. Trials 2023; 24:763. [PMID: 38012787 PMCID: PMC10683197 DOI: 10.1186/s13063-023-07790-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/07/2023] [Indexed: 11/29/2023] Open
Abstract
BACKGROUND Schistosomiasis control relies on praziquantel for preventive chemotherapy. Alternative drugs are needed for the treatment and control of schistosomiasis. Praziquantel is effective against adult schistosome worms but ineffective against larval stages of the parasite and cannot prevent re-infection or interrupt the transmission of infection. Continued reliance on praziquantel for wide-scale schistosomiasis control will likely accelerate the emergence of drug resistance. Artemisinin derivatives are effective against the juvenile stages but ineffective against adult worms. The SCHISTOACT study aimed to evaluate the efficacy and safety of praziquantel plus one of four artemisinin-based combinations in treating Schistosoma mansoni infection in Kenya. METHODS The SCHISTOACT study is an open-label, head-to-head, five-arm, proof-of-concept, non-inferiority, individually randomized controlled trial with a follow-up of 12 weeks. A total of 540 primary school-aged children from the Mwea area, Kirinyaga County in central Kenya, diagnosed with S. mansoni infection (by Kato-Katz method) are randomly allocated (1:1:1:1:1) to a single dose of praziquantel plus a 3-day course of artesunate-sulfalene/pyrimethamine, or artesunate-amodiaquine, or artesunate plus mefloquine, or dihydroartemisinin-piperaquine, or praziquantel control arm. The primary endpoints are efficacy (cure rate, assessed by microscopy) and safety (adverse events) of each study arm 6 weeks after treatment. Secondary endpoints include cumulative cure rate, egg reduction rate, and re-infection 12 weeks after treatment. The non-inferiority margin is set at - 10 for the risk difference in cure rates between praziquantel and the combined treatment. DISCUSSION This study assesses a strategy for repurposing artemisinin-based combination therapies (ACTs) for treating schistosomiasis. It adopts a head-to-head comparison of four different ACTs to test a non-inferiority hypothesis and to strengthen local capacity to conduct clinical trials for interventions against neglected tropical diseases. TRIAL REGISTRATION Pan-African Clinical Trials Registry PACTR202001919442161 . Retrospectively registered on 6 January 2020.
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Affiliation(s)
- Charles O Obonyo
- Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya.
| | - Vincent O Were
- Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Peter Wamae
- Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Erick M O Muok
- Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
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Trippler L, Knopp S, Welsche S, Webster BL, Stothard JR, Blair L, Allan F, Ame SM, Juma S, Kabole F, Ali SM, Rollinson D, Pennance T. The long road to schistosomiasis elimination in Zanzibar: A systematic review covering 100 years of research, interventions and control milestones. ADVANCES IN PARASITOLOGY 2023; 122:71-191. [PMID: 37657854 DOI: 10.1016/bs.apar.2023.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
Zanzibar is among the few places in sub-Saharan Africa where interruption of Schistosoma transmission seems an achievable goal. Our systematic review identifies and discusses milestones in schistosomiasis research, control and elimination efforts in Zanzibar over the past 100 years. The search in online databases, libraries, and the World Health Organization Archives revealed 153 records published between May 1928 and August 2022. The content of records was summarised to highlight the pivotal work leading towards urogenital schistosomiasis elimination and remaining research gaps. The greatest achievement following 100 years of schistosomiasis interventions and research is undoubtedly the improved health of Zanzibaris, exemplified by the reduction in Schistosoma haematobium prevalence from>50% historically down to<5% in 2020, and the absence of severe morbidities. Experiences from Zanzibar have contributed to global schistosomiasis guidelines, whilst also revealing challenges that impede progression towards elimination. Challenges include: transmission heterogeneity requiring micro-targeting of interventions, post-treatment recrudescence of infections in transmission hotspots, biological complexity of intermediate host snails, emergence of livestock Schistosoma species complicating surveillance whilst creating the risk for interspecies hybridisation, insufficient diagnostics performance for light intensity infections and female genital schistosomiasis, and a lack of acceptable sanitary alternatives to freshwater bodies. Our analysis of the past revealed that much can be achieved in the future with practical implementation of integrated interventions, alongside operational research. With continuing national and international commitments, interruption of S. haematobium transmission across both islands is within reach by 2030, signposting the future demise of urogenital schistosomiasis across other parts of sub-Saharan Africa.
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Affiliation(s)
- Lydia Trippler
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland.
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | | | - Bonnie L Webster
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom
| | | | | | - Fiona Allan
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom; University of St Andrews, St Andrews, United Kingdom
| | - Shaali Makame Ame
- Neglected Diseases Programme, Zanzibar Ministry of Health, Lumumba, Unguja, United Republic of Tanzania
| | - Saleh Juma
- Neglected Diseases Programme, Zanzibar Ministry of Health, Mkoroshoni, Pemba, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Diseases Programme, Zanzibar Ministry of Health, Lumumba, Unguja, United Republic of Tanzania
| | - Said Mohammed Ali
- Public Health Laboratory - Ivo de Carneri, Wawi, Chake Chake, Pemba, United Republic of Tanzania
| | - David Rollinson
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom; Global Schistosomiasis Alliance, London, United Kingdom
| | - Tom Pennance
- Natural History Museum, London, United Kingdom; London Centre for Neglected Tropical Disease Research, London, United Kingdom; Western University of Health Sciences, Lebanon, OR, United States.
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Torres-Vitolas CA, Trienekens SCM, Zaadnoordijk W, Gouvras AN. Behaviour change interventions for the control and elimination of schistosomiasis: A systematic review of evidence from low- and middle-income countries. PLoS Negl Trop Dis 2023; 17:e0011315. [PMID: 37163556 DOI: 10.1371/journal.pntd.0011315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 05/22/2023] [Accepted: 04/16/2023] [Indexed: 05/12/2023] Open
Abstract
BACKGROUND For the last two decades, schistosomiasis control efforts have focussed on preventive treatment. The disease, however, still affects over 200 million people worldwide. Behaviour change (BC) interventions can strengthen control by interrupting transmission through modifying exposure behaviour (water contact) or transmission practices (open urination/defaecation); or through fostering treatment seeking or acceptance. This review examines these interventions to assess their effectiveness in modifying risk practices and affecting epidemiological trends. METHODOLOGY/PRINCIPAL FINDINGS A systematic multi-database literature search (PROSPERO CRD42021252368) was conducted for peer-reviewed publications released at any time before June 2021 assessing BC interventions for schistosomiasis control in low- and middle-income countries. 2,593 unique abstracts were identified, 66 were assigned to full text review, and 32 met all inclusion criteria. A typology of intervention models was outlined according to their use of behaviour change techniques and overarching rationale: health education (HEIs), social-environmental (SEIs), physical-environmental (PEIs), and incentives-centred interventions (ICIs). Available evidence does not allow to identify which BC approach is most effective in controlling risk behaviour to prevent schistosomiasis transmission. HEIs' impacts were observed to be limited by structural considerations, like infrastructure underdevelopment, economic obligations, socio-cultural traditions, and the natural environment. SEIs may address those challenges through participatory planning and implementation activities, which enable social structures, like governance and norms, to support BC. Their effects, however, appear context-sensitive. The importance of infrastructure investments was highlighted by intervention models. To adequately support BC, however, they require users' inputs and complementary services. Whilst ICIs reported positive impacts on treatment uptake, there are cost-effectiveness and sustainability concerns. Evaluation studies yielded limited evidence of independent epidemiological impacts from BC, due to limited use of suitable indicators and comparators. There was indicative evidence, however, that BC projects could sustain gains through treatment campaigns. CONCLUSIONS/SIGNIFICANCE There is a need for integrated interventions combining information provision, community-based planning, and infrastructure investments to support BC for schistosomiasis control. Programmes should carefully assess local conditions before implementation and consider that long-term support is likely needed. Available evidence indicates that BC interventions may contribute towards schistosomiasis control when accompanied by treatment activities. Further methodologically robust evidence is needed to ascertain the direct epidemiological benefits of BC.
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Affiliation(s)
- Carlos A Torres-Vitolas
- Unlimit Health, London, United Kingdom
- School of Public Health, Imperial College London, London, United Kingdom
| | - Suzan C M Trienekens
- School of Biodiversity, One Health and Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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Chanhanga N, Mindu T, Mogaka J, Chimbari M. The Impact of Targeted Treatment and Mass Drug Administration Delivery Strategies on the Prevalence and Intensity of Schistosomiasis in School Aged Children in Africa: A Systematic Review. Infect Drug Resist 2023; 16:2453-2466. [PMID: 37138838 PMCID: PMC10150034 DOI: 10.2147/idr.s395382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 03/16/2023] [Indexed: 05/05/2023] Open
Abstract
Schistosomiasis is a public health problem in more than 78 countries in the world. The disease is most prevalent among children than adults due to their high exposure to infectious water sources. Various interventions such as mass drug administration (MDA), snail control, safe water provision and health education have been implemented independently or jointly to control, reduce and ultimately eliminate Schistosomiasis. This scoping review focused on studies reporting the impact of different delivery strategies of targeted treatment and MDA on the prevalence and intensity of schistosomiasis infection in school aged children in Africa. The review focused on Schistosoma haematobium and Schistosoma mansoni species. A systematic search for eligible literature from peer-reviewed articles was done from Google Scholar, Medline, PubMed and EBSCO host databases. The search yielded twenty-seven peer-reviewed articles. All articles found reported a decrease in the prevalence of schistosomiasis infection. Five studies (18.5%) reported a prevalence change below 40%, eighteen studies (66.7%) reported a change between 40% and 80%, and four studies (14.8%) reported a change above 80%. The infection intensity post-treatment was varied: twenty-four studies reported a decrease, while two studies reported an increase. The review showed that the impact of targeted treatment on the prevalence and intensity of schistosomiasis depended on the frequency at which it was offered, complementary interventions, and its uptake by the target population. Targeted treatment can significantly control the infection burden, but cannot eliminate the disease. Constant MDA programs coupled with preventative and health promotional programs are required to reach the elimination stage.
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Affiliation(s)
- Nathan Chanhanga
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
| | - Tafadzwa Mindu
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
- Correspondence: Tafadzwa Mindu, Email
| | - John Mogaka
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
| | - Moses Chimbari
- School of Nursing and Public Health, University of KwaZulu Natal, Durban, South Africa
- Research and Innovation, Great Zimbabwe University, Masvingo, Zimbabwe
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Pennance T, Neves MI, Webster BL, Gower CM, Knopp S, Khamis IS, Ame SM, Ali SM, Rabone M, Emery A, Allan F, Muhsin MA, Suleiman KR, Kabole F, Walker M, Rollinson D, Webster JP. Potential drivers for schistosomiasis persistence: Population genetic analyses from a cluster-randomized urogenital schistosomiasis elimination trial across the Zanzibar islands. PLoS Negl Trop Dis 2022; 16:e0010419. [PMID: 36215334 PMCID: PMC9584424 DOI: 10.1371/journal.pntd.0010419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 10/20/2022] [Accepted: 09/13/2022] [Indexed: 11/08/2022] Open
Abstract
The World Health Organization's revised NTD Roadmap and the newly launched Guidelines target elimination of schistosomiasis as a public health problem in all endemic areas by 2030. Key to meeting this goal is elucidating how selective pressures imposed by interventions shape parasite populations. Our aim was to identify any differential impact of a unique cluster-randomized tri-armed elimination intervention (biannual mass drug administration (MDA) applied alone or in association with either mollusciciding (snail control) or behavioural change interventions) across two Zanzibarian islands (Pemba and Unguja) on the population genetic composition of Schistosoma haematobium over space and time. Fifteen microsatellite loci were used to analyse individual miracidia collected from infected individuals across islands and intervention arms at the start (2012 baseline: 1,522 miracidia from 176 children; 303 from 43 adults; age-range 6-75, mean 12.7 years) and at year 5 (2016: 1,486 miracidia from 146 children; 214 from 25 adults; age-range 9-46, mean 12.4 years). Measures of genetic diversity included allelic richness (Ar), Expected (He) and Observed heterozygosity (Ho), inbreeding coefficient (FST), parentage analysis, estimated worm burden, worm fecundity, and genetic sub-structuring. There was little evidence of differential selective pressures on population genetic diversity, inbreeding or estimated worm burdens by treatment arm, with only the MDA+snail control arm within Unguja showing trends towards reduced diversity and altered inbreeding over time. The greatest differences overall, both in terms of parasite fecundity and genetic sub-structuring, were observed between the islands, consistent with Pemba's persistently higher mean infection intensities compared to neighbouring Unguja, and within islands in terms of infection hotspots (across three definitions). These findings highlight the important contribution of population genetic analyses to elucidate extensive genetic diversity and biological drivers, including potential gene-environmental factors, that may override short term selective pressures imposed by differential disease control strategies. Trial Registration: ClinicalTrials.gov ISRCTN48837681.
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Affiliation(s)
- Tom Pennance
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
| | - M. Inês Neves
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - Bonnie L. Webster
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
| | - Charlotte M. Gower
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - Stefanie Knopp
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Iddi Simba Khamis
- Neglected Diseases Programme, Ministry of Health, Zanzibar, United Republic of Tanzania
| | - Shaali M. Ame
- Public Health Laboratory—Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Said M. Ali
- Public Health Laboratory—Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Muriel Rabone
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
| | - Aidan Emery
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
| | - Fiona Allan
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
| | - Mtumweni Ali Muhsin
- Neglected Diseases Programme, Ministry of Health, Zanzibar, United Republic of Tanzania
| | | | - Fatama Kabole
- Neglected Diseases Programme, Ministry of Health, Zanzibar, United Republic of Tanzania
| | - Martin Walker
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, The Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
| | - Joanne P. Webster
- London Centre for Neglected Tropical Disease Research (LCNTDR), London, United Kingdom
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
- * E-mail:
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Mazigo HD, Samson A, Lambert VJ, Kosia AL, Ngoma DD, Murphy R, Kabole FM, Matungwa DJ. Healthcare Workers’ Low Knowledge of Female Genital Schistosomiasis and Proposed Interventions to Prevent, Control, and Manage the Disease in Zanzibar. Int J Public Health 2022; 67:1604767. [PMID: 36188750 PMCID: PMC9520356 DOI: 10.3389/ijph.2022.1604767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 08/10/2022] [Indexed: 11/13/2022] Open
Abstract
Objectives: This study was conducted to explore healthcare workers’ knowledge of female genital schistosomiasis (FGS) and describe proposed interventions to raise awareness about FGS and strengthen healthcare facilities’ capacity to manage FGS cases.Methods: We conducted four cross-sectional focus group discussions and 16 key informant interviews with purposively selected healthcare workers in Zanzibar. Discussions and interviews were digitally recorded, transcribed, and analyzed using NVivo software.Results: Most participants had limited or no knowledge of FGS and lacked skills for managing it. They confused FGS with urogenital schistosomiasis and thought it was sexually transmitted. A few participants knew about FGS and associated it with Human Immunodeficiency Virus (HIV), ectopic pregnancy, cervical cancer, and infertility. To prevent and control FGS, participants proposed interventions targeting communities (including community-based health education) and the healthcare system (including training healthcare workers on FGS).Conclusion: Healthcare workers lacked knowledge of and skills for managing FGS. Besides, healthcare facilities had no diagnostic capacity to manage FGS. Along with on-going interventions to break S. haematobium transmission and eventually eliminate urogenital schistosomiasis in Zanzibar, we recommend training healthcare workers on FGS and equip healthcare facilities with medical equipment and supplies for managing FGS.
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Affiliation(s)
- Humphrey D. Mazigo
- Department of Parasitology and Entomology, Weill Bugando School of Medicine, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Anna Samson
- Department of Behavioral Sciences, School of Public Health, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Valencia J. Lambert
- Center for Global Health, Weill Cornell Medicine, New York, NY, United States
| | - Agnes L. Kosia
- School of Nursing, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Deogratias D. Ngoma
- Accelerating the Sustainable Control and Elimination of Neglected Tropical Diseases, Crown Agents, London, United Kingdom
| | | | | | - Dunstan J. Matungwa
- Department of Sexual and Reproductive Health, National Institute for Medical Research, Mwanza, Tanzania
- Department of Anthropology, School of Arts and Sciences, Rutgers University, New Brunswick, NJ, United States
- *Correspondence: Dunstan J. Matungwa,
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Fine-scale-mapping of Schistosoma haematobium infections at the school and community levels and intermediate host snail abundance in the north of Pemba Island: baseline cross-sectional survey findings before the onset of a 3-year intervention study. Parasit Vectors 2022; 15:292. [PMID: 35974353 PMCID: PMC9380971 DOI: 10.1186/s13071-022-05404-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
Background Schistosomiasis elimination has gained renewed priority in the WHO guidance documents published in 2020 and 2022. The SchistoBreak project, implemented in Pemba, Tanzania between 2020 and 2024, aims to assess new tools and strategies for shifting from elimination as a public health problem towards interruption of transmission. Here we report our baseline findings and discuss implications for future interventions. Methods In 2020, human water contact sites (HWCSs) in the study area were geolocated and snail surveys were conducted. A parasitological and questionnaire cross-sectional baseline survey was implemented in 20 communities and their 16 primary schools between November 2020 and February 2021. Urine samples were collected at the school and household levels from individuals aged ≥ 4 years. Schistosoma haematobium infection was detected by urine filtration microscopy. Snail, parasitological and questionnaire-derived data were analyzed descriptively, spatially and with generalized estimated equation models. Results The intermediate host snail Bulinus globosus was detected in 19.8% (33/167) of HWCSs. The overall S. haematobium prevalence was 1.2% (26/2196) in school-aged children and 0.8% (31/3893) in community members, with 0.2% (4/2196) and 0.1% (3/3893) heavy-intensity infections, respectively. Children who studied < 1 km away from HWCSs with B. globosus had significantly higher odds for a S. haematobium infection than those attending a school located > 2 km away (odds ratio [OR]: 5.0; 95% confidence interval [CI]: 2.3–11.1). Individuals living in a house located < 1 km away from HWCSs with B. globosus had higher odds than those residing in > 2 km distance (OR: 18.0; 95% CI: 2.9–111.0). Self-reported praziquantel treatment coverage was 83.2% (2015/2423) in schoolchildren in the mass drug administration (MDA) conducted in August 2020. Coverage among adult community members was 59.9% (574/958), but only 34.8% (333/958) took praziquantel correctly. Conclusions While the S. haematobium prevalence is very low in Pemba, there are many HWCSs with B. globosus situated close to schools or houses that pose a considerable risk of recrudescence. To maintain and accelerate the progress towards interruption of transmission, targeted and cost-effective interventions that are accepted by the community are needed; for example, snail control plus focal MDA, or test-and-treat in schools and households near infested waterbodies. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-022-05404-6.
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Pennance T, Ame SM, Amour AK, Suleiman KR, Muhsin MA, Kabole F, Ali SM, Archer J, Allan F, Emery A, Rabone M, Knopp S, Rollinson D, Cable J, Webster BL. Transmission and diversity of Schistosoma haematobium and S. bovis and their freshwater intermediate snail hosts Bulinus globosus and B. nasutus in the Zanzibar Archipelago, United Republic of Tanzania. PLoS Negl Trop Dis 2022; 16:e0010585. [PMID: 35788199 PMCID: PMC9286283 DOI: 10.1371/journal.pntd.0010585] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 07/15/2022] [Accepted: 06/14/2022] [Indexed: 11/17/2022] Open
Abstract
Background The Zanzibar Archipelago (Pemba and Unguja islands) is targeted for the elimination of human urogenital schistosomiasis caused by infection with Schistosoma haematobium where the intermediate snail host is Bulinus globosus. Following multiple studies, it has remained unclear if B. nasutus (a snail species that occupies geographically distinct regions on the Archipelago) is involved in S. haematobium transmission on Zanzibar. Additionally, S. haematobium was thought to be the only Schistosoma species present on the Zanzibar Archipelago until the sympatric transmission of S. bovis, a parasite of ruminants, was recently identified. Here we re-assess the epidemiology of schistosomiasis on Pemba and Unguja together with the role and genetic diversity of the Bulinus spp. involved in transmission. Methodology/Principal findings Malacological and parasitological surveys were conducted between 2016 and 2019. In total, 11,116 Bulinus spp. snails were collected from 65 of 112 freshwater bodies surveyed. Bulinus species identification were determined using mitochondrial cox1 sequences for a representative subset of collected Bulinus (n = 504) and together with archived museum specimens (n = 6), 433 B. globosus and 77 B. nasutus were identified. Phylogenetic analysis of cox1 haplotypes revealed three distinct populations of B. globosus, two with an overlapping distribution on Pemba and one on Unguja. For B. nasutus, only a single clade with matching haplotypes was observed across the islands and included reference sequences from Kenya. Schistosoma haematobium cercariae (n = 158) were identified from 12 infected B. globosus and one B. nasutus collected between 2016 and 2019 in Pemba, and cercariae originating from 69 Bulinus spp. archived in museum collections. Schistosoma bovis cercariae (n = 21) were identified from seven additional B. globosus collected between 2016 and 2019 in Pemba. By analysing a partial mitochondrial cox1 region and the nuclear ITS (1–5.8S-2) rDNA region of Schistosoma cercariae, we identified 18 S. haematobium and three S. bovis haplotypes representing populations associated with mainland Africa and the Indian Ocean Islands (Zanzibar, Madagascar, Mauritius and Mafia). Conclusions/Significance The individual B. nasutus on Pemba infected with S. haematobium demonstrates that B. nasutus could also play a role in the local transmission of S. haematobium. We provide preliminary evidence that intraspecific variability of S. haematobium on Pemba may increase the transmission potential of S. haematobium locally due to the expanded intermediate host range, and that the presence of S. bovis complicates the environmental surveillance of schistosome infections. Schistosomiasis is a snail-borne neglected tropical disease caused by parasitic blood flukes of the genus Schistosoma. Human urogenital schistosomiasis is targeted for elimination on the Zanzibar Archipelago, United Republic of Tanzania, with multiple interventions being implemented to curtail transmission of the parasite to humans on the islands since 2012. Environmental surveillance for schistosomiasis transmission by collecting intermediate host snails, checking snails for Schistosoma infection, and preserving collected snails and Schistosoma parasites offers the possibility for molecular analyses to investigate the evolutionary/genetic relationships of both snails and parasites. Schistosome transmission on Zanzibar was believed to involve a single schistosome species (Schistosoma haematobium) transmitted via a single intermediate host species (Bulinus globosus). However, our findings demonstrate the locally established presence of S. bovis, responsible for bovine intestinal schistosomiasis, and an extended intermediate host compatibility of S. haematobium with the snail B. nasutus on Pemba. Increased parasite diversity and intermediate host species compatibility may increase the transmission of Schistosoma species on Zanzibar and stretch resources for public health interventions with the need for Schistosoma species specific surveillance.
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Affiliation(s)
- Tom Pennance
- Department of Science, Natural History Museum, London, United Kingdom
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific–Northwest, Western University of Health Sciences, Lebanon, Oregon, United States of America
- * E-mail:
| | - Shaali Makame Ame
- Public Health Laboratory-Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Amour Khamis Amour
- Public Health Laboratory-Ivo de Carneri, Pemba, United Republic of Tanzania
| | | | - Mtumweni Ali Muhsin
- Neglected Diseases Program, Ministry of Health Zanzibar, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Diseases Program, Ministry of Health Zanzibar, United Republic of Tanzania
| | - Said Mohammed Ali
- Public Health Laboratory-Ivo de Carneri, Pemba, United Republic of Tanzania
| | - John Archer
- Department of Science, Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
| | - Fiona Allan
- Department of Science, Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
- The Scottish Oceans Institute, Gatty Marine Laboratory, University of St Andrews, East Sands, St Andrews, United Kingdom
| | - Aidan Emery
- Department of Science, Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
| | - Muriel Rabone
- Department of Science, Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - David Rollinson
- Department of Science, Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
| | - Joanne Cable
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Bonnie L. Webster
- Department of Science, Natural History Museum, London, United Kingdom
- London Centre for Neglected Tropical Disease Research, London, United Kingdom
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Zdesenko G, Mduluza T, Mutapi F. Pharmacogenetics of Praziquantel Metabolism: Evaluating the Cytochrome P450 Genes of Zimbabwean Patients During a Schistosomiasis Treatment. Front Genet 2022; 13:914372. [PMID: 35754834 PMCID: PMC9213834 DOI: 10.3389/fgene.2022.914372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/17/2022] [Indexed: 11/13/2022] Open
Abstract
Schistosomiasis is a parasitic disease infecting over 236 million people annually, with the majority affected residing on the African continent. Control of this disease is reliant on the drug praziquantel (PZQ), with treatment success dependent on an individual reaching PZQ concentrations lethal to schistosomes. Despite the complete reliance on PZQ to treat schistosomiasis in Africa, the characterization of the pharmacogenetics associated with PZQ metabolism in African populations has been sparse. We aimed to characterize genetic variation in the drug-metabolising cytochrome P450 enzymes (CYPs) and determine the association between each variant and the efficacy of PZQ treatment in Zimbabwean patients exposed to Schistosoma haematobium infection. Genomic DNA from blood samples of 114 case-control Zimbabweans infected with schistosomes were sequenced using the CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5 genes as targets. Bioinformatic tools were used to identify and predict functional effects of detected single nucleotide polymorphisms (SNPs). A random forest (RF) model was then used to assess SNPs most predictive of PZQ efficacy, with a misclassification rate of 29%. SNPs were detected across all six genes, with 70 SNPs identified and multiple functional changes to the CYP enzymes predicted. Only four SNPs were significantly associated with PZQ efficacy using χ2 tests, with rs951840747 (OR: 3.61, p = 0.01) in the CYP1A2 gene having the highest odds of an individual possessing this SNP clearing infection, and rs6976017 (OR: 2.19, p = 0.045) of CYP3A5 determined to be the most predictive of PZQ efficacy via the RF. Only the rs28371702 (CC) genotype (OR: 2.36, p = 0.024) of CYP2D6 was significantly associated with an unsuccessful PZQ treatment. This study adds to the genomic characterization of the diverse populations in Africa and identifies variants relevant to other pharmacogenetic studies crucial for the development and usage of drugs in these populations.
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Affiliation(s)
- Grace Zdesenko
- Ashworth Laboratories, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom.,Ashworth Laboratories, NIHR Global Health Research Unit Tackling Infections to Benefit Africa (TIBA), University of Edinburgh, Edinburgh, United Kingdom
| | - Takafira Mduluza
- Ashworth Laboratories, NIHR Global Health Research Unit Tackling Infections to Benefit Africa (TIBA), University of Edinburgh, Edinburgh, United Kingdom.,Department of Biochemistry, University of Zimbabwe, Harare, Zimbabwe
| | - Francisca Mutapi
- Ashworth Laboratories, Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom.,Ashworth Laboratories, NIHR Global Health Research Unit Tackling Infections to Benefit Africa (TIBA), University of Edinburgh, Edinburgh, United Kingdom
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Impact of preventive chemotherapy on transmission of soil-transmitted helminth infections in Pemba Island, United Republic of Tanzania, 1994–2021. PLoS Negl Trop Dis 2022; 16:e0010477. [PMID: 35759453 PMCID: PMC9236265 DOI: 10.1371/journal.pntd.0010477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 05/09/2022] [Indexed: 11/19/2022] Open
Abstract
Soil-transmitted helminth (STH) infections cause significant morbidity in children and women of reproductive age. The World Health Organization (WHO) recommends preventive chemotherapy (PC) of at-risk populations with anthelminthics to control these infections. Historically, STH are very intensively transmitted in Pemba Island (Zanzibar). A survey conducted in 1994 in 12 schools estimated a STH prevalence near to 100%. This extremely high prevalence induced the introduction of PC in the island; initially, however, PC was not regularly administered because of difficulties linked to drug procurement. A second STH survey, conducted in 2011, in 24 schools estimated a prevalence of STH of 89%; after this survey, PC was regularly administered until 2018. We conducted a survey in 2021 using the same method as that used in 2011. The prevalence of STH was evaluated at 80% (95% CI 78.1–81.5) and most of the STH cases were due to Trichuris trichiura. More than 32% (95% CI 30.3–34.0) of the children investigated had infections of moderate or heavy intensity. PC has been conducted for over 25 years in Pemba Island. However, despite its beneficial impact, both the prevalence and the intensity of STH infections remain high, and the intervention has been insufficient in controlling STH morbidity. This is probably due to a combination of irregular PC, climatic conditions favourable to STH transmission, the low sensitivity of T. trichiura to benzimidazoles, high population density and poor sanitation. Improvement of sanitation coverage remains a key measure to permanently reduce the prevalence and intensity of STH. Possible changes to the present PC approaches to better control STH in Pemba would be (i) to assure high coverage in all schools, (ii) to use mebendazole instead of albendazole given its better activity on T. trichiura and (iii) to use a combination of ivermectin and mebendazole to further increase anthelminthic efficacy on T. trichiura. A survey conducted in 1994 in school aged children showed that soil-transmitted helminth were very intensively transmitted in Pemba Island (Zanzibar) with prevalence near to 100%. Between 1994 and 2011 several rounds of administration of anthelminthic were organized and a second survey was conducted in 2011 showing a decrease of prevalence and intensity of infection. The present paper reports the results of a third survey conducted in 2021 showing a further decline of the prevalence and a persistence of T. trichiura as the more prevalent parasite (in 1994 hookworms were the most transmitted STH). The interventions conducted until now where not sufficient to eliminate the morbidity caused by these parasites and it is suggested to include ivermectin in the anthelminthic distributed periodically.
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Naqvi FA, Das JK, Salam RA, Raza SF, Lassi ZS, Bhutta ZA. Interventions for Neglected Tropical Diseases Among Children and Adolescents: A Meta-analysis. Pediatrics 2022; 149:186947. [PMID: 35503336 DOI: 10.1542/peds.2021-053852e] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/16/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Neglected tropical diseases (NTDs) are a group of communicable diseases affecting the poorest populations around the world. OBJECTIVE To assess the effectiveness of interventions, including mass drug administration (MDA), water, sanitation, and hygiene (WASH), vector control, health education, and micronutrients supplementation, for NTDs among children and adolescents. METHODS We conducted a literature search on the Cochrane Controlled Trials Register, Medline, and other databases until December 2020. We included randomized controlled trials and quasi-experimental studies conducted among children and adolescents. Two authors independently screened studies for relevance. Two authors independently extracted data, assessed the risk of bias, performed metaanalysis, and rated the quality of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation. RESULTS We included 155 studies (231 articles) involving 262 299 participants. For soil-transmitted helminthiasis, MDA may reduce the prevalence of Ascaris, Trichuris, and hookworm by 58%, 36%, and 57%, respectively. We are uncertain of the effect of health education, WASH, and iron supplementation on soil-transmitted helminthiasis prevalence. For Schistosomiasis, health education probably reduces the intensity and prevalence of S. mansoni, whereas micronutrient supplementation may reduce anemia prevalence and the infection intensity of S. hematobium compared with no supplementation. We are uncertain of the effect of MDA and vector control on Schistosomiasis outcomes. For trachoma, health education probably reduces the prevalence of active Trachoma, whereas we are uncertain of the effect of MDA, WASH, and vector control on Trachoma outcomes. There is limited data on the effectiveness of interventions for NTDs targeting children and adolescents. CONCLUSION Future studies are needed to evaluate the relative effectiveness and cost-effectiveness of various interventions specifically targeting children and adolescents.
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Affiliation(s)
- Fatima Abbas Naqvi
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Jai K Das
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Rehana A Salam
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Syeda Fatima Raza
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan
| | - Zohra S Lassi
- Robinson Research Institute, the University of Adelaide, Adelaide, Australia.,Adelaide Medical School, The University of Adelaide, Adelaide, Australia
| | - Zulfiqar A Bhutta
- Division of Women and Child Health, Aga Khan University Hospital, Karachi, Pakistan.,Centre for Global Child Health, The Hospital for Sick Children (SickKids), Toronto, Ontario, Canada
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Young ND, Kinkar L, Stroehlein AJ, Korhonen PK, Stothard JR, Rollinson D, Gasser RB. Mitochondrial genome of Bulinus truncatus (Gastropoda: Lymnaeoidea): Implications for snail systematics and schistosome epidemiology. CURRENT RESEARCH IN PARASITOLOGY & VECTOR-BORNE DISEASES 2022; 1:100017. [PMID: 35284876 PMCID: PMC8906109 DOI: 10.1016/j.crpvbd.2021.100017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/10/2021] [Accepted: 02/11/2021] [Indexed: 11/29/2022]
Abstract
Many freshwater snails of the genus Bulinus act as intermediate hosts in the life-cycles of schistosomes in Africa and adjacent regions. Currently, 37 species of Bulinus representing four groups are recognised. The mitochondrial cytochrome c oxidase subunit 1 (cox1) gene has shown utility for identifying and differentiating Bulinus species and groups, but taxonomic relationships based on genetic data are not entirely consistent with those inferred using morphological and biological features. To underpin future systematic studies of members of the genus, we characterised here the mitochondrial genome of Bulinus truncatus (from a defined laboratory strain) using a combined second- and third-generation sequencing and informatics approach, enabling taxonomic comparisons with other planorbid snails for which mitochondrial (mt) genomes were available. Analyses showed consistency in gene order and length among mitochondrial genomes of representative planorbid snails, with the lowest and highest nucleotide diversities being in the cytochrome c oxidase and nicotinamide dehydrogenase subunit genes, respectively. This first mt genome for a representative of the genus Bulinus should provide a useful resource for future investigations of the systematics, population genetics, epidemiology and/or ecology of Bulinus and related snails. The sequencing and informatic workflow employed here should find broad applicability to a range of other snail intermediate hosts of parasitic trematodes.
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Affiliation(s)
- Neil D Young
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Liina Kinkar
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Andreas J Stroehlein
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Pasi K Korhonen
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - J Russell Stothard
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David Rollinson
- Department of Life Sciences, Natural History Museum, London, UK.,London Centre for Neglected Tropical Disease Research, London, UK
| | - Robin B Gasser
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
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18
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Fergus CA, Ozunga B, Okumu N, Parker M, Kamurari S, Allen T. Shifting the dynamics: implementation of locally driven, mixed-methods modelling to inform schistosomiasis control and elimination activities. BMJ Glob Health 2022; 7:e007113. [PMID: 35110273 PMCID: PMC8811568 DOI: 10.1136/bmjgh-2021-007113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 01/03/2022] [Indexed: 11/27/2022] Open
Abstract
INTRODUCTION The integration of more diverse perspectives into the development of evidence for decision-making has been elusive, despite years of rhetoric to the contrary. This has led to cycles of population-based health interventions which have not delivered the promised results. The WHO most recently set a target for schistosomiasis elimination by 2030 and called for cross-cutting approaches to be driven by endemic countries themselves. The extent to which elimination is feasible within the time frame has been a subject of debate. METHODS Systems maps were developed through participatory modelling activities with individuals working on schistosomiasis control and elimination activities from the village through national levels in Uganda. These maps were first synthesised, then used to frame the form and content of subsequent mathematical modelling activities, and finally explicitly informed model parameter specifications for simulations, using the open-source SCHISTOX model, driven by the participants. RESULTS Based on the outputs of the participatory modelling, the simulation activities centred around reductions in water contact. The results of the simulations showed that mass drug administration, at either the current or target levels of coverage, combined with water contact reduction activities, achieved morbidity control in high prevalence Schistosoma mansoni settings, while both morbidity control and elimination were achieved in high prevalence S. haematobium settings within the 10-year time period. CONCLUSION The combination of participatory systems mapping and individual-based modelling was a rich strategy which explicitly integrated the perspectives of national and subnational policymakers and practitioners into the development of evidence. This strategy can serve as a method by which individuals who have not been traditionally included in modelling activities, and do not hold positions or work in traditional centres of power, may be heard and truly integrated into the development of evidence for decision-making in global health.
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Affiliation(s)
- Cristin Alexis Fergus
- Firoz Lalji Institute for Africa, LSE, London, UK
- Department of International Development, LSE, London, UK
| | - Bono Ozunga
- Vector Control Division, Republic of Uganda Ministry of Health, Mayuge, Uganda
| | - Noah Okumu
- Vector Control Division, Republic of Uganda Ministry of Health, Pakwach, Uganda
| | - Melissa Parker
- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, UK
| | | | - Tim Allen
- Firoz Lalji Institute for Africa, LSE, London, UK
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19
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A descriptive qualitative case study of the experiences, perceptions and attitudes of pregnant women on Unguja island, Zanzibar, towards antischistosomal treatment. Acta Trop 2022; 225:106143. [PMID: 34562430 PMCID: PMC8646856 DOI: 10.1016/j.actatropica.2021.106143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 08/17/2021] [Accepted: 09/12/2021] [Indexed: 11/23/2022]
Abstract
Women were enthusiastic about keeping healthy during pregnancy. Women strongly valued high quality antenatal care and were encouraged to attend clinics by their families and community members. Women demonstrated poor retention of knowledge about schistosomiasis from school. The majority of women interviewed had missed mass drug administration rounds of praziquantel due to pregnancy or concerns about side effects. Women were unanimously agreeable to taking praziquantel during pregnancy if advised to do so by a healthcare professional.
Many countries exclude pregnant and lactating women from mass drug administration (MDA) programmes with praziquantel against schistosomiasis due to historic safety concerns over drug use during gestation and breast feeding. More than 10 years of empirical evidence from the field and a growing body of dedicated research has prompted the World Health Organisation and schistosomiasis control initiatives to advocate the inclusion of this vulnerable group into MDA. This qualitative descriptive case study explored, over a five-week period, the subjective experiences, perceptions, opinions, and attitudes of pregnant women attending government supported clinics on Unguja island, United Republic of Tanzania, towards praziquantel use during pregnancy in MDA programmes. The aim of the study was to identify and determine how to overcome potential barriers to effective use of MDA medications during pregnancy. Additionally, it was to determine trusted communication channels for future messaging and discover behavioural and community opportunities to increase participation of pregnant women in future MDA efforts. A 60 min, semi-structured qualitative interview was undertaken with 25 pregnant women recruited from 4 health centres on Unguja along with testing for Schistosoma haematobium infection. Using a modified-grounded theory approach, narrative data were transcribed, coded and analysed using a thematic analysis of the emergent themes. Women reported that they rely on traditional home remedies to stay healthy during pregnancy. Influenced by their mothers, husbands and neighbours, women predominately made medication choices during pregnancy and breastfeeding based on what they heard at home. Most women had been excluded from government MDA programmes in the past due to pregnancy. Women valued healthcare services for antenatal education and pregnancy advice. Women reported they would trust and follow direction from healthcare providers about taking praziquantel during pregnancy. Antenatal clinics offer an excellent opportunity to educate and expand praziquantel treatment to this cohort. Efforts should be augmented with training for providers and behavioural education for the community as a whole and family members of pregnant women.
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20
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Lund AJ, Wade KJ, Nikolakis ZL, Ivey KN, Perry BW, Pike HNC, Paull SH, Liu Y, Castoe TA, Pollock DD, Carlton EJ. Integrating genomic and epidemiologic data to accelerate progress toward schistosomiasis elimination. eLife 2022; 11:79320. [PMID: 36040013 PMCID: PMC9427098 DOI: 10.7554/elife.79320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 08/11/2022] [Indexed: 11/13/2022] Open
Abstract
The global community has adopted ambitious goals to eliminate schistosomiasis as a public health problem, and new tools are needed to achieve them. Mass drug administration programs, for example, have reduced the burden of schistosomiasis, but the identification of hotspots of persistent and reemergent transmission threaten progress toward elimination and underscore the need to couple treatment with interventions that reduce transmission. Recent advances in DNA sequencing technologies make whole-genome sequencing a valuable and increasingly feasible option for population-based studies of complex parasites such as schistosomes. Here, we focus on leveraging genomic data to tailor interventions to distinct social and ecological circumstances. We consider two priority questions that can be addressed by integrating epidemiological, ecological, and genomic information: (1) how often do non-human host species contribute to human schistosome infection? and (2) what is the importance of locally acquired versus imported infections in driving transmission at different stages of elimination? These questions address processes that can undermine control programs, especially those that rely heavily on treatment with praziquantel. Until recently, these questions were difficult to answer with sufficient precision to inform public health decision-making. We review the literature related to these questions and discuss how whole-genome approaches can identify the geographic and taxonomic sources of infection, and how such information can inform context-specific efforts that advance schistosomiasis control efforts and minimize the risk of reemergence.
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Affiliation(s)
- Andrea J Lund
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado AnschutzAuroraUnited States
| | - Kristen J Wade
- Department of Biochemistry & Molecular Genetics, University of Colorado School of MedicineAuroraUnited States
| | - Zachary L Nikolakis
- Department of Biology, University of Texas at ArlingtonArlingtonUnited States
| | - Kathleen N Ivey
- Department of Biology, University of Texas at ArlingtonArlingtonUnited States
| | - Blair W Perry
- Department of Biology, University of Texas at ArlingtonArlingtonUnited States
| | - Hamish NC Pike
- Department of Biochemistry & Molecular Genetics, University of Colorado School of MedicineAuroraUnited States
| | - Sara H Paull
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado AnschutzAuroraUnited States
| | - Yang Liu
- Sichuan Centers for Disease Control and PreventionChengduChina
| | - Todd A Castoe
- Department of Biology, University of Texas at ArlingtonArlingtonUnited States
| | - David D Pollock
- Department of Biochemistry & Molecular Genetics, University of Colorado School of MedicineAuroraUnited States
| | - Elizabeth J Carlton
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado AnschutzAuroraUnited States
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21
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Rinaldo D, Perez-Saez J, Vounatsou P, Utzinger J, Arcand JL. The economic impact of schistosomiasis. Infect Dis Poverty 2021; 10:134. [PMID: 34895355 PMCID: PMC8667389 DOI: 10.1186/s40249-021-00919-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/04/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The economic impact of schistosomiasis and the underlying tradeoffs between water resources development and public health concerns have yet to be quantified. Schistosomiasis exerts large health, social and financial burdens on infected individuals and households. While irrigation schemes are one of the most important policy responses designed to reduce poverty, particularly in sub-Saharan Africa, they facilitate the propagation of schistosomiasis and other diseases. METHODS We estimate the economic impact of schistosomiasis in Burkina Faso via its effect on agricultural production. We create an original dataset that combines detailed household and agricultural surveys with high-resolution geo-statistical disease maps. We develop new methods that use the densities of the intermediate host snails of schistosomiasis as instrumental variables together with panel, spatial and machine learning techniques. RESULTS We estimate that the elimination of schistosomiasis in Burkina Faso would increase average crop yields by around 7%, rising to 32% for high infection clusters. Keeping schistosomiasis unchecked, in turn, would correspond to a loss of gross domestic product of approximately 0.8%. We identify the disease burden as a shock to the agricultural productivity of farmers. The poorest households engaged in subsistence agriculture bear a far heavier disease burden than their wealthier counterparts, experiencing an average yield loss due to schistosomiasis of between 32 and 45%. We show that the returns to water resources development are substantially reduced once its health effects are taken into account: villages in proximity of large-scale dams suffer an average yield loss of around 20%, and this burden decreases as distance between dams and villages increases. CONCLUSIONS This study provides a rigorous estimation of how schistosomiasis affects agricultural production and how it is both a driver and a consequence of poverty. It further quantifies the tradeoff between the economics of water infrastructures and their impact on public health. Although we focus on Burkina Faso, our approach can be applied to any country in which schistosomiasis is endemic.
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Affiliation(s)
- Daniele Rinaldo
- Department of Economics and Land, Environment, Economics and Policy Institute (LEEP), University of Exeter, Exeter, England.
| | - Javier Perez-Saez
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Penelope Vounatsou
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jean-Louis Arcand
- Department of International Economics, The Graduate Institute of International and Development Studies, Geneva, Switzerland.,Fondation pour les études et recherches sur le développement international (FERDI), Clermont-Ferrand, France
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22
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Pearson MS, Tedla BA, Mekonnen GG, Proietti C, Becker L, Nakajima R, Jasinskas A, Doolan DL, Amoah AS, Knopp S, Rollinson D, Ali SM, Kabole F, Hokke CH, Adegnika AA, Field MA, van Dam G, Corstjens PLAM, Mduluza T, Mutapi F, Oeuvray C, Greco B, Chaiyadet S, Laha T, Cai P, McManus DP, Bottazzi ME, Felgner PL, Sotillo J, Loukas A. Immunomics-guided discovery of serum and urine antibodies for diagnosing urogenital schistosomiasis: a biomarker identification study. THE LANCET MICROBE 2021; 2:e617-e626. [PMID: 34977830 PMCID: PMC8683377 DOI: 10.1016/s2666-5247(21)00150-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background Sensitive diagnostics are needed for effective management and surveillance of schistosomiasis so that current transmission interruption goals set by WHO can be achieved. We aimed to screen the Schistosoma haematobium secretome to find antibody biomarkers of schistosome infection, validate their diagnostic performance in samples from endemic populations, and evaluate their utility as point of care immunochromatographic tests (POC-ICTs) to diagnose urogenital schistosomiasis in the field. Methods We did a biomarker identification study, in which we constructed a proteome array containing 992 validated and predicted proteins from S haematobium and screened it with serum and urine antibodies from endemic populations in Gabon, Tanzania, and Zimbabwe. Arrayed antigens that were IgG-reactive and a select group of antigens from the worm extracellular vesicle proteome, predicted to be diagnostically informative, were then evaluated by ELISA using the same samples used to probe arrays, and samples from individuals residing in a low-endemicity setting (ie, Pemba and Unguja islands, Zanzibar, Tanzania). The two most sensitive and specific antigens were incorporated into POC-ICTs to assess their ability to diagnose S haematobium infection from serum in a field-deployable format. Findings From array probing, in individuals who were infected, 208 antigens were the targets of significantly elevated IgG responses in serum and 45 antigens were the targets of significantly elevated IgG responses in urine. Of the five proteins that were validated by ELISA, Sh-TSP-2 (area under the curve [AUC]serum=0·98 [95% CI 0·95–1·00]; AUCurine=0·96 [0·93–0·99]), and MS3_01370 (AUCserum=0·93 [0·89–0·97]; AUCurine=0·81 [0·72–0·89]) displayed the highest overall diagnostic performance in each biofluid and exceeded that of S haematobium-soluble egg antigen in urine (AUC=0·79 [0·69–0·90]). When incorporated into separate POC-ICTs, Sh-TSP-2 showed absolute specificity and a sensitivity of 75% and MS3_01370 showed absolute specificity and a sensitivity of 89%. Interpretation We identified numerous biomarkers of urogenital schistosomiasis that could form the basis of novel antibody diagnostics for this disease. Two of these antigens, Sh-TSP-2 and MS3_01370, could be used as sensitive, specific, and field-deployable diagnostics to support schistosomiasis control and elimination initiatives, with particular focus on post-elimination surveillance. Funding Australian Trade and Investment Commission and Merck Global Health Institute.
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Affiliation(s)
- Mark S Pearson
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Correspondence to: Dr Mark Pearson, Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia
| | - Bemnet A Tedla
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Gebeyaw G Mekonnen
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Carla Proietti
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Luke Becker
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Rie Nakajima
- University of California Irvine, Irvine, CA, USA
| | - Al Jasinskas
- University of California Irvine, Irvine, CA, USA
| | - Denise L Doolan
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Abena S Amoah
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, UK
- Department of Life Sciences, University of Basel, Basel, Switzerland
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, UK
| | - Said M Ali
- Public Health Laboratory, Ivo de Carneri, Pemba, Tanzania
| | - Fatma Kabole
- Neglected Diseases Programme, Ministry of Health, Unguja, Tanzania
| | - Cornelis H Hokke
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Akim A Adegnika
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany
- German Center for Infection Research, Tübingen, Germany
| | - Matt A Field
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Govert van Dam
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Paul L A M Corstjens
- Department of Molecular Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Takafira Mduluza
- Biochemistry Department, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe
- Tackling Infections to Benefit Africa Partnership, NIHR Global Health Research Unit, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe
| | - Francisca Mutapi
- Department of Molecular Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
- Tackling Infections to Benefit Africa Partnership, NIHR Global Health Research Unit, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Ashworth Laboratories, Edinburgh, UK
| | | | | | - Sujittra Chaiyadet
- Tropical Medicine Graduate Program, Academic Affairs, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Thewarach Laha
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Pengfei Cai
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Donald P McManus
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Maria Elena Bottazzi
- Texas Children's Hospital Center for Vaccine Development, Department of Pediatrics and National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | | | - Javier Sotillo
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Parasitology Reference and Research Laboratory, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Alex Loukas
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Prof Alex Loukas, Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia
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23
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Banda GT, Deribe K, Davey G. How can we better integrate the prevention, treatment, control and elimination of neglected tropical diseases with other health interventions? A systematic review. BMJ Glob Health 2021; 6:bmjgh-2021-006968. [PMID: 34663634 PMCID: PMC8524265 DOI: 10.1136/bmjgh-2021-006968] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 09/27/2021] [Indexed: 11/17/2022] Open
Abstract
Background Globally, about 1.7 billion people living in poverty are affected by one or more of a group of disabling, disfiguring and poverty-promoting conditions known as neglected tropical diseases (NTDs). Major global health actors, like the WHO, have endorsed a shift from vertical to integrated NTD management. Objective This systematic review aimed to evaluate how integration is being conducted and how we can improve it. Methods PubMed, Medline, Cochrane library, Web of Science, Trip, Embase, Global Health and Google Scholar were searched from 1 April to 22 July 2020. We included peer-reviewed articles published between 1 January 2000 and 22 July 2020 in English. Results Database searches produced 24 565 studies, of which 35 articles met the inclusion criteria. Twenty of these articles were conducted in sub-Saharan Africa. Twenty articles were also published between 2015 and 2020. Literature revealed that NTDs have been integrated—among themselves; with water, sanitation and hygiene programmes; with vector control; with primary healthcare; with immunisation programmes; and with malaria management. Integrated mass drug administration for multiple NTDs was the most common method of integration. The three complex, yet common characteristics of successful integration were good governance, adequate financing and total community engagement. Conclusion The dataset identified integrated management of NTDs to be cost effective and potentially to increase treatment coverage. However, the identified modes of integration are not exclusive and are limited by the available literature. Nonetheless, integration should urgently be implemented, while considering the programmatic and sociopolitical context. PROSPERO registration number The study protocol was registered with PROSPERO number, CRD42020167358.
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Affiliation(s)
- Gift Treighcy Banda
- Department of Global Health and Infection, Brighton and Sussex Medical School, Brighton, UK .,Mzimba District Hospital, Malawi Ministry of Health, Mzimba, Malawi
| | - Kebede Deribe
- Department of Global Health and Infection, Brighton and Sussex Medical School, Brighton, UK.,School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Gail Davey
- Department of Global Health and Infection, Brighton and Sussex Medical School, Brighton, UK.,School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
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24
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Novel tools and strategies for breaking schistosomiasis transmission: study protocol for an intervention study. BMC Infect Dis 2021; 21:1024. [PMID: 34592960 PMCID: PMC8482678 DOI: 10.1186/s12879-021-06620-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 08/26/2021] [Indexed: 12/12/2022] Open
Abstract
Background Global elimination of schistosomiasis as a public health problem is set as target in the new World Health Organization’s Neglected Tropical Diseases Roadmap for 2030. Due to a long history of interventions, the Zanzibar islands of Tanzania have reached this goal since 2017. However, challenges occur on the last mile towards interruption of transmission. Our study will investigate new tools and strategies for breaking schistosomiasis transmission. Methods The study is designed as an intervention study, documented through repeated cross-sectional surveys (2020–2024). The primary endpoint will be the sensitivity of a surveillance-response approach to detect and react to outbreaks of urogenital schistosomiasis over three years of implementation. The surveys and multi-disciplinary interventions will be implemented in 20 communities in the north of Pemba island. In low-prevalence areas, surveillance-response will consist of active, passive and reactive case detection, treatment of positive individuals, and focal snail control. In hotspot areas, mass drug administration, snail control and behaviour change interventions will be implemented. Parasitological cross-sectional surveys in 20 communities and their main primary schools will serve to adapt the intervention approach annually and to monitor the performance of the surveillance-response approach and impact of interventions. Schistosoma haematobium infections will be diagnosed using reagent strips and urine filtration microscopy, and by exploring novel point-of-care diagnostic tests. Discussion Our study will shed light on the field applicability and performance of novel adaptive intervention strategies, and standard and new diagnostic tools for schistosomiasis elimination. The evidence and experiences generated by micro-mapping of S. haematobium infections at community level, micro-targeting of new adaptive intervention approaches, and application of novel diagnostic tools can guide future strategic plans for schistosomiasis elimination in Zanzibar and inform other countries aiming for interruption of transmission. Trial registration ISRCTN, ISCRCTN91431493. Registered 11 February 2020, https://www.isrctn.com/ISRCTN91431493
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25
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Ouattara M, Bassa FK, Diakité NR, Hattendorf J, Coulibaly JT, Yao PK, Tian-Bi YNT, Konan CK, Assaré RK, Koné N, Guindo-Coulibaly N, Utzinger J, N'Goran EK. Effectiveness of Four Different Interventions against Schistosoma haematobium in a Seasonal Transmission Setting of Côte d'Ivoire: A Cluster Randomized Trial. Clin Infect Dis 2021; 74:2181-2190. [PMID: 34519344 PMCID: PMC9258925 DOI: 10.1093/cid/ciab787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Annual mass drug administration (MDA) using praziquantel is the cornerstone of schistosomiasis morbidity control, but is not sufficient to interrupt transmission. We implemented a cluster-randomized trial to compare the effectiveness of four different intervention packages to interrupt transmission of Schistosoma haematobium in a seasonal transmission setting of Côte d'Ivoire. METHODS Sixty-four localities with a S. haematobium prevalence in school children aged 13-14 years above 4% were randomly assigned to one of four intervention arms over a 3-year period: (1) the current standard strategy consisting of annual MDA before peak of transmission; (2) annual MDA after peak of transmission; (3) biannual MDA; and (4) standard MDA combined with snail control. The primary outcome was prevalence and intensity of S. haematobium infection in children aged 9-12 years 1 year after the final intervention, using urine filtration performed by experienced microscopists. RESULTS By study end, we observed the lowest S. haematobium prevalence in the biannual MDA, compared to the standard treatment arm (0.6% vs. 7.5%; odds ratio [OR] = 0.07, 95% confidence interval [CI] = 0.02 to 0.24). The prevalence in arms 2 and 4 was about 3.5%, which was not statistically significantly different from the standard strategy (both ORs 0.4, 95% CI = 0.1 to ~1.8). New cases of infection were still observed in all arms at study end. CONCLUSIONS Biannual MDA was the only regimen that outperformed the standard treatment. All strategies resulted in decreased prevalence of infection, however none of them was able to interrupt transmission of S. haematobium within a 3-year period.
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Affiliation(s)
- Mamadou Ouattara
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Fidèle K Bassa
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Nana R Diakité
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jean T Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire.,Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Patrick K Yao
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Yves-Nathan T Tian-Bi
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Cyrille K Konan
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Rufin K Assaré
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Naférima Koné
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Négnorogo Guindo-Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Eliézer K N'Goran
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
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Li HM, Qin ZQ, Bergquist R, Qian MB, Xia S, Lv S, Xiao N, Utzinger J, Zhou XN. Nucleic acid amplification techniques for the detection of Schistosoma mansoni infection in humans and the intermediate snail host: a structured review and meta-analysis of diagnostic accuracy. Int J Infect Dis 2021; 112:152-164. [PMID: 34474147 DOI: 10.1016/j.ijid.2021.08.061] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/18/2021] [Accepted: 08/25/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Schistosomiasis is a parasitic disease caused by hematodes of genus Schistosoma. This review evaluated the available nucleic acid amplification techniques for diagnosing S. mansoni infections in humans, intermediate host snails, and presumed rodent reservoirs. METHODS Sensitivity, specificity, diagnostic odds ratio (DOR), and 95% CI were calculated based on available literature. The potential of PCR, nPCR, PCR-ELISA, qPCR, and LAMP was compared for diagnosing S. mansoni infections. RESULTS A total of 546 published records were identified. Quality assessment by QUADAS-2 revealed an uncertain risk in most studies, and 21 references were included in the final. For human samples, the four nucleic acid amplification techniques showed an overall sensitivity of 89.79% (95% CI: 83.92%-93.67%), specificity of 87.70% (95% CI: 72.60%-95.05%), and DOR of 37.73 (95% CI: 21.79-65.33). LAMP showed the highest sensitivity, followed by PCR-ELISA, PCR, and qPCR, while this order was almost reversed for specificity; qPCR had the highest AUC. For rodent samples, qPCR showed modest sensitivity (68.75%, 95% CI: 43.32%-86.36%) and high specificity (92.45%, 95% CI: 19.94%-99.83%). For snail samples, PCR and nPCR assays showed high sensitivity of 90.06% (95% CI: 84.39%-93.82%) and specificity of 85.51% (95% CI: 54.39%-96.69%). CONCLUSION Nucleic acid amplification techniques had high diagnostic potential for identifying S. mansoni infections in humans.
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Affiliation(s)
- Hong-Mei Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China
| | - Zhi-Qiang Qin
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China
| | | | - Men-Bao Qian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China; School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Shang Xia
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China; Ingerod, Brastad, Sweden (formerly with the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases, World Health Organization, Geneva, Switzerland)
| | - Shan Lv
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China; School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Ning Xiao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China; School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Jurg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, People's Republic of China; NHC Key Laboratory of Parasite and Vector Biology, Shanghai, People's Republic of China; WHO Collaborating Centre for Tropical Diseases, Shanghai, People's Republic of China; National Center for International Research on Tropical Diseases, Shanghai, People's Republic of China; School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
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Person B, Rollinson D, Ali SM, Mohammed UA, A'kadir FM, Kabole F, Knopp S. Evaluation of a urogenital schistosomiasis behavioural intervention among students from rural schools in Unguja and Pemba islands, Zanzibar. Acta Trop 2021; 220:105960. [PMID: 34004172 PMCID: PMC8223490 DOI: 10.1016/j.actatropica.2021.105960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/31/2021] [Accepted: 05/08/2021] [Indexed: 12/02/2022]
Abstract
Children self-reported changes in urogenital schistosomiasis risk taking behaviours. Children self-reported an increase in swallowing anthelmintic drugs during MDA. Rebranding the concept of “worm” to “blood fluke” created a critical perceived health threat. The Health Belief Model was a viable foundation for the behavioural intervention.
Urogenital schistosomiasis is a common experience among children in Zanzibar. There is a paucity of behavioural science-based, health education and behaviour change (HEBC) interventions for school-aged children, those at greatest risk for urogenital schistosomiasis. We assessed the influence of a HEBC intervention, guided by the Health Belief model, among rural schoolchildren on Pemba and Unguja islands in Zanzibar, Tanzania. From 2012 to 2016, a cluster-randomized trial to assess three different interventions against urogenital schistosomiasis was conducted in 90 schools and shehias across Zanzibar. The HEBC intervention was implemented in 15 schools per island. In 2017, at the trial conclusion, we administered written questionnaires to schoolchildren from 4 HEBC intervention schools and 4 not HEBC exposed schools on each island, respectively. Responses were compared between students that were exposed or not exposed to the HEBC intervention using a Fisher's exact test. A total of 1451 students, 708 from intervention and 743 from non-intervention schools completed the questionnaire. Noting some between island differences, students who had received the HEBC interventions reported significant improvements in knowledge about Schistosoma haematobium transmission and personal risk, strategies for schistosomiasis prevention, and self-reported changes in risk behaviours: stopped washing laundry/dishes 49.4% (350/708) versus 5.8% (43/743), stopped bathing in streams/ponds 49.4% (350/708) versus 4.2% (31/743), and stopped playing in streams/ponds 40.8% (289/708) versus 10.8% (80/743). HEBC exposed children also reported a significant increase in swallowing tablets during mass drug administration (MDA) campaigns (when they had not before) 30.2% (214/708) versus 4.6% (34/743). The school based HEBC interventions were associated with desirable positive behaviour change among students. Data suggest that scaling up HEBC interventions to all schools in high-risk areas, augmented with bi-annual MDA, can help to reduce prevalence of urogenital schistosomiasis in Zanzibar, strengthening the possibility for future disease elimination.
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Affiliation(s)
- Bobbie Person
- Consultant of the Schistosomiasis Consortium for Operational Research and Evaluation, University of Georgia, Atlanta, Georgia, USA
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom
| | - Said M Ali
- Public Health Laboratory - Ivo de Carneri, P. O. Box 122, Chake Chake, Pemba, United Republic of Tanzania
| | - Ulfat A Mohammed
- Public Health Laboratory - Ivo de Carneri, P. O. Box 122, Chake Chake, Pemba, United Republic of Tanzania
| | - Faiza M A'kadir
- Neglected Diseases Program, Ministry of Health, P.O. Box 236, Zanzibar Town, Unguja, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Diseases Program, Ministry of Health, P.O. Box 236, Zanzibar Town, Unguja, United Republic of Tanzania
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland; University of Basel, Petersplatz 1, 4003 Basel, Switzerland.
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Revisiting density-dependent fecundity in schistosomes using sibship reconstruction. PLoS Negl Trop Dis 2021; 15:e0009396. [PMID: 33983965 PMCID: PMC8148369 DOI: 10.1371/journal.pntd.0009396] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 05/25/2021] [Accepted: 04/19/2021] [Indexed: 11/19/2022] Open
Abstract
The stability of parasite populations is regulated by density-dependent processes occurring at different stages of their life cycle. In dioecious helminth infections, density-dependent fecundity is one such regulatory process that describes the reduction in egg production by female worms in high worm burden within-host environments. In human schistosomiasis, the operation of density-dependent fecundity is equivocal and investigation is hampered by the inaccessibility of adult worms that are located intravascularly. Current understanding is almost exclusively limited to data collected from two human autopsy studies conducted over 40 years ago, with subsequent analyses having reached conflicting conclusions. Whether egg production is regulated in a density-dependent manner is key to predicting the effectiveness of interventions targeting the elimination of schistosomiasis and to the interpretation of parasitological data collected during monitoring and evaluation activities. Here, we revisit density-dependent fecundity in the two most globally important human Schistosoma spp. using a statistical modelling approach that combines molecular inference on the number of parents/adult worms in individual human hosts with parasitological egg count data from mainland Tanzania and Zanzibar. We find a non-proportional relationship between S. haematobium egg counts and inferred numbers of female worms, providing the first clear evidence of density-dependent fecundity in this schistosome species. We do not find robust evidence for density-dependent fecundity in S. mansoni because of high sensitivity to some modelling assumptions and the lower statistical power of the available data. We discuss the strengths and limitations of our model-based analytical approach and its potential for improving our understanding of density dependence in schistosomiasis and other human helminthiases earmarked for elimination. Schistosomiasis is a devastating disease of poverty currently estimated to infect over 220 million people. It is caused by parasitic worms (blood flukes) that live for, on average, 5–7 years inside the blood vessels of infected hosts and produce hundreds of eggs daily. Whether egg production is regulated in a density-dependent manner, and if so under what conditions, has been controversial for schistosomiasis, and investigation is hampered due to the inaccessible location of adult worms. Resolving this fundamental question is important because density dependencies determine the resilience of helminthiases to interventions. Here, we have revisited this longstanding and unresolved question of density-dependent fecundity in human schistosomes using a novel statistical modelling approach that combines information from molecular and parasitological data. We report the first clear evidence of density-dependent fecundity in S. haematobium, the causative agent of millions of cases of urogenital schistosomiasis. Our findings are of critical importance both to mathematical modellers predicting the impact of interventions and to public health policy makers striving to meet the 2030 elimination targets for schistosomiasis. This study also serves to illustrate a new biostatistical approach that could be applied to investigate density dependencies in other helminthiases where adult parasites are inaccessible.
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Kura K, Ayabina D, Toor J, Hollingsworth TD, Anderson RM. Disruptions to schistosomiasis programmes due to COVID-19: an analysis of potential impact and mitigation strategies. Trans R Soc Trop Med Hyg 2021; 115:236-244. [PMID: 33515038 PMCID: PMC7928593 DOI: 10.1093/trstmh/traa202] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/28/2020] [Accepted: 01/03/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The 2030 goal for schistosomiasis is elimination as a public health problem (EPHP), with mass drug administration (MDA) of praziquantel to school-age children (SAC) as a central pillar of the strategy. However, due to coronavirus disease 2019, many mass treatment campaigns for schistosomiasis have been halted, with uncertain implications for the programmes. METHODS We use mathematical modelling to explore how postponement of MDA and various mitigation strategies affect achievement of the EPHP goal for Schistosoma mansoni and S. haematobium. RESULTS For both S. mansoni and S. haematobium in moderate- and some high-prevalence settings, the disruption may delay the goal by up to 2 y. In some high-prevalence settings, EPHP is not achievable with current strategies and so the disruption will not impact this. Here, increasing SAC coverage and treating adults can achieve the goal. The impact of MDA disruption and the appropriate mitigation strategy varies according to the baseline prevalence prior to treatment, the burden of infection in adults and the stage of the programme. CONCLUSIONS Schistosomiasis MDA programmes in medium- and high-prevalence areas should restart as soon as is feasible and mitigation strategies may be required in some settings.
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Affiliation(s)
- Klodeta Kura
- London Centre for Neglected Tropical Disease Research, London, UK.,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary's Campus, Imperial College London, London, UK.,MRC Centre for Global Infectious Disease Analysis
| | - Diepreye Ayabina
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford OX3 7LF, UK
| | - Jaspreet Toor
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford OX3 7LF, UK
| | - T Deirdre Hollingsworth
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford OX3 7LF, UK
| | - Roy M Anderson
- London Centre for Neglected Tropical Disease Research, London, UK.,Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary's Campus, Imperial College London, London, UK.,MRC Centre for Global Infectious Disease Analysis.,DeWorm3 Project, Natural History Museum of London, London, UK
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30
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Wanderley FSO, Montarroyos U, Bonfim C, Cunha-Correia C. Effectiveness of mass treatment of Schistosoma mansoni infection in socially vulnerable areas of a state in northeastern Brazil, 2011-2014. ACTA ACUST UNITED AC 2021; 79:30. [PMID: 33750474 PMCID: PMC7941929 DOI: 10.1186/s13690-021-00549-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/21/2021] [Indexed: 11/21/2022]
Abstract
Background To assess the effectiveness of mass treatment of Schistosoma mansoni infection in socially vulnerable endemic areas in northeastern Brazil. Method An ecological study was conducted, in which 118 localities in 30 municipalities in the state of Pernambuco were screened before 2011 and in 2014 (after mass treatment). Information on the endemic baseline index, mass treatment coverage, socio-environmental conditions and social vulnerability index were used in the multiple correspondence analysis. One hundred fourteen thousand nine hundred eighty-seven people in 118 locations were examined. Results The first two dimensions of the multiple correspondence analysis represented 55.3% of the variability between locations. The human capital component of the social vulnerability index showed an association with the baseline endemicity index. There was a significant reduction in positivity for schistosomes. For two rounds, for every extra 1% of initial endemicity index, the fixed effect of 13.62% increased by 0.0003%, achieving at most 15.94%. Conclusions The mass treatment intervention helped to reduce transmission of schistosomiasis in areas of high endemicity. Thus, it can be recommended that application of mass treatment should be accompanied by other control actions, such as basic sanitation, monitoring of intermediate vectors and case surveillance. Supplementary Information The online version contains supplementary material available at 10.1186/s13690-021-00549-9.
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Affiliation(s)
- Flávia Silvestre Outtes Wanderley
- Department of Neurology, Faculdade de Ciências Médicas, Postgraduate Course on Health Sciences, University of Pernambuco, Rua Arnóbio Marques, 310, Santo Amaro, Recife, Pernambuco, CEP 50100-130, Brazil
| | - Ulisses Montarroyos
- Department of Neurology, Faculdade de Ciências Médicas, Postgraduate Course on Health Sciences, University of Pernambuco, Rua Arnóbio Marques, 310, Santo Amaro, Recife, Pernambuco, CEP 50100-130, Brazil
| | - Cristine Bonfim
- Social Research Department, Joaquim Nabuco Foundation, Recife, PE, Brazil
| | - Carolina Cunha-Correia
- Department of Neurology, Faculdade de Ciências Médicas, Postgraduate Course on Health Sciences, University of Pernambuco, Rua Arnóbio Marques, 310, Santo Amaro, Recife, Pernambuco, CEP 50100-130, Brazil.
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Toor J, Rollinson D, Turner HC, Gouvras A, King CH, Medley GF, Hollingsworth TD, Anderson RM. Achieving Elimination as a Public Health Problem for Schistosoma mansoni and S. haematobium: When Is Community-Wide Treatment Required? J Infect Dis 2021; 221:S525-S530. [PMID: 31829414 PMCID: PMC7289541 DOI: 10.1093/infdis/jiz609] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The World Health Organization (WHO) has set elimination as a public health problem (EPHP) as a goal for schistosomiasis. As the WHO treatment guidelines for schistosomiasis are currently under revision, we investigate whether school-based or community-wide treatment strategies are required for achieving the EPHP goal. In low- to moderate-transmission settings with good school enrolment, we find that school-based treatment is sufficient for achieving EPHP. However, community-wide treatment is projected to be necessary in certain high-transmission settings as well as settings with low school enrolment. Hence, the optimal treatment strategy depends on setting-specific factors such as the species present, prevalence prior to treatment, and the age profile of infection.
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Affiliation(s)
- Jaspreet Toor
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
| | - David Rollinson
- Department of Life Sciences, Natural History Museum, London, UK.,Global Schistosomiasis Alliance, Department of Life Sciences, Natural History Museum, London, UK
| | - Hugo C Turner
- Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Anouk Gouvras
- Global Schistosomiasis Alliance, Department of Life Sciences, Natural History Museum, London, UK
| | - Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, USA
| | - Graham F Medley
- Centre for Mathematical Modelling of Infectious Disease, London School of Hygiene and Tropical Medicine, London, UK
| | - T Déirdre Hollingsworth
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
| | - Roy M Anderson
- London Centre for Neglected Tropical Disease Research, Department of Infectious Disease Epidemiology, Imperial College London, London, UK.,Medical Research Council Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK.,The DeWorm3 Project, Natural History Museum, London, UK
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Impact of seven years of mass drug administration and recrudescence of Schistosoma haematobium infections after one year of treatment gap in Zanzibar: Repeated cross-sectional studies. PLoS Negl Trop Dis 2021; 15:e0009127. [PMID: 33577601 PMCID: PMC7880478 DOI: 10.1371/journal.pntd.0009127] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 01/12/2021] [Indexed: 11/25/2022] Open
Abstract
Background Considerable progress towards the elimination of urogenital schistosomiasis was made by the Zanzibar Elimination of Schistosomiasis Transmission project from 2012 till 2016, when biannual praziquantel mass drug administration (MDA) alone or with additional snail control or behaviour change interventions were implemented. Annual MDA was continued in 2017 and 2018, but not in 2019, imposing a 16-month treatment gap. We monitored the Schistosoma haematobium prevalence from 2012 till 2020 and assessed recrudescence patterns with focus on 2020. Methodology Repeated cross-sectional surveys were conducted from 2011/12 till 2020 in 90 communities and 90 schools in Zanzibar. Annually, around 4,500 adults and up to 20,000 schoolchildren were surveyed. The S. haematobium prevalence was detected by urine filtration and reagent strips. In 2020, risk factors for infection were investigated using generalized estimated equation models. Principal findings In adults, the apparent S. haematobium prevalence was 3.9% in 2011 and 0.4% in 2020. In schoolchildren, the prevalence decreased from 6.6% in 2012 to 1.2% in 2019 with vicissitudes over the years. Prominent recrudescence of infection from 2.8% in 2019 to 9.1% (+225%) in 2020 was observed in 29 schools with historically moderate prevalences (≥10%). Compared with 2019, reinfection in 2020 was particularly striking in boys aged 9–16 years. Being male was a risk factor for infection in 2020 (adults: odds ratio (OR): 6.24, 95% confidence interval (95% CI): 1.96–19.60; schoolchildren: OR: 2.06, 95% CI: 1.52–2.78). Living near to a natural freshwater body significantly increased the odds of infection in adults (OR: 2.90, CI: 1.12–7.54). Conclusions/Significance After 11 rounds of MDA over 7 years and a 16-month treatment gap, the urogenital schistosomiasis prevalence considerably rebounded in hotspot areas. Future elimination efforts in Zanzibar should focus on re-intensifying MDA plus additional interventions in hotspot areas. In low-prevalence areas, the strategy might be adapted from MDA to targeted surveillance-response. Schistosomiasis is a neglected tropical disease caused by parasitic blood flukes of the genus Schistosoma. On the Zanzibar islands, United Republic of Tanzania, interventions to eliminate urogenital schistosomiasis commenced in 2012. From 2012 to 2016, the population was treated biannually with praziquantel and, additionally, some areas received mollusciciding against the intermediate host snail, or educational measures for behavior change. Mass drug administration (MDA) with praziquantel was continued annually in 2017 and 2018, but not in 2019. As a result of the interventions, the overall S. haematobium prevalence was reduced to 0.4% in adults and 3.4% in schoolchildren in 2020. However, in some areas, the MDA gap in 2019 resulted in a considerable rebound of infections. The recrudescence in 2020 was particularly striking for boys aged 9–16 years. In general, in 2020, male participants had higher odds of infection than females. Adults living near to a natural freshwater body also showed an increased risk of S. haematobium infection. Future elimination efforts in Zanzibar should focus on re-intensifying elimination interventions, including MDA, snail control and behavior change in hotspot areas. In low-prevalence areas, the strategy might be adapted from MDA to targeted interventions, such as surveillance-response.
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Ouattara M, Diakité NR, Yao PK, Saric J, Coulibaly JT, Assaré RK, Bassa FK, Koné N, Guindo-Coulibaly N, Hattendorf J, Utzinger J, N’Goran EK. Effectiveness of school-based preventive chemotherapy strategies for sustaining the control of schistosomiasis in Côte d'Ivoire: Results of a 5-year cluster randomized trial. PLoS Negl Trop Dis 2021; 15:e0008845. [PMID: 33449924 PMCID: PMC7810315 DOI: 10.1371/journal.pntd.0008845] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 09/30/2020] [Indexed: 11/18/2022] Open
Abstract
Background Preventive chemotherapy using praziquantel is the mainstay for schistosomiasis control. However, there is little evidence on what is supposed to be the most effective school-based treatment strategy to sustain morbidity control. The aim of this study was to compare differences in Schistosoma mansoni prevalence and infection intensity between three different schedules of school-based preventive chemotherapy in an area with moderate prevalence of S. mansoni in Côte d’Ivoire. Methodology Seventy-five schools were randomly assigned to one of three intervention arms: (i) annual school-based preventive chemotherapy with praziquantel (40 mg/kg) over four years; (ii) praziquantel treatment only in the first two years, followed by two years whithout treatment; and (iii) praziquantel treatment in years 1 and 3 without treatment in-between. Cross-sectional parasitologic surveys were carried out prior to each round of preventive chemotherapy. The difference in S. mansoni prevalence and infection intensity was assessed by multiple Kato-Katz thick smears, among children aged 9–12 years at the time of each survey. First-grade children, aged 5–8 years who had never received praziquantel, were also tested at baseline and at the end of the study. Principal findings Overall, 7,410 children aged 9–12 years were examined at baseline and 7,223 at the final survey. The baseline prevalence of S. mansoni was 17.4%, 20.2%, and 25.2% in arms 1, 2, and 3, respectively. In the final year, we observed the lowest prevalence of 10.4% in arm 1, compared to 18.2% in arm 2 and 17.5% in arm 3. The comparison between arms 1 and 2 estimated an odds ratio (OR) of 0.52 but the difference was not statistically significant (95% confidence interval (CI) = 0.23–1.16). Likewise the difference between arms 1 and 3 lacked statistical significance (OR = 0.55, 95% CI = 0.23–1.29). There was no noteworthy difference observed between arms 2 and 3 (OR = 1.06, 95% CI = 0.64–1.75). The lowest S. mansoni fecal egg counts in the final year survey were observed in arm 1 (7.9 eggs per gram of stool (EPG)). However, compared with 11.5 EPG in arm 2 and 15.4 EPG in arm 3, the difference lacked statistical significance. There were 4,812 first-grade children examined at baseline and 4,513 in the final survey. The overall prevalence of S. mansoni in these children slightly decreased in arms 1 (from 4.5% to 3.6%) and 2 (from 4.7% to 4.3%), but increased in arm 3 (from 6.8% to 7.9%). However, there was no significant difference in prevalence and infection intensity observed between study arms. Conclusions/significance The three treatment schedules investigated led to a reduction in the prevalence and intensity of S. mansoni infection among children aged 9–12 years. Comparing intervention arms at the end of the study, no statistically significant differences were observed between annual treatement and the other two treatment schedules, neither in reduction of prevalence nor intensity of infection. It is important to combine our results with those of three sister trials conducted simultaneously in other African countries, before final recommendations can be drawn. The World Health Organization (WHO) recommends preventive chemotherapy with praziquantel as the global strategy for morbidity control of schistosomiasis. The guidelines include target groups and treatment frequencies based on prevalence in school-age children. However, these recommendations are based on expert opinion. The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) put forward a series of cluster-randomized trials in different African countries, including Côte d’Ivoire, to identify the most suitable approach to gain and sustain the control of schistosomiasis. Results from Côte d’Ivoire did not show statistically significant differences between three school-based treatment schedules (i.e., annual treatment over four years; treatment only in the first two years, followed by two years whithout treatment; and treatment every other year without treatment in-between) in reducing prevalence and intensity of Schistosoma mansoni infection among children aged 9–12 years. The results in first-grade children with an age of 5–8 years entering school who had never received deworming drugs showed no significant difference in the prevalence and intensity of S. mansoni infection between the different treatments at the study end, suggesting that the three strategies were not significantly different for reducing the disease transmission in affected communities. However, our data should be combined with other SCORE studies carried out elsewhere in Africa. A meta-analysis including the results of the sister trials could help to conclude and make more generic recommendations.
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Affiliation(s)
- Mamadou Ouattara
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- * E-mail:
| | - Nana R. Diakité
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Patrick K. Yao
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Jasmina Saric
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jean T. Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Rufin K. Assaré
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Fidèle K. Bassa
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Naférima Koné
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Négnorogo Guindo-Coulibaly
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Eliézer K. N’Goran
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
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34
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King CH, Bertsch D, Andrade GN, Burnim M, Ezeamama AE, Binder S, Colley DG. The Schistosomiasis Consortium for Operational Research and Evaluation Rapid Answers Project: Systematic Reviews and Meta-Analysis to Provide Policy Recommendations Based on Available Evidence. Am J Trop Med Hyg 2020; 103:92-96. [PMID: 32400346 PMCID: PMC7351305 DOI: 10.4269/ajtmh.19-0806] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in late 2008 to conduct operational research to inform global health practices related to the control and elimination of schistosomiasis. The greatest part of the SCORE investment has been in multiyear, long-term efforts, including cluster-randomized trials of gaining and sustaining control of schistosomiasis, trials on elimination of schistosomiasis, and diagnostic test development and evaluation. In the course of planning and conducting SCORE studies, critical questions were raised that could be answered relatively quickly by collecting, collating, and synthesizing existing data. Through its Rapid Answers Project (RAP), the SCORE conducted seven systematic reviews, including four associated meta-analyses, on issues related to screening for schistosomiasis, enhancing mass drug administration, treatment impacts, and the efficacy of snail control for prevention of human schistosomiasis. This article summarizes the findings of the seven RAP reports and provides links to the studies and their supporting information.
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Affiliation(s)
- Charles H King
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - David Bertsch
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Gisele N Andrade
- Escola de Enfermagem, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Michael Burnim
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Amara E Ezeamama
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, Georgia.,Department of Psychiatry, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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35
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Campbell CH, Binder S, King CH, Knopp S, Rollinson D, Person B, Webster B, Allan F, Utzinger J, Ame SM, Ali SM, Kabole F, N'Goran EK, Tediosi F, Salari P, Ouattara M, Diakité NR, Hattendorf J, S Andros T, Kittur N, Colley DG. SCORE Operational Research on Moving toward Interruption of Schistosomiasis Transmission. Am J Trop Med Hyg 2020; 103:58-65. [PMID: 32400354 PMCID: PMC7351301 DOI: 10.4269/ajtmh.19-0825] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
As part of its diverse portfolio, the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) included two cluster-randomized trials evaluating interventions that could potentially lead to interruption of schistosomiasis transmission (elimination) in areas of Africa with low prevalence and intensity of infection. These studies, conducted in Zanzibar and Côte d’Ivoire, demonstrated that multiyear mass drug administration (MDA) with praziquantel failed to interrupt the transmission of urogenital schistosomiasis, even when provided biannually and/or supplemented by small-scale implementation of additional interventions. Other SCORE activities related to elimination included a feasibility and acceptability assessment of test–treat–track–test–treat (T5) strategies and mathematical modeling. Future evaluations of interventions to eliminate schistosomiasis should recognize the difficulties inherent in conducting randomized controlled trials on elimination and in measuring small changes where baseline prevalence is low. Highly sensitive and specific diagnostic tests for use in very low–prevalence areas for schistosomiasis are not routinely available, which complicates accurate measurement of infection rates and assessment of changes resulting from interventions in these settings. Although not encountered in these two studies, as prevalence and intensity decrease, political and community commitment to population-wide MDA may decrease. Because of this potential problem, SCORE developed and funded the T5 strategy implemented in Egypt, Kenya, and Tanzania. It is likely that focal MDA campaigns, along with more targeted approaches, including a T5 strategy and snail control, will need to be supplemented with the provision of clean water and sanitation and behavior change communications to achieve interruption of schistosome transmission.
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Affiliation(s)
- Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Stefanie Knopp
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, London, United Kingdom.,University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - David Rollinson
- London Centre for Neglected Tropical Disease Research, Imperial College Faculty of Medicine, London, United Kingdom.,Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, London, United Kingdom
| | - Bobbie Person
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Bonnie Webster
- London Centre for Neglected Tropical Disease Research, Imperial College Faculty of Medicine, London, United Kingdom.,Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, London, United Kingdom
| | - Fiona Allan
- London Centre for Neglected Tropical Disease Research, Imperial College Faculty of Medicine, London, United Kingdom.,Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, London, United Kingdom
| | - Jürg Utzinger
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Shaali M Ame
- Public Health Laboratory - Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Said M Ali
- Public Health Laboratory - Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Tropical Diseases Unit, Ministry of Health Zanzibar, Unguja, United Republic of Tanzania
| | - Eliézer K N'Goran
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Fabrizio Tediosi
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Paola Salari
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Mamadou Ouattara
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Nana R Diakité
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire.,Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan, Côte d'Ivoire
| | - Jan Hattendorf
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Tamara S Andros
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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36
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Corstjens PLAM, de Dood CJ, Knopp S, Clements MN, Ortu G, Umulisa I, Ruberanziza E, Wittmann U, Kariuki T, LoVerde P, Secor WE, Atkins L, Kinung'hi S, Binder S, Campbell CH, Colley DG, van Dam GJ. Circulating Anodic Antigen (CAA): A Highly Sensitive Diagnostic Biomarker to Detect Active Schistosoma Infections-Improvement and Use during SCORE. Am J Trop Med Hyg 2020; 103:50-57. [PMID: 32400344 PMCID: PMC7351307 DOI: 10.4269/ajtmh.19-0819] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was funded in 2008 to conduct research that would support country schistosomiasis control programs. As schistosomiasis prevalence decreases in many places and elimination is increasingly within reach, a sensitive and specific test to detect infection with Schistosoma mansoni and Schistosoma haematobium has become a pressing need. After obtaining broad input, SCORE supported Leiden University Medical Center (LUMC) to modify the serum-based antigen assay for use with urine, simplify the assay, and improve its sensitivity. The urine assay eventually contributed to several of the larger SCORE studies. For example, in Zanzibar, we demonstrated that urine filtration, the standard parasite egg detection diagnostic test for S. haematobium, greatly underestimated prevalence in low-prevalence settings. In Burundi and Rwanda, the circulating anodic antigen (CAA) assay provided critical information about the limitations of the stool-based Kato–Katz parasite egg-detection assay for S. mansoni in low-prevalence settings. Other SCORE-supported CAA work demonstrated that frozen, banked urine specimens yielded similar results to fresh ones; pooling of specimens may be a useful, cost-effective approach for surveillance in some settings; and the assay can be performed in local laboratories equipped with adequate centrifuge capacity. These improvements in the assay continue to be of use to researchers around the world. However, additional work will be needed if widespread dissemination of the CAA assay is to occur, for example, by building capacity in places besides LUMC and commercialization of the assay. Here, we review the evolution of the CAA assay format during the SCORE period with emphasis on urine-based applications.
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Affiliation(s)
- Paul L A M Corstjens
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Claudia J de Dood
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, Netherlands
| | - Stefanie Knopp
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Michelle N Clements
- MRC Clinical Trials Unit, University College London, London, United Kingdom.,SCI Foundation, London, United Kingdom
| | | | - Irenee Umulisa
- African Leaders Malaria Alliance, Dar-es-Salam, Tanzania.,Malaria and Other Parasitic Diseases Division, Neglected Tropical Diseases and Other Parasitic Diseases Unit, Rwanda Biomedical Center, Ministry of Health, Kigali, Rwanda
| | - Eugene Ruberanziza
- Malaria and Other Parasitic Diseases Division, Neglected Tropical Diseases and Other Parasitic Diseases Unit, Rwanda Biomedical Center, Ministry of Health, Kigali, Rwanda
| | - Udo Wittmann
- Consult AG Statistical Services, Zurich, Switzerland.,SCI Foundation, London, United Kingdom
| | - Thomas Kariuki
- African Academy of Sciences, Alliance for Accelerating Excellence in Science in Africa, Nairobi, Kenya.,Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya
| | - Philip LoVerde
- Department of Biochemistry and Structural Biology, University of Texas Health, San Antonio, Texas
| | - William Evan Secor
- Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Lydia Atkins
- Ministry of Health and Wellness, Castries, St. Lucia
| | - Safari Kinung'hi
- Mwanza Research Centre, National Institute for Medical Research, Mwanza, Tanzania
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Govert J van Dam
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
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37
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Kittur N, Campbell CH, Binder S, Shen Y, Wiegand RE, Mwanga JR, Kinung'hi SM, Musuva RM, Odiere MR, Matendechero SH, Knopp S, Colley DG. Discovering, Defining, and Summarizing Persistent Hotspots in SCORE Studies. Am J Trop Med Hyg 2020; 103:24-29. [PMID: 32400365 PMCID: PMC7351310 DOI: 10.4269/ajtmh.19-0815] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) conducted large field studies on schistosomiasis control and elimination in Africa. All of these studies, carried out in low-, moderate-, and high-prevalence areas, resulted in a reduction in prevalence and intensity of Schistosoma infection after repeated mass drug administration (MDA). However, in all studies, there were locations that experienced minimal or no decline or even increased in prevalence and/or intensity. These areas are termed persistent hotspots (PHS). In SCORE studies in medium- to high-prevalence areas, at least 30% of study villages were PHS. There was no consistent relationship between PHS and the type or frequency of intervention, adequacy of reported MDA coverage, and prevalence or intensity of infection at baseline. In a series of small studies, factors that differed between PHS and villages that responded to repeated MDA as expected included sources of water for personal use, sanitation, and hygiene. SCORE studies comparing PHS with villages that responded to MDA suggest the potential for PHS to be identified after a few years of MDA. However, additional studies in different social-ecological settings are needed to develop generalizable approaches that program managers can use to identify and address PHS. This is essential if goals for schistosomiasis control and elimination are to be achieved.
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Affiliation(s)
- Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Ye Shen
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, Georgia
| | - Ryan E Wiegand
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland.,Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Joseph R Mwanga
- Department of Epidemiology, Biostatistics and Behavioral Sciences, School of Public Health, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Safari M Kinung'hi
- Mwanza Research Centre, National Institute of Medical Research, Mwanza, Tanzania
| | - Rosemary M Musuva
- Neglected Tropical Diseases Unit, Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Maurice R Odiere
- Neglected Tropical Diseases Unit, Center for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Sultani H Matendechero
- Division of Vector Borne and Neglected Tropical Diseases, Ministry of Health, Nairobi, Kenya
| | - Stefanie Knopp
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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38
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Colley DG, Jacobson JA, Binder S. Schistosomiasis Consortium for Operational Research and Evaluation (SCORE): Its Foundations, Development, and Evolution. Am J Trop Med Hyg 2020; 103:5-13. [PMID: 32400343 PMCID: PMC7351300 DOI: 10.4269/ajtmh.19-0785] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in late 2008 to conduct operational research that would inform practices related to the control and elimination of schistosomiasis. This article traces SCORE’s beginnings and underpinnings. These include an emphasis on openness and contributing to the development of a cohesive schistosomiasis control community, building linkages between researchers and national programs, and focusing on answering questions that will help Neglected Tropical Disease program managers to better control and eliminate schistosomiasis. It describes the development and implementation of SCORE’s multiple projects. SCORE began by drawing on advice from a broad range of experts by holding wide-ranging meetings that informed the priorities and protocols for SCORE research. SCORE’s major efforts included large, multicountry field studies comparing multiple strategies for mass drug administration with praziquantel, assessment of approaches to elimination, evaluation of a point-of-care assay for field mapping Schistosoma mansoni, and increasing the sensitivity of a laboratory-based diagnostic. SCORE also supported studies on morbidity due to schistosomiasis, quantification of vector snails and the detection of schistosome infections in snails, and changes in schistosome population genetics under praziquantel drug pressure. SCORE data and specimens are archived and will remain available for future research. Although much remains to be carried out, our hope is that through the already published articles and SCORE results described in this supplement, we will have provided a body of evidence to assist policy makers in the development of judicious guidelines for the control and elimination of schistosomiasis.
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Affiliation(s)
- Daniel G Colley
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Department of Microbiology, University of Georgia, Athens, Georgia
| | | | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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39
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Webster JP, Neves MI, Webster BL, Pennance T, Rabone M, Gouvras AN, Allan F, Walker M, Rollinson D. Parasite Population Genetic Contributions to the Schistosomiasis Consortium for Operational Research and Evaluation within Sub-Saharan Africa. Am J Trop Med Hyg 2020; 103:80-91. [PMID: 32400355 PMCID: PMC7351308 DOI: 10.4269/ajtmh.19-0827] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Analyses of the population genetic structure of schistosomes under the "Schistosomiasis Consortium for Operational Research and Evaluation" (SCORE) contrasting treatment pressure scenarios in Tanzania, Niger, and Zanzibar were performed to provide supplementary critical information with which to evaluate the impact of these large-scale control activities and guide how activities could be adjusted. We predicted that population genetic analyses would reveal information on a range of important parameters including, but not exclusive to, recruitment and transmission of genotypes, occurrence of hybridization events, differences in reproductive mode, and degrees of inbreeding, and hence, the evolutionary potential, and responses of parasite populations under contrasting treatment pressures. Key findings revealed that naturally high levels of gene flow and mixing of the parasite populations between neighboring sites were likely to dilute any effects imposed by the SCORE treatment arms. Furthermore, significant inherent differences in parasite fecundity were observed, independent of current treatment arm, but potentially of major impact in terms of maintaining high levels of ongoing transmission in persistent "biological hotspot" sites. Within Niger, naturally occurring Schistosoma haematobium/Schistosoma bovis viable hybrids were found to be abundant, often occurring in significantly higher proportions than that of single-species S. haematobium infections. By examining parasite population genetic structures across hosts, treatment regimens, and the spatial landscape, our results to date illustrate key transmission processes over and above that which could be achieved through standard parasitological monitoring of prevalence and intensity alone, as well as adding to our understanding of Schistosoma spp. life history strategies in general.
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Affiliation(s)
- Joanne P Webster
- London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom.,Department of Pathobiology and Population Sciences, Centre for Emerging, Endemic and Exotic Diseases (CEEED), Royal Veterinary College, University of London, Hawkshead Campus, Herts, United Kingdom
| | - Maria Inês Neves
- London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom.,Department of Pathobiology and Population Sciences, Centre for Emerging, Endemic and Exotic Diseases (CEEED), Royal Veterinary College, University of London, Hawkshead Campus, Herts, United Kingdom
| | - Bonnie L Webster
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, The Natural History Museum, London, United Kingdom.,London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom
| | - Tom Pennance
- School of Biosciences, Cardiff University, Cardiff, United Kingdom.,Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, The Natural History Museum, London, United Kingdom.,London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom
| | - Muriel Rabone
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, The Natural History Museum, London, United Kingdom.,London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom
| | - Anouk N Gouvras
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, The Natural History Museum, London, United Kingdom.,London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom
| | - Fiona Allan
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, The Natural History Museum, London, United Kingdom.,London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom
| | - Martin Walker
- London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom.,Department of Pathobiology and Population Sciences, Centre for Emerging, Endemic and Exotic Diseases (CEEED), Royal Veterinary College, University of London, Hawkshead Campus, Herts, United Kingdom
| | - David Rollinson
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, The Natural History Museum, London, United Kingdom.,London Centre for Neglected Tropical Disease Research (LCNTDR), Imperial College Faculty of Medicine, London, United Kingdom
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40
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Colley DG, Fleming FM, Matendechero SH, Knopp S, Rollinson D, Utzinger J, Castleman JD, Kittur N, King CH, Campbell CH, Kabole FM, Kinung'hi S, Ramzy RMR, Binder S. Contributions of the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) to Schistosomiasis Control and Elimination: Key Findings and Messages for Future Goals, Thresholds, and Operational Research. Am J Trop Med Hyg 2020; 103:125-134. [PMID: 32400345 PMCID: PMC7351304 DOI: 10.4269/ajtmh.19-0787] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Herein, we summarize what we consider are major contributions resulting from the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) program, including its key findings and key messages from those findings. Briefly, SCORE's key findings are as follows: i) biennial mass drug administration (MDA) with praziquantel can control schistosomiasis to moderate levels of prevalence; ii) MDA alone will not achieve elimination; iii) to attain and sustain control throughout endemic areas, persistent hotspots need to be identified following a minimal number of years of annual MDA and controlled through adaptive strategies; iv) annual MDA is more effective than biennial MDA in high-prevalence areas; v) the current World Health Organization thresholds for decision-making based on the prevalence of heavy infections should be redefined; and vi) point-of-care circulating cathodic antigen urine assays are useful for Schistosoma mansoni mapping in low-to-moderate prevalence areas. The data and specimens collected and curated through SCORE efforts will continue to be critical resource for future research. Besides providing useful information for program managers and revision of guidelines for schistosomiasis control and elimination, SCORE research and outcomes have identified additional questions that need to be answered as the schistosomiasis community continues to implement effective, evidence-based programs. An overarching contribution of SCORE has been increased cohesiveness within the schistosomiasis field-oriented community, thereby fostering new and productive collaborations. Based on SCORE's findings and experiences, we propose new approaches, thresholds, targets, and goals for control and elimination of schistosomiasis, and recommend research and evaluation activities to achieve these targets and goals.
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Affiliation(s)
- Daniel G Colley
- Department of Microbiology, University of Georgia, Athens, Georgia.,Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Fiona M Fleming
- Department of Infectious Disease Epidemiology, Schistosomiasis Control Initiative, London, United Kingdom
| | - Sultani H Matendechero
- Division of Communicable Disease Prevention and Control, Neglected Tropical Diseases Unit, Ministry of Health, Nairobi, Kenya
| | - Stefanie Knopp
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland.,Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, London, United Kingdom
| | - David Rollinson
- Department of Life Sciences, Wolfson Wellcome Biomedical Laboratories, Natural History Museum, London, United Kingdom
| | - Jürg Utzinger
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Jennifer D Castleman
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Charles H King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio.,Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Fatma M Kabole
- Neglected Diseases Programme, Ministry of Health of Zanzibar, Zanzibar, United Republic of Tanzania
| | - Safari Kinung'hi
- National Institute for Medical Research (NIMR), Mwanza Centre, Mwanza, United Republic of Tanzania
| | - Reda M R Ramzy
- National Nutrition Institute, General Organization for Teaching Hospitals and Institutes, Cairo, Egypt
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation (SCORE), Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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41
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Monnier N, Barth-Jaeggi T, Knopp S, Steinmann P. Core components, concepts and strategies for parasitic and vector-borne disease elimination with a focus on schistosomiasis: A landscape analysis. PLoS Negl Trop Dis 2020; 14:e0008837. [PMID: 33125375 PMCID: PMC7598467 DOI: 10.1371/journal.pntd.0008837] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/01/2020] [Indexed: 12/19/2022] Open
Abstract
Efforts to control and eliminate human schistosomiasis have accelerated over the past decade. In a number of endemic countries and settings, interruption of schistosome transmission has been achieved. In others, Schistosoma infections continue to challenge program managers at different levels, from the complexity of the transmission cycle, over limited treatment options and lack of field-friendly accurate diagnostics, to controversy around adequate intervention strategies. We conducted a landscape analysis on parasitic and vector-borne disease elimination approaches with the aim to identify evidence-based strategies, core components and key concepts for achieving and sustaining schistosomiasis control and for progressing elimination efforts towards interruption of transmission in sub-Saharan Africa. A total of 118 relevant publications were identified from Web of Science, Pubmed and the grey literature and reviewed for their content. In addition, we conducted in-depth interviews with 23 epidemiologists, program managers, policymakers, donors and field researchers. Available evidence emphasizes the need for comprehensive, multipronged and long-term strategies consisting of multiple complementary interventions that must be sustained over time by political commitment and adequate funding in order to reach interruption of transmission. Based on the findings of this landscape analysis, we propose a comprehensive set of intervention strategies for schistosomiasis control and elimination. Before deployment, the proposed interventions will require review, evaluation and validation in the frame of an expert consultation as a step towards adaptation to specific contexts, conditions and settings. Field testing to ensure local relevance and effectiveness is paramount given the diversity of socio-ecological and epidemiological contexts. This landscape analysis explored successful concepts, approaches and interventions of past and ongoing parasitic and vector-borne disease elimination efforts and programs with regard to relevance for progress in the elimination of human schistosome infections. Schistosomiasis is a disabling, water borne parasitic disease of public health concern with an estimated 250 million people infected worldwide. The long-term morbidity of this neglected tropical disease significantly impacts growth, cognition and socioeconomic development at all ages. Despite increased global efforts to control morbidity and advance elimination, challenges in view of the complex life cycle which involves freshwater sources, intermediate snail hosts and humans, remain. This calls for targeted interventions and concerted programs. According to the evidence from the literature and as proposed by a wide range of key informants, comprehensive, multipronged and long-term strategies supported by strong political commitment and adequate funding are required in order to achieve and sustain the set goals. Based on the findings, we propose here a comprehensive set of intervention strategies for schistosomiasis control and elimination for review and evaluation to inform implementation research needs and elimination program design.
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Affiliation(s)
- Nora Monnier
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
| | - Tanja Barth-Jaeggi
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Peter Steinmann
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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42
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Salari P, Fürst T, Knopp S, Rollinson D, Kabole F, Khamis MI, Omar MA, Bacon O, Ali SM, Utzinger J, Tediosi F. Financial Costs of the Zanzibar Elimination of Schistosomiasis Transmission Project. Am J Trop Med Hyg 2020; 103:2260-2267. [PMID: 32996446 PMCID: PMC7695112 DOI: 10.4269/ajtmh.20-0252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
We estimated the financial costs of different interventions against urogenital schistosomiasis, implemented by the Zanzibar Elimination of Schistosomiasis Transmission (ZEST) project, on Pemba and Unguja islands, Tanzania. We used available data on project activities, resources used, and costs reported in the accounting information systems of ZEST partners. The costs were estimated for all the activities related to snail control, behavior change interventions, the impact assessment surveys, and management of the whole program. Costs are presented in US$ for the full duration of the ZEST project from 2011/2012 to 2017. The total financial costs of implementing snail control activities over 5 years, excluding the costs for donated Bayluscide, were US$55,796 on Pemba and US$73,581 on Unguja, mainly driven by personnel costs. The total financial costs of implementing behavior change activities were US$109,165 on Pemba and US$155,828 on Unguja, with costs for personnel accounting for 47% on Pemba and 69% on Unguja. Costs of implementing biannual mass drug administration refer to the estimated 2.4 million treatments provided on Pemba over 4 years (2013–2016), and do not include the costs of donated praziquantel. The total cost per provided treatment was, on average, US$0.21. This study showed the value of exploiting administrative data to estimate costs of major global health interventions. It also provides an evidence base for financial costs and main cost drivers of implementing multiple combinations of intervention sets that inform decisions regarding the feasibility and affordability of implementing schistosomiasis control and elimination strategies.
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Affiliation(s)
- Paola Salari
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Thomas Fürst
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Stefanie Knopp
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | - Fatma Kabole
- Neglected Diseases Program, Zanzibar Ministry of Health, Zanzibar, Tanzania
| | - Mohammed I Khamis
- Neglected Diseases Program, Zanzibar Ministry of Health, Zanzibar, Tanzania
| | - Mussa A Omar
- Public Health Laboratory-Ivo de Carneri, Chake Chake, Tanzania
| | | | - Said M Ali
- Public Health Laboratory-Ivo de Carneri, Chake Chake, Tanzania
| | - Jürg Utzinger
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Fabrizio Tediosi
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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Analytical and Clinical Assessment of a Portable, Isothermal Recombinase Polymerase Amplification (RPA) Assay for the Molecular Diagnosis of Urogenital Schistosomiasis. Molecules 2020; 25:molecules25184175. [PMID: 32933094 PMCID: PMC7570534 DOI: 10.3390/molecules25184175] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/09/2020] [Accepted: 09/09/2020] [Indexed: 12/21/2022] Open
Abstract
Accurate diagnosis of urogenital schistosomiasis is crucial for disease surveillance and control. Routine diagnostic methods, however, lack sensitivity when assessing patients with low levels of infection still able to maintain pathogen transmission. Therefore, there is a need for highly sensitive diagnostic tools that can be used at the point-of-care in endemic areas. Recombinase polymerase amplification (RPA) is a rapid and sensitive diagnostic tool that has been used to diagnose several pathogens at the point-of-care. Here, the analytical performance of a previously developed RPA assay (RT-ShDra1-RPA) targeting the Schistosoma haematobium Dra1 genomic region was assessed using commercially synthesised S. haematobium Dra1 copies and laboratory-prepared samples spiked with S. haematobium eggs. Clinical performance was also assessed by comparing diagnostic outcomes with that of a reference diagnostic standard, urine-egg microscopy. The RT-ShDra1-RPA was able to detect 1 × 101 copies of commercially synthesised Dra1 DNA as well as one S. haematobium egg within laboratory-spiked ddH2O samples. When compared with urine-egg microscopy, the overall sensitivity and specificity of the RT-ShDra1-RPA assay was 93.7% (±88.7–96.9) and 100% (±69.1–100), respectively. Positive and negative predictive values were 100% (±97.5–100) and 50% (±27.2–72.8), respectively. The RT-ShDra1-RPA therefore shows promise as a rapid and highly sensitive diagnostic tool able to diagnose urogenital schistosomiasis at the point-of-care.
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Keller D, Rothen J, Dangy JP, Saner C, Daubenberger C, Allan F, Ame SM, Ali SM, Kabole F, Hattendorf J, Rollinson D, Seyfarth R, Knopp S. Performance of a real-time PCR approach for diagnosing Schistosoma haematobium infections of different intensity in urine samples from Zanzibar. Infect Dis Poverty 2020; 9:128. [PMID: 32887642 PMCID: PMC7487541 DOI: 10.1186/s40249-020-00726-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/14/2020] [Indexed: 12/17/2022] Open
Abstract
Background Efforts to control and eliminate schistosomiasis have accelerated over the past decade. As parasite burden, associated morbidity and egg excretion decrease, diagnosis with standard parasitological methods becomes harder. We assessed the robustness and performance of a real-time PCR (qPCR) approach in comparison with urine filtration microscopy and reagent strip testing for the diagnosis of Schistosoma haematobium infections of different intensities. Methods The robustness of DNA isolation and qPCR was validated in eight laboratories from Europe and Africa. Subsequently, 792 urine samples collected during cross-sectional surveys of the Zanzibar Elimination of Schistosomiasis Transmission (ZEST) project in 2012–2017 were examined with qPCR in 2018. Diagnostic sensitivity of the qPCR was calculated at different infection intensity categories, using urine filtration microscopy as reference test. Spearman’s rank correlation between Ct-values and S. haematobium egg counts was assessed and Ct-value percentiles for infection intensity categories determined. Results S. haematobium Dra1 DNA-positive samples were identified correctly in all eight laboratories. Examination of urine samples from Zanzibar revealed Dra1 DNA in 26.8% (212/792) by qPCR, S. haematobium eggs in 13.3% (105/792) by urine filtration, and microhaematuria in 13.8% (109/792) by reagent strips. Sensitivity of the qPCR increased with augmenting egg counts: 80.6% (29/36) for counts between 1 and 4 eggs, 83.3% (15/18) for counts between 5 and 9 eggs, 100% (23/23) for counts between 10 and 49 eggs, and 96.4% (27/28) for counts of 50+ eggs. There was a significant negative correlation between Ct-values and egg counts (Spearman’s rho = − 0.49, P < 0.001). Seventy-five percent of the Ct-values were ≥ 33 in the egg-negative category, < 31 in the light intensity category, and < 24 in the heavy intensity category. Conclusions While the sensitivity of the qPCR was ~ 80% for very light intensity infections (egg counts < 10), in general, the Dra1 based qPCR assay detected twice as many S. haematobium infections compared with classical parasitological tests. The qPCR is hence a sensitive, urine-based approach for S. haematobium diagnosis that can be used for impact assessment of schistosomiasis elimination programmes, individual diagnosis, and in improved format also for verification and certification of elimination. Trial registration ISRCTN, ISRCTN48837681. Registered 05 September 2012 - Retrospectively registered.
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Affiliation(s)
| | - Julian Rothen
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Corina Saner
- Biolytix AG, Benkenstrasse 254, 4108, Witterswil, Switzerland
| | - Claudia Daubenberger
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Fiona Allan
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
| | - Shaali M Ame
- Public Health Laboratory Ivo de Carneri, P.O. Box 122, Chake-Chake, Pemba, United Republic of Tanzania
| | - Said M Ali
- Public Health Laboratory Ivo de Carneri, P.O. Box 122, Chake-Chake, Pemba, United Republic of Tanzania
| | - Fatma Kabole
- Neglected Diseases Programme, Ministry of Health, P.O. Box 236, Zanzibar Town, Unguja, United Republic of Tanzania
| | - Jan Hattendorf
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland.,University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
| | - Ralf Seyfarth
- Biolytix AG, Benkenstrasse 254, 4108, Witterswil, Switzerland
| | - Stefanie Knopp
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002, Basel, Switzerland. .,University of Basel, Petersplatz 1, 4001, Basel, Switzerland.
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45
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Turner HC, French MD, Montresor A, King CH, Rollinson D, Toor J. Economic evaluations of human schistosomiasis interventions: a systematic review and identification of associated research needs. Wellcome Open Res 2020; 5:45. [PMID: 32587899 PMCID: PMC7308887 DOI: 10.12688/wellcomeopenres.15754.2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2020] [Indexed: 12/12/2022] Open
Abstract
Background: Schistosomiasis is one of the most prevalent neglected tropical diseases (NTDs) with an estimated 229 million people requiring preventive treatment worldwide. Recommendations for preventive chemotherapy strategies have been made by the World Health Organization (WHO) whereby the frequency of treatment is determined by the settings prevalence. Despite recent progress, many countries still need to scale up treatment and important questions remain regarding optimal control strategies. This paper presents a systematic review of the economic evaluations of human schistosomiasis interventions. Methods: A systematic review of the literature was conducted on 22nd August 2019 using the PubMed (MEDLINE) and ISI Web of Science electronic databases. The focus was economic evaluations of schistosomiasis interventions, such as cost-effectiveness and cost-benefit analyses. No date or language stipulations were applied to the searches. Results: We identified 53 relevant health economic analyses of schistosomiasis interventions. Most studies related to Schistosoma japonicum followed by S. haematobium. Several studies also included other NTDs. In Africa, most studies evaluated preventive chemotherapy, whereas in China they mostly evaluated programmes using a combination of interventions (such as chemotherapy, snail control and health education). There was wide variation in the methodology and epidemiological settings investigated. A range of effectiveness metrics were used by the different studies. Conclusions: Due to the variation across the identified studies, it was not possible to make definitive policy recommendations. Although, in general, the current WHO recommended preventive chemotherapy approach to control schistosomiasis was found to be cost-effective. This finding has important implications for policymakers, advocacy groups and potential funders. However, there are several important inconsistencies and research gaps (such as how the health benefits of interventions are quantified) that need to be addressed to identify the resources required to achieve schistosomiasis control and elimination.
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Affiliation(s)
- Hugo C. Turner
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Faculty of Medicine, St Mary’s Campus, Imperial College London, London, W2 1PG, UK
- Oxford University Clinical Research Unit, Wellcome Africa Asia Programme, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Antonio Montresor
- Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Charles H. King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, USA
| | - David Rollinson
- Global Schistosomiasis Alliance, Natural History Museum, London, UK
| | - Jaspreet Toor
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
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Husein‐ElAhmed H, Gieler U, Steinhoff M. Evidence supporting the enhanced efficacy of pentavalent antimonials with adjuvant therapy for cutaneous leishmaniasis: a systematic review and meta‐analysis. J Eur Acad Dermatol Venereol 2020; 34:2216-2228. [DOI: 10.1111/jdv.16333] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 02/10/2020] [Indexed: 11/29/2022]
Affiliation(s)
- H. Husein‐ElAhmed
- Department of Dermatology and Venereology Hospital de Baza Granada Spain
- Translational Research Institute Academic Health System Medical School Hamad Medical Corporation Doha Qatar
| | - U. Gieler
- Translational Research Institute Academic Health System Medical School Hamad Medical Corporation Doha Qatar
- Department of Dermatology and Venereology Hamad Medical Corporation Doha Qatar
| | - M. Steinhoff
- Translational Research Institute Academic Health System Medical School Hamad Medical Corporation Doha Qatar
- Department of Dermatology and Venereology Hamad Medical Corporation Doha Qatar
- College of Medicine Weill Cornell Medicine‐Qatar Doha Qatar
- Medical School Qatar University Doha Qatar
- College of Medicine Weill Cornell University New York NY USA
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Allan F, Ame SM, Tian-Bi YNT, Hofkin BV, Webster BL, Diakité NR, N’Goran EK, Kabole F, Khamis IS, Gouvras AN, Emery AM, Pennance T, Rabone M, Kinung’hi S, Hamidou AA, Mkoji GM, McLaughlin JP, Kuris AM, Loker ES, Knopp S, Rollinson D. Snail-Related Contributions from the Schistosomiasis Consortium for Operational Research and Evaluation Program Including Xenomonitoring, Focal Mollusciciding, Biological Control, and Modeling. Am J Trop Med Hyg 2020; 103:66-79. [PMID: 32400353 PMCID: PMC7351297 DOI: 10.4269/ajtmh.19-0831] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/14/2020] [Indexed: 01/05/2023] Open
Abstract
The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was created in 2008 to answer questions of importance to program managers working to reduce the burden of schistosomiasis in Africa. In the past, intermediate host snail monitoring and control was an important part of integrated schistosomiasis control. However, in Africa, efforts to control snails have declined dramatically over the last 30 years. A resurgence of interest in the control of snails has been prompted by the realization, backed by a World Health Assembly resolution (WHA65.21), that mass drug administration alone may be insufficient to achieve schistosomiasis elimination. SCORE has supported work on snail identification and mapping and investigated how xenomonitoring techniques can aid in the identification of infected snails and thereby identify potential transmission areas. Focal mollusciciding with niclosamide was undertaken in Zanzibar and Côte d'Ivoire as a part of elimination studies. Two studies involving biological control of snails were conducted: one explored the association of freshwater riverine prawns and snail hosts in Côte d'Ivoire and the other assessed the current distribution of Procambarus clarkii, the invasive Louisiana red swamp crayfish, in Kenya and its association with snail hosts and schistosomiasis transmission. SCORE also supported modeling studies on the importance of snail control in achieving elimination and a meta-analysis of the impact of molluscicide-based snail control programs on human schistosomiasis prevalence and incidence. SCORE's snail control studies contributed to increased investment in building capacity, and specimens collected during SCORE research deposited in the Schistosomiasis Collections at the Natural History Museum (SCAN) will provide a valuable resource for the years to come.
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Affiliation(s)
- Fiona Allan
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Shaali M. Ame
- Public Health Laboratory - Ivo de Carneri, Pemba, United Republic of Tanzania
| | - Yves-Nathan T. Tian-Bi
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Bruce V. Hofkin
- Department of Biology, University of New Mexico, Albuquerque, New Mexico
| | - Bonnie L. Webster
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Nana R. Diakité
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Eliezer K. N’Goran
- Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d’Ivoire
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Fatma Kabole
- Neglected Tropical Disease Unit, Unguja, Ministry of Health, Zanzibar, United Republic of Tanzania
| | - Iddi S. Khamis
- Neglected Tropical Disease Unit, Unguja, Ministry of Health, Zanzibar, United Republic of Tanzania
| | - Anouk N. Gouvras
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Aidan M. Emery
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Tom Pennance
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Muriel Rabone
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Safari Kinung’hi
- National Institute of Medical Research (NIMR) Mwanza Centre, Mwanza, United Republic of Tanzania
| | - Amina Amadou Hamidou
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), Niamey, Niger
| | - Gerald M. Mkoji
- Center for Biotechnology Research and Development, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
| | - John P. McLaughlin
- Department of Ecology, Evolution and Marine Biology and Marine Science Institute, University of California, Santa Barbara, California
| | - Armand M. Kuris
- Department of Ecology, Evolution and Marine Biology and Marine Science Institute, University of California, Santa Barbara, California
| | - Eric S. Loker
- Department of Biology, University of New Mexico, Albuquerque, New Mexico
| | - Stefanie Knopp
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
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Sturt AS, Webb EL, Phiri CR, Mweene T, Chola N, van Dam GJ, Corstjens PLAM, Wessels E, Stothard JR, Hayes R, Ayles H, Hansingo I, van Lieshout L, Bustinduy AL. Genital self-sampling compared with cervicovaginal lavage for the diagnosis of female genital schistosomiasis in Zambian women: The BILHIV study. PLoS Negl Trop Dis 2020; 14:e0008337. [PMID: 32663222 PMCID: PMC7360036 DOI: 10.1371/journal.pntd.0008337] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 04/29/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Given the potentially causal association of female genital schistosomiasis (FGS) with HIV-1 infection, improved diagnostics are urgently needed to scale-up FGS surveillance. The BILHIV (bilharzia and HIV) study assessed the performance of home-based self-collection methods (cervical and vaginal swabs) compared to cervicovaginal lavage (CVL) for the detection of Schistosoma DNA by real-time polymerase chain reaction (PCR). METHODS Between January and August 2018, a consecutive series of female participants from the Population-Cohort of the previous HIV prevention trial HPTN 071 (PopART), resident in Livingstone, Zambia were invited to take part in BILHIV if they were 18-31 years old, non-pregnant and sexually active. Genital self-collected swabs and a urine specimen were obtained and a questionnaire completed at home visits. CVL was obtained at clinic follow-up. RESULTS 603 women self-collected genital swabs. Of these, 527 women had CVL performed by a mid-wife during clinic follow-up. Schistosoma DNA was more frequently detected in genital self-collected specimens (24/603, 4.0%) compared to CVL (14/527, 2.7%). Overall, 5.0% (30/603) women had female genital schistosomiasis, defined as a positive PCR by any genital sampling method (cervical swab PCR, vaginal swab PCR, or CVL PCR) and 95% (573/603) did not have a positive genital PCR. The sensitivity of any positive genital self-collected swab against CVL was 57.1% (95% CI 28.9-82.3%), specificity 97.3% (95.5-98.5%). In a subset of participants with active schistosome infection, determined by detectable urine Circulating Anodic Antigen (CAA) (15.1%, 91/601), positive PCR (4.3%, 26/601), or positive microscopy (5.5%, 33/603), the sensitivity of any positive self-collected specimen against CVL was 88.9% (51.8-99.7%). CONCLUSIONS Genital self-sampling increased the overall number of PCR-based FGS diagnoses in a field setting, compared with CVL. Home-based sampling may represent a scalable alternative method for FGS community-based diagnosis in endemic resource limited settings.
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Affiliation(s)
- Amy S. Sturt
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Emily L. Webb
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | | | - Govert J. van Dam
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Paul L. A. M. Corstjens
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Els Wessels
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - J. Russell Stothard
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Richard Hayes
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Helen Ayles
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Zambart, Lusaka, Zambia
| | - Isaiah Hansingo
- Department of Obstetrics and Gynaecology, Livingstone Central Hospital, Livingstone, Zambia
| | - Lisette van Lieshout
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Amaya L. Bustinduy
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
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King CH, Kittur N, Wiegand RE, Shen Y, Ge Y, Whalen CC, Campbell CH, Hattendorf J, Binder S. Challenges in Protocol Development and Interpretation of the Schistosomiasis Consortium for Operational Research and Evaluation Intervention Studies. Am J Trop Med Hyg 2020; 103:36-41. [PMID: 32400342 PMCID: PMC7351306 DOI: 10.4269/ajtmh.19-0805] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In 2010, the Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) began the design of randomized controlled trials to compare different strategies for praziquantel mass drug administration, whether for gaining or sustaining control of schistosomiasis or for approaching local elimination of Schistosoma transmission. The goal of this operational research was to expand the evidence base for policy-making for regional and national control of schistosomiasis in sub-Saharan Africa. Over the 10-year period of its research programs, as SCORE operational research projects were implemented, their scope and scale posed important challenges in terms of research performance and the final interpretation of their results. The SCORE projects yielded valuable data on program-level effectiveness and strengths and weaknesses in performance, but in most of the trials, a greater-than-expected variation in community-level responses to assigned schedules of mass drug administration meant that identification of a dominant control strategy was not possible. This article critically reviews the impact of SCORE’s cluster randomized study design on performance and interpretation of large-scale operational research such as ours.
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Affiliation(s)
- Charles H King
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia.,Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio
| | - Nupur Kittur
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Ryan E Wiegand
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland.,Parasitic Diseases Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Ye Shen
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, Georgia
| | - Yang Ge
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, Georgia
| | - Christopher C Whalen
- Department of Epidemiology & Biostatistics, University of Georgia, Athens, Georgia
| | - Carl H Campbell
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
| | - Jan Hattendorf
- University of Basel, Basel, Switzerland.,Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Sue Binder
- Schistosomiasis Consortium for Operational Research and Evaluation, Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia
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Impacts of host gender on Schistosoma mansoni risk in rural Uganda-A mixed-methods approach. PLoS Negl Trop Dis 2020; 14:e0008266. [PMID: 32401770 PMCID: PMC7219705 DOI: 10.1371/journal.pntd.0008266] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 04/02/2020] [Indexed: 12/12/2022] Open
Abstract
Background The World Health Organization identified Uganda as one of the 10 highly endemic countries for schistosomiasis. Annual mass drug administration (MDA) with praziquantel has led to a decline in intensity of Schistosoma mansoni infections in several areas. However, as hotspots with high (re)infection rates remain, additional research on risk factors and implementing interventions to complement MDA are required to further reduce disease burden in these settings. Through a mixed-methods study we aimed to gain deeper understanding of how gender may impact risk and reinfection in order to inform disease control programmes and ascertain if gender-specific interventions may be beneficial. Methodology/Principal findings In Bugoto, Mayuge District, Eastern Uganda we conducted ethnographic observations (n = 16) and examined epidemiology (n = 55) and parasite population genetics (n = 16) in school-aged children (SAC), alongside a community-wide household survey (n = 130). Water contact was frequent at home, school and in the community and was of domestic, personal care, recreational, religious or commercial nature. Qualitative analysis of type of activity, duration, frequency, level of submersion and water contact sites in children showed only few behavioural differences in water contact between genders. However, survey data revealed that adult women carried out the vast majority of household tasks involving water contact. Reinfection rates (96% overall) and genetic diversity were high in boys (pre-He = 0.66; post-He = 0.67) and girls (pre-He = 0.65; post-He = 0.67), but no differences in reinfection rates (p = 0.62) or genetic diversity by gender before (p = 0.54) or after (p = 0.97) treatment were found. Conclusions/Significance This mixed methods approach showed complementary findings. Frequent water exposure with few differences between boys and girls was mirrored by high reinfection rates and genetic diversity in both genders. Disease control programmes should consider the high reinfection rates among SAC in remaining hotspots of schistosomiasis and the various purposes and settings in which children and adults are exposed to water. Globally, over 230 million people are infected with schistosomiasis, an infectious disease caused by parasitic helminths. Humans can get infected when they contact water which contains Schistosoma parasites. Although the disease can be treated with a drug, people get rapidly reinfected in certain high-transmission settings. Drug treatment alone may not be sufficient to eliminate this disease and additional interventions such as health promotion or improvements in water and sanitation need to be scaled up. To provide recommendations to these control programmes we carried out interdisciplinary research in Eastern Uganda to understand the influence of gender on schistosomiasis risk. We found that the water contact behaviour of boys and girls is quite similar, and we did not see differences in reinfection or genetic diversity of the parasite between boys and girls. Differences in water contact between genders is greater in adults, and further research is required for these individuals. In this setting, infection rates are high in school-aged children and there are no differences between genders. These results emphasise improved control efforts for all school-aged children in communities like these. Our interdisciplinary approach provided complementary findings. Such an integrated approach can therefore have more power to meaningfully inform policy on schistosomiasis control.
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