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Salim Masoud N, Knopp S, Lenz N, Lweno O, Abdul Kibondo U, Mohamed A, Schindler T, Rothen J, Masimba J, S. Mohammed A, Althaus F, Abdulla S, Tanner M, Daubenberger C, Genton B. The impact of soil transmitted helminth on malaria clinical presentation and treatment outcome: A case control study among children in Bagamoyo district, coastal region of Tanzania. PLoS Negl Trop Dis 2024; 18:e0012412. [PMID: 39133750 PMCID: PMC11341094 DOI: 10.1371/journal.pntd.0012412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 08/22/2024] [Accepted: 07/29/2024] [Indexed: 08/24/2024] Open
Abstract
BACKGROUND Parasitic infectious agents rarely occur in isolation. Epidemiological evidence is mostly lacking, and little is known on how the two common parasites Plasmodium and soil transmitted helminths (STH) interact. There are contradictory findings in different studies. Synergism, antagonism and neutral effect have been documented between Plasmodium and STH. This study investigated the impact of STH on clinical malaria presentation and treatment outcome. METHODS A matched case control study with a semi longitudinal follow up according to World Health Organization (WHO) antimalarial surveillance guideline was done among children aged 2 months to 9 years inclusively living in western rural areas of Bagamoyo, coastal region of Tanzania. Cases were children with uncomplicated and severe malaria enrolled from the health facilities while controls were children with asymptomatic Plasmodium parasitemia enrolled from the same community. RESULTS In simple conditional regression analysis there was a tendency for a protective effect of STH on the development of clinical malaria [OR = 0.6, 95% CI of 0.3-1.3] which was more marked for Enterobius vermicularis species [OR = 0.2, 95% CI of 0.0-0.9]. On the contrary, hookworm species tended to be associated with increased risk of clinical malaria [OR = 3.0, 95% CI of 0.9-9.5]. In multiple conditional regression analysis, the overall protective effect was lower for all helminth infection [OR = 0.8, 95% CI of 0.3-1.9] but remained significantly protective for E. vermicularis species [OR = 0.1, 95% CI of 0.0-1.0] and borderline significant for hookworm species [OR = 3.6, 95% CI of 0.9-14.3]. Using ordinal logistic regression which better reflects the progression of asymptomatic Plasmodium parasitemia to severe malaria, there was a 50% significant protective effect with overall helminths [OR = 0.5, 95% CI of 0.3-0.9]. On the contrary, hookworm species was highly predictive of uncomplicated and severe malaria [OR = 7.8, 95% (CI of 1.8-33.9) and 49.7 (95% CI of 1.9-1298.9) respectively]. Generally, children infected with STH had higher geometric mean time to first clearance of parasitemia. CONCLUSION The findings of a protective effect of E. vermicularis and an enhancing effect of hookworms may explain the contradictory results found in the literature about impact of helminths on clinical malaria. More insight should be gained on possible mechanisms for these opposite effects. These results should not deter at this stage deworming programs but rather foster implementation of integrated control program for these two common parasites.
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Affiliation(s)
- Nahya Salim Masoud
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
- Department of Pediatrics and Child Health, Muhimbili University Health and Allied Sciences (MUHAS), Dar es Salaam, United Republic of Tanzania
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Stefanie Knopp
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nicole Lenz
- Food Microbial Systems, Risk Assessment and Mitigation Group, Agroscope, Bern, Switzerland
| | - Omar Lweno
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Ummi Abdul Kibondo
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Ali Mohamed
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Tobias Schindler
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
- University of Basel, Basel, Switzerland
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Julian Rothen
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
- University of Basel, Basel, Switzerland
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - John Masimba
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Alisa S. Mohammed
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Fabrice Althaus
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- Health Unit, International Committee of the Red Cross (ICRC), Geneva, Switzerland
| | - Salim Abdulla
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, United Republic of Tanzania
| | - Marcel Tanner
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Claudia Daubenberger
- University of Basel, Basel, Switzerland
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Blaise Genton
- Department of Ambulatory Care and Community Medicine, University of Lausanne, Lausanne, Switzerland
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Duguay C, Raduy S, Khov E, Protopopoff N, Feng C, Krentel A, Kulkarni MA. Have there been efforts to integrate malaria and schistosomiasis prevention and control programs? A scoping review of the literature. PLoS Negl Trop Dis 2024; 18:e0011886. [PMID: 38265982 PMCID: PMC10807771 DOI: 10.1371/journal.pntd.0011886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 12/27/2023] [Indexed: 01/26/2024] Open
Abstract
Malaria and schistosomiasis are two important parasitic diseases that are a particular threat to young children and pregnant women in sub-Saharan Africa. Malaria and schistosomiasis prevention and control strategies primarily focus on the distribution of long-lasting insecticidal nets and the delivery of praziquantel tablets to at-risk populations in high burden settings through mass drug administration, respectively. The objective of this scoping review was to identify previous efforts to integrate malaria and schistosomiasis prevention and control programs in the literature and to summarize the strategies and approaches used in these programs following the PRISMA-ScR guidelines. We reviewed published and grey literature using a combination of keywords and search terms following themes surrounding "malaria", "Plasmodium falciparum", "Anopheles", "schistosomiasis", "Schistosoma haematobium", "Schistosoma mansoni", and "snails". Neither a date limit nor relevant terms for prevention and control were used. Out of 6374, eight articles were included in the scoping review-three articles investigated the integration of mass drug administration for schistosomiasis with the administration of antimalarials, four articles investigated the effect of administering antimalarials on malaria, schistosomiasis, and their co-infection, and one article assessed the impact of an educational intervention on malaria and schistosomiasis knowledge and preventative behaviors. Our findings suggest that there is an opportunity to link disease control programs to increase access and coverage of interventions to improve outcomes for malaria, schistosomiasis, and their co-infection. Further research is needed on the potential benefits, feasibility, and cost-effectiveness of integrating malaria and schistosomiasis prevention and control programs.
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Affiliation(s)
- Claudia Duguay
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | - Sydney Raduy
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | - Engluy Khov
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
| | | | - Cindy Feng
- Department of Community Health & Epidemiology, Dalhousie University, Halifax, Canada
| | - Alison Krentel
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Bruyère Research Institute, Ottawa, Ontario, Canada
| | - Manisha A. Kulkarni
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
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Kibondo UA, Renju J, Lukole E, Mosha JF, Mosha FW, Manjurano A, Rowland M, Protopopoff N. Factors associated with malaria infection among children after distribution of PBO-pyrethroid synergist-treated nets and indoor residual spraying in north-western Tanzania. PLoS One 2023; 18:e0295800. [PMID: 38127909 PMCID: PMC10734997 DOI: 10.1371/journal.pone.0295800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND After a decade of successful control, malaria is on the rise again. The prevalence of malaria in Tanzania has increased from 7% in 2017 to 8% in 2022 and reached 18% in Kagera region in the North West of Tanzania. Malaria vectors in Muleba district Kagera have high level of pyrethroid resistance. The aim of this paper is to explore factors associated with malaria infection prevalence in children aged 6 months to 14 years in Muleba, where Long Lasting Insecticidal Net (LLIN) combining a pyrethroid insecticide and synergist piperonyl butoxide (PBO) that counteract resistance in the mosquitoes, was first distributed under trial conditions in 2015. METHODS The trial was a community randomized control in which there were two malaria prevalence cross-sectional household surveys each year (June and December) from 2015 to 2017 in Muleba. In this study we conducted a secondary data analysis of the December surveys only. Multilevel Poisson regression analysis was used to assess factors associated with malaria infection. RESULTS A total of 10,941 children and 4,611 households were included in this study. Overall malaria prevalence was 35.8%, 53.3% and 54.4% in the year 2015, 2016 and 2017 respectively. Living in an area with standard LLIN as opposed to the novel PBO synergist LLIN, being a male child, above 5 years of age, living in a house with open eaves, living in house without IRS, having head of household with no formal education, lower socioeconomic status and survey year were associated with increased risk of malaria infection. CONCLUSIONS Using PBO LLIN reduced the risk of malaria infection. However, additional measures could further reduce malaria infection in areas of insecticide resistance such as housing improvement.
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Affiliation(s)
- Ummi Abdul Kibondo
- Vector Control Product Testing Unit (VCPTU) Ifakara Health Institute, Environmental Health, and Ecological Sciences, Bagamoyo, Tanzania
- Department of Epidemiology and Biostatistics, Institute of Public Health, Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
| | - Jenny Renju
- Department of Epidemiology and Biostatistics, Institute of Public Health, Kilimanjaro Christian Medical University College (KCMUCo), Moshi, Tanzania
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Eliud Lukole
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Jacklin F. Mosha
- National Institute for Medical Research, Mwanza Medical Research Centre, Mwanza, Tanzania
| | | | - Alphaxard Manjurano
- National Institute for Medical Research, Mwanza Medical Research Centre, Mwanza, Tanzania
| | - Mark Rowland
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
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Silk SE, Kalinga WF, Mtaka IM, Lilolime NS, Mpina M, Milando F, Ahmed S, Diouf A, Mkwepu F, Simon B, Athumani T, Rashid M, Mohammed L, Lweno O, Ali AM, Nyaulingo G, Mwalimu B, Mswata S, Mwamlima TG, Barrett JR, Wang LT, Themistocleous Y, King LDW, Hodgson SH, Payne RO, Nielsen CM, Lawrie AM, Nugent FL, Cho JS, Long CA, Miura K, Draper SJ, Minassian AM, Olotu AI. Superior antibody immunogenicity of a viral-vectored RH5 blood-stage malaria vaccine in Tanzanian infants as compared to adults. MED 2023; 4:668-686.e7. [PMID: 37572659 DOI: 10.1016/j.medj.2023.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/23/2023] [Accepted: 07/11/2023] [Indexed: 08/14/2023]
Abstract
BACKGROUND RH5 is a leading blood-stage candidate antigen for a Plasmodium falciparum vaccine; however, its safety and immunogenicity in malaria-endemic populations are unknown. METHODS A phase 1b, single-center, dose-escalation, age-de-escalation, double-blind, randomized, controlled trial was conducted in Bagamoyo, Tanzania (NCT03435874). Between 12th April and 25th October 2018, 63 healthy adults (18-35 years), young children (1-6 years), and infants (6-11 months) received a priming dose of viral-vectored ChAd63 RH5 or rabies control vaccine. Sixty participants were boosted with modified vaccinia virus Ankara (MVA) RH5 or rabies control vaccine 8 weeks later and completed 6 months of follow-up post priming. Primary outcomes were the number of solicited and unsolicited adverse events post vaccination and the number of serious adverse events over the study period. Secondary outcomes included measures of the anti-RH5 immune response. FINDINGS Vaccinations were well tolerated, with profiles comparable across groups. No serious adverse events were reported. Vaccination induced RH5-specific cellular and humoral responses. Higher anti-RH5 serum immunoglobulin G (IgG) responses were observed post boost in young children and infants compared to adults. Vaccine-induced antibodies showed growth inhibition activity (GIA) in vitro against P. falciparum blood-stage parasites; their highest levels were observed in infants. CONCLUSIONS The ChAd63-MVA RH5 vaccine shows acceptable safety and reactogenicity and encouraging immunogenicity in children and infants residing in a malaria-endemic area. The levels of functional GIA observed in RH5-vaccinated infants are the highest reported to date following human vaccination. These data support onward clinical development of RH5-based blood-stage vaccines to protect against clinical malaria in young African infants. FUNDING Medical Research Council, London, UK.
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Affiliation(s)
- Sarah E Silk
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Wilmina F Kalinga
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Ivanny M Mtaka
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Nasoro S Lilolime
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Maximillian Mpina
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Florence Milando
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Saumu Ahmed
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Ababacar Diouf
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, MD 20852, USA
| | - Fatuma Mkwepu
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Beatus Simon
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Thabit Athumani
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Mohammed Rashid
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Latipha Mohammed
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Omary Lweno
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Ali M Ali
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Gloria Nyaulingo
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Bakari Mwalimu
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Sarah Mswata
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Tunu G Mwamlima
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
| | - Jordan R Barrett
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Lawrence T Wang
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Yrene Themistocleous
- Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK
| | - Lloyd D W King
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Susanne H Hodgson
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Ruth O Payne
- Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK
| | - Carolyn M Nielsen
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Alison M Lawrie
- Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK
| | - Fay L Nugent
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK
| | - Jee-Sun Cho
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK
| | - Carole A Long
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, MD 20852, USA
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, NIAID/NIH, Rockville, MD 20852, USA
| | - Simon J Draper
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Angela M Minassian
- Department of Biochemistry, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; Centre for Clinical Vaccinology and Tropical Medicine, Jenner Institute, University of Oxford, Old Road Campus, Oxford OX3 7LE, UK; Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, Oxford OX1 3QU, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK.
| | - Ally I Olotu
- Interventions and Clinical Trials Department, Ifakara Health Institute, P.O. Box 74, Bagamoyo, Tanzania
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Mwangonela ZE, Ye Y, Rachel Q, Msuya HM, Mwamlima TG, Mswata SS, Chaki PP, Kimaro EG, Mweya CN, Mpina MG, Mwangoka GW. Field evaluation of the novel One Step Malaria Pf and Pf/Pv rapid diagnostic tests and the proportion of HRP-2 gene deletion identified on samples collected in the Pwani region, Tanzania. BULLETIN OF THE NATIONAL RESEARCH CENTRE 2023; 47:17. [PMID: 36776799 PMCID: PMC9904258 DOI: 10.1186/s42269-023-00992-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Background Malaria rapid diagnostic tests (mRDTs) have played an important role in the early detection of clinical malaria in an endemic area. While several mRDTs are currently on the market, the availability of mRDTs with high sensitivity and specificity will merit the fight against malaria. We evaluated the field performance of a novel One Step Malaria (P.f/P.v) Tri-line and One Step Malaria (P.f) rapid test kits in Pwani, Tanzania. Methods In a cross-sectional study conducted in Bagamoyo and Kibiti districts in Tanzania, symptomatic patients were tested using the SD BIOLINE, One Step Malaria (P.f/P.v) Tri-line and One Step Malaria (P.f) rapid test kits, microscope, and quantitative Polymerase Chain Reaction (qPCR). An additional qPCR assay was carried out to detect Histidine-Rich Protein 2 (HRP-2) gene deletion on mRDT negative but microscope and qPCR positive samples. Microscope results confirmed by qPCR were used for analysis, where qPCR was used as a reference method. Results The sensitivity and specificity of One Step P.f/P.v Tri-line mRDTs were 96.0% (CI 93.5-97.7%) and 98.3% (CI 96.8-99.2%), respectively. One Step P.f mRDT had sensitivity and specificity of 95.2% (CI 92.5-97.1%) and 97.9% (CI 96.3-99.0%) respectively. Positive predictive value (PPV) was 97.6% (CI 95.4-98.7%) and negative predictive value (NPV) was 96.2% (CI 95.5-98.3%) for the One Step P.f/P.v Tri-line mRDTs respectively, while One Step P.f mRDT had positive predictive value (PPV) and negative predictive value (NPV) of 97.0% (CI 94.8-98.3%) and 96.7 (CI 94.9-97.9%) respectively. 9.8% (CI 7.84-11.76) of all samples tested and reported to be malaria-negative by mRDT had HRP-2 gene deletion. Conclusion One Step Malaria P.f/P.v Tri-line and One Step Malaria P.f rapid test kits have similar sensitivity and specificity as the standard mRDT that is currently in the market, demonstrating the potential to contribute in the fight against malaria in endemic settings. However, the identified malaria parasites population with HRP-2 gene deletion pose a threat to the current mRDT usability in the field and warrants further investigations.
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Affiliation(s)
- Zena E. Mwangonela
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
- The Nelson Mandela African Institution of Science and Technology, P.O.Box 447, Arusha, Tanzania
| | - Young Ye
- InTec Products, Inc., 332 Xinguang Road Xinyang Industrial Area, Haicang, Xiamen City, 361022 China
| | - Qin Rachel
- InTec Products, Inc., 332 Xinguang Road Xinyang Industrial Area, Haicang, Xiamen City, 361022 China
| | - Hajirani M. Msuya
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
| | - Tunu G. Mwamlima
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
- The Nelson Mandela African Institution of Science and Technology, P.O.Box 447, Arusha, Tanzania
| | - Sarah S. Mswata
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
| | - Prosper P. Chaki
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
| | - Ester G. Kimaro
- The Nelson Mandela African Institution of Science and Technology, P.O.Box 447, Arusha, Tanzania
| | - Clement N. Mweya
- Univesity of Dar Es Salaam, Mbeya College of Health and Allied Science, P.O.Box 608, Mbeya, Tanzania
| | | | - Grace W. Mwangoka
- Ifakara Health Institute Bagamoyo Branch, P.O.Box 74, Bagamoyo, Tanzania
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Afolabi MO, Sow D, Mbaye I, Diouf MP, Loum MA, Fall EB, Seck A, Manga IA, Cissé C, Camara B, Diouf A, Gaye NA, Colle Lo A, Greenwood B, Ndiaye JLA. Prevalence of malaria-helminth co-infections among children living in a setting of high coverage of standard interventions for malaria and helminths: Two population-based studies in Senegal. Front Public Health 2023; 11:1087044. [PMID: 36935683 PMCID: PMC10018210 DOI: 10.3389/fpubh.2023.1087044] [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: 11/01/2022] [Accepted: 02/14/2023] [Indexed: 03/06/2023] Open
Abstract
Background Concurrent infections of Plasmodium falciparum with Soil Transmitted Helminths (STH) and Schistosoma spp are still a major public health problem among children living in Sub-Saharan Africa. We conducted two prospective studies among children living in urban and rural settings of Senegal, where control programmes for malaria, STH and schistosomiasis have been sustained, to determine the prevalence of malaria-helminth co-infection. Methods We enrolled 910 children aged 1-14 years from Saraya and Diourbel districts of Senegal in June and November 2021, respectively. We collected finger-prick blood samples from the children for malaria parasite detection using microscopy and PCR methods. Stool samples were also collected and Kato-Katz and PCR methods were used to detect STH and S. mansoni; and Merthiolate-iodine-formalin (MIF) test for other intestinal protozoans. Urine samples were analyzed using a filtration test, Point of Care Circulating Cathodic Antigens (POC-CCA) and PCR methods for detection of S. haematobium. Statistical analyses were performed to compare the continuous and categorical variables across the two study sites and age groups, as well as using the adjusted Odds ratios (aOR) to explore risk factors for malaria-helminth co-infections. Results The overall prevalence of polyparasitism with P. falciparum, STH, S. haematobium and S. mansoni among children in the two study sites was 2.2% (20/910) while prevalence of P. falciparum-S. haematobium co-infection was 1.1% (10/910); P. falciparum-S. mansoni 0.7% (6/910) and P. falciparum with any intestinal protozoan 2.4% (22/910). Co-infection was slightly higher among 5-14 year old children (17/629, 2.7%; 95% CI: 1.43-3.97) than 1-4 years (3/281, 1.1%; 95% CI: -0.12-2.32) and, in boys (13/567, 2.3%; 95% CI: 1.27-3.96) than girls (7/343, 2.1%; 95% CI: 0.52-3.48). Children aged 5-14 years (aOR = 3.37; 95% CI: 0.82-13.77, p = 0.09), who were boys (aOR = 1.44; 95% CI: 0.48-4.36, p = 0.51) and lived in Saraya (aOR = 1.27; 95% CI: 0.24-6.69, p = 0.77) had a higher risk of malaria-helminth co-infection than other age group, in girls and those who lived in Diourbel. Living in houses with spaces between the walls and roofs as well as frequent contacts with water during swimming were statistically significant risk factors for malaria-helminth co-infection. Conclusions The prevalence of malaria-helminth co-infection is low in two districts in Senegal, possibly due to sustained implementation of effective control measures for malaria and NTDs. These findings could help to develop and implement strategies that would lead to elimination of malaria and helminths in the study areas.
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Affiliation(s)
- Muhammed O. Afolabi
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
- *Correspondence: Muhammed O. Afolabi
| | - Doudou Sow
- Service de Parasitologie-Mycologie, Université Gaston Berger de Saint-Louis, Saint-Louis, Senegal
| | - Ibrahima Mbaye
- Service de Parasitologie-Mycologie, Université de Thies, Thies, Senegal
| | | | - Mor Absa Loum
- Service de Parasitologie-Mycologie, Université Cheikh Anta Diop, Dakar, Senegal
| | | | - Amadou Seck
- Service de Parasitologie-Mycologie, Université de Thies, Thies, Senegal
| | - Isaac A. Manga
- Service de Parasitologie-Mycologie, Université Cheikh Anta Diop, Dakar, Senegal
| | - Cheikh Cissé
- Service de Parasitologie-Mycologie, Université de Thies, Thies, Senegal
| | | | - Awa Diouf
- Service de Parasitologie-Mycologie, Université de Thies, Thies, Senegal
| | - Ndéye Aida Gaye
- Service de Parasitologie-Mycologie, Université de Thies, Thies, Senegal
| | - Aminata Colle Lo
- Service de Parasitologie-Mycologie, Université Cheikh Anta Diop, Dakar, Senegal
| | - Brian Greenwood
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Mahittikorn A, Masangkay FR, De Jesus Milanez G, Kuraeiad S, Kotepui M. Prevalence and effect of Plasmodium spp. and hookworm co-infection on malaria parasite density and haemoglobin level: a meta-analysis. Sci Rep 2022; 12:6864. [PMID: 35477943 PMCID: PMC9046215 DOI: 10.1038/s41598-022-10569-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 04/11/2022] [Indexed: 12/14/2022] Open
Abstract
The dual effects of co-infection of Plasmodium spp. and hookworm on malaria remain under debate. This study investigated prevalence, prevalence odds ratio (POR) of co-infection and impact of co-infection on malaria parasite density and haemoglobin levels in comparison to Plasmodium mono-infection. The protocol for this systematic review and meta-analysis is registered at PROPERO under ID: CRD42020202156. Relevant literatures were obtained from PubMed, ISI Web of Science, and Scopus on 25 December 2020. Mean difference (MD) and confidence interval (CI) of malaria parasite density and haemoglobin were compared using a random effect model. Heterogeneity was assessed using Cochrane Q and I2 statistics. Publication bias was determined by visualising funnel plot asymmetry. Of 1756 articles examined, 22,191 malaria cases across 37 studies included 6096 cases of co-infection of Plasmodium spp. and hookworm. The pooled prevalence was 20% (95% CI 15-26%, I2 99.6%, 37 studies) and was varied in terms of geographical region. Co-infection occurred by chance (OR 0.97, p 0.97, 95% CI 0.73-1.27, I2 95%, 30 studies). The mean malaria parasite density for co-infection (478 cases) was similar to Plasmodium mono-infection (920 cases) (p 0.24, MD 0.86, 95% CI - 0.58-2.29, I2 100%, 7 studies). The mean haemoglobin level for co-infection (90 cases) was similar to Plasmodium mono-infection (415 cases) (p 0.15, MD - 0.63, 95% CI - 1.49-0.23, I2 98%, 4 studies). Co-infection was common and occurred by chance but varied by geographic region. Further studies are required to investigate the mechanism of hookworm infection on malaria severity. Additionally, detection of hookworm infections among patients with malaria in endemic areas of both diseases is recommended to prevent severe malaria.
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Affiliation(s)
- Aongart Mahittikorn
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Giovanni De Jesus Milanez
- Department of Medical Technology, Faculty of Pharmacy, University of Santo Tomas, Manila, Philippines
| | - Saruda Kuraeiad
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand
| | - Manas Kotepui
- Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, Thailand.
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8
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Yoboue CA, Hosch S, Donfack OT, Guirou EA, Nlavo BM, Ayekaba MO, Guerra C, Phiri WP, Garcia GA, Schindler T, Daubenberger CA. Characterising co-infections with Plasmodium spp., Mansonella perstans or Loa loa in asymptomatic children, adults and elderly people living on Bioko Island using nucleic acids extracted from malaria rapid diagnostic tests. PLoS Negl Trop Dis 2022; 16:e0009798. [PMID: 35100277 PMCID: PMC8830708 DOI: 10.1371/journal.pntd.0009798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/10/2022] [Accepted: 01/10/2022] [Indexed: 11/18/2022] Open
Abstract
Background Regular and comprehensive epidemiological surveys of the filarial nematodes Mansonella perstans and Loa loa in children, adolescents and adults living across Bioko Island, Equatorial Guinea are lacking. We aimed to demonstrate that blood retained on malaria rapid diagnostic tests, commonly deployed for malaria surveys, could be used as a source of nucleic acids for molecular based detection of M. perstans and L. loa. We wanted to determine the positivity rate and distribution of filarial nematodes across different age groups and geographical areas as well as to understand level of co-infections with malaria in an asymptomatic population. Methodology M. perstans, L. loa and Plasmodium spp. parasites were monitored by qPCR in a cross-sectional study using DNA extracted from a subset malaria rapid diagnostic tests (mRDTs) collected during the annual malaria indicator survey conducted on Bioko Island in 2018. Principal findings We identified DNA specific for the two filarial nematodes investigated among 8.2% (263) of the 3214 RDTs screened. Positivity rates of M. perstans and L. loa were 6.6% and 1.5%, respectively. M. perstans infection were more prominent in male (10.5%) compared to female (3.9%) survey participants. M. perstans parasite density and positivity rate was higher among older people and the population living in rural areas. The socio-economic status of participants strongly influenced the infection rate with people belonging to the lowest socio-economic quintile more than 3 and 5 times more likely to be L. loa and M. perstans infected, respectively. No increased risk of being co-infected with Plasmodium spp. parasites was observed among the different age groups. Conclusions/Significance We found otherwise asymptomatic individuals were infected with M. perstans and L. loa. Our study demonstrates that employing mRDTs probed with blood for malaria testing represents a promising, future tool to preserve and ship NAs at room temperature to laboratories for molecular, high-throughput diagnosis and genotyping of blood-dwelling nematode filarial infections. Using this approach, asymptomatic populations can be reached and surveyed for infectious diseases beyond malaria. Mansonella perstans and Loa loa are filarial nematodes that infect millions of people living in less developed areas, predominantly in sub-Saharan Africa. Both parasites are neglected among other filarial nematodes because both are regarded as causing mainly asymptomatic infections. The aim of this study was to explore the feasibility of using malaria rapid diagnostic tests (mRDTs) deployed during malaria surveys as a convenient sampling strategy for molecular surveillance of blood-dwelling filarial nematode infections. Our findings demonstrate the potential of mRDTs as a source of parasite DNA beyond malaria, providing an opportunity to expand current knowledge on the distribution and populations mostly affected by M. perstans and L. loa infections to Equatorial Guinea, located in Central-West Africa.
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Affiliation(s)
- Charlene Aya Yoboue
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Salome Hosch
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Etienne A. Guirou
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | | | - Carlos Guerra
- Medical Care Development International, Malabo, Equatorial Guinea
| | - Wonder P. Phiri
- Medical Care Development International, Malabo, Equatorial Guinea
| | | | - Tobias Schindler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail: (TS); (CAD)
| | - Claudia A. Daubenberger
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail: (TS); (CAD)
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9
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Mwamlima TG, Mwakasungula SM, Mkindi CG, Tambwe MM, Mswata SS, Mbwambo SG, Mboya MF, Draper SJ, Silk SE, Mpina MG, Vianney JM, Olotu AI. Understanding the role of serological and clinical data on assessing the dynamic of malaria transmission: a case study of Bagamoyo district, Tanzania. Pan Afr Med J 2022; 43:60. [PMID: 36578806 PMCID: PMC9755714 DOI: 10.11604/pamj.2022.43.60.35779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 09/01/2022] [Indexed: 12/30/2022] Open
Abstract
Introduction naturally acquired blood-stage malaria antibodies and malaria clinical data have been reported to be useful in monitoring malaria change over time and as a marker of malaria exposure. This study assessed the total immunoglobulin G (IgG) levels to Plasmodium falciparum schizont among infants (5-17 months), estimated malaria incidence using routine health facility-based surveillance data and predicted trend relation between anti-schizont antibodies and malaria incidence in Bagamoyo. Methods 252 serum samples were used for assessment of total IgG by enzyme-linked immunosorbent assay and results were expressed in arbitrary units (AU). 147/252 samples were collected in 2021 during a blood-stage malaria vaccine trial [ClinicalTrials.gov NCT04318002], and 105/252 were archived samples of malaria vaccine trial conducted in 2012 [ClinicalTrials.gov NCT00866619]. Malaria incidence was calculated from outpatient clinic data of malaria rapid test or blood smear positive results retrieved from District-Health-Information-Software-2 (DHIS2) between 2013 and 2020. Cross-sectional data from both studies were analysed using STATA version 14. Results this study demonstrated a decline in total anti-schizont IgG levels from 490.21AU in 2012 to 97.07AU in 2021 which was related to a fall in incidence from 58.25 cases/1000 person-year in 2013 to 14.28 cases/1000 person-year in 2020. We also observed a significant difference in incidence when comparing high and low malaria transmission areas and by gender. However, we did not observe differences when comparing total anti-schizont antibodies by gender and study year. Conclusion total anti-schizont antibody levels appear to be an important serological marker of exposure for assessing the dynamic of malaria transmission in infants living in malaria-endemic regions.
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Affiliation(s)
- Tunu Guntram Mwamlima
- Ifakara Health Institute, Bagamoyo, Tanzania
- Department of Life Science and Bio-Engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
- Corresponding author: Tunu Guntram Mwamlima, Ifakara Health Institute, Bagamoyo, Tanzania.
| | | | | | | | | | | | | | - Simon John Draper
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | | | | | - John-Mary Vianney
- Department of Life Science and Bio-Engineering, The Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
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Mwaiswelo RO, Mmbando BP, Chacky F, Molteni F, Mohamed A, Lazaro S, Mkalla SF, Samuel B, Ngasala B. Malaria infection and anemia status in under-five children from Southern Tanzania where seasonal malaria chemoprevention is being implemented. PLoS One 2021; 16:e0260785. [PMID: 34855878 PMCID: PMC8638878 DOI: 10.1371/journal.pone.0260785] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 11/16/2021] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Malaria and anemia remain major public health challenges in Tanzania. Household socioeconomic factors are known to influence these conditions. However, it is not clear how these factors influence malaria transmission and anemia in Masasi and Nanyumbu Districts. This study presents findings on malaria and anemia situation in under-five children and its influencing socioeconomic factors in Masasi and Nanyumbu Districts, surveyed as part of an ongoing seasonal malaria chemoprevention operational study. METHODS A community-based cross-sectional survey was conducted between August and September 2020. Finger-prick blood samples collected from children aged 3-59 months were used to test for malaria infection using malaria rapid diagnostic test (mRDT), thick smears for determination of asexual and sexual parasitemia, and thin smear for parasite speciation. Hemoglobin concentration was measured using a HemoCue spectrophotometer. A structured questionnaire was used to collect household socioeconomic information from parents/caregivers of screened children. The prevalence of malaria was the primary outcome. Chi-square tests, t-tests, and logistic regression models were used appropriately. RESULTS Overall mRDT-based malaria prevalence was 15.9% (373/2340), and was significantly higher in Nanyumbu (23.7% (167/705) than Masasi District (12.6% (206/1635), p<0.001. Location (Nanyumbu), no formal education, household number of people, household number of under-fives, not having a bed net, thatched roof, open/partially open eave, sand/soil floor, and low socioeconomic status were major risks for malaria infection. Some 53.9% (1196/2218) children had anemia, and the majority were in Nanyumbu (63.5% (458/705), p<0.001. Location (Nanyumbu), mRDT positive, not owning a bed net, not sleeping under bed net, open/partially open eave, thatched window, sex of the child, and age of the child were major risk factors for anemia. CONCLUSION Prevalence of malaria and anemia was high and was strongly associated with household socioeconomic factors. Improving household socioeconomic status is expected to reduce the prevalence of the conditions in the area.
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Affiliation(s)
- Richard O. Mwaiswelo
- Department of Microbiology, Immunology and Parasitology, Hubert Kairuki Memorial University, Dar es Salaam, Tanzania
| | - Bruno P. Mmbando
- Tanga Research Centre, National Institute for Medical Research, Tanga, Tanzania
| | - Frank Chacky
- National Malaria Control Programme, Ministry of Health, Community Development, Gender, Elderly and Children, Dodoma, Tanzania
| | - Fabrizio Molteni
- National Malaria Control Programme, Ministry of Health, Community Development, Gender, Elderly and Children, Dodoma, Tanzania
| | - Ally Mohamed
- National Malaria Control Programme, Ministry of Health, Community Development, Gender, Elderly and Children, Dodoma, Tanzania
| | - Samwel Lazaro
- National Malaria Control Programme, Ministry of Health, Community Development, Gender, Elderly and Children, Dodoma, Tanzania
| | - Sylvia F. Mkalla
- Directorate of Research, Coordination, and Promotion, Tanzania Commission for Science and Technology, Dar es Salaam, Tanzania
| | - Bushukatale Samuel
- Department of Medical Parasitology and Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Billy Ngasala
- Department of Medical Parasitology and Entomology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
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11
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Eltantawy M, Orsel K, Schroeder A, Morona D, Mazigo HD, Kutz S, Hatfield J, Manyama M, van der Meer F. Soil transmitted helminth infection in primary school children varies with ecozone in the Ngorongoro Conservation Area, Tanzania. Trop Med Health 2021; 49:22. [PMID: 33691800 PMCID: PMC7945338 DOI: 10.1186/s41182-021-00310-6] [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: 09/22/2020] [Accepted: 02/22/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Soil-transmitted helminthiasis is a neglected tropical disease, thriving in environments of poverty and disadvantage. Our objective was to determine the prevalence and intensity of four soil transmitted helminths (STH) among primary school children in the Ngorongoro Conservation Area (NCA), Tanzania. METHODS A cross-sectional study was performed between May 15th and June 2nd, 2014. Six of 20 primary schools were chosen, based on elevation, designated low elevation ecozone (LEE) or high elevation ecozone (HEE). A total of 340 children from standards one to four were recruited. Height and weight of each child was determined and body mass index (BMI) was calculated. Stool samples were analyzed using the Kato-Katz, Wisconsin, and Baermann techniques to detect STH eggs and larvae. An interviewer-administered questionnaire on socio-demographic variables was used to capture information from the school's headmaster and a checklist was used to assess sanitation facilities. RESULTS STHs identified included Ascaris (presumably lumbricoides), Trichuris (presumably trichiura), hookworms (presumably Ancylostoma duodenale and/or Necator americanus), and Strongyloides (presumably stercoralis). The overall prevalence of STH infection was 29.0% in LEE and 34.0% in HEE. Prevalence was 34.3% and 28.2% in males versus females, respectively. Ascaris sp. were only identified in HEE, prevalence of Trichuris sp. and hookworms were significantly higher in HEE compared to LEE, and Strongyloides spp. prevalence was lower in HEE. Intensity of Trichuris sp. was significantly higher in HEE and lower for hookworms. We did not detect a significant relationship between BMI and helminth intensity; however, BMI was lower in lower elevations and in males vs. females. Sanitation practices are taught at the schools, but challenges were identified when implementing. Latrine facilities were available and latrine-cleaning routines were practiced; however, hand washing practices were challenging due to restricted water availability. CONCLUSIONS Significant differences in prevalence in HEE and LEE exist, and STH infections are still very common among school children suggesting that anthelminthic intervention and education may be necessary in this region. Based on this outcome, the study area in the NCA would be classified as a medium risk area, where periodic treatment recommendations should be based on prevalence estimations in the different ecozones. TRIAL REGISTRATION Ethics approval was obtained from the Catholic University of Health and Allied Sciences (CUHAS; Lake Zone Institutional Review Board MR/53/100/307)); the Conjoint Health Research Ethics Board (CHREB) at the University of Calgary in Canada (Study ID REB14-0127); the National Institute of Medical Research (NIMR) of Tanzania; and the Tanzania Commission for Science and Technology (COSTEC).
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Affiliation(s)
- Manar Eltantawy
- Department. of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Karin Orsel
- Department. of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.,Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Ashley Schroeder
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Domenica Morona
- Department of Parasitology, Catholic University of Health and Allied Science, Mwanza, Tanzania
| | - Humphrey D Mazigo
- Department of Parasitology, Catholic University of Health and Allied Science, Mwanza, Tanzania
| | - Susan Kutz
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Jennifer Hatfield
- Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Mange Manyama
- Division of Medical Education, Weill Cornell Medicine - Qatar, Doha, Qatar
| | - Frank van der Meer
- Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. .,Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
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12
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Afolabi MO, Ale BM, Dabira ED, Agbla SC, Bustinduy AL, Ndiaye JLA, Greenwood B. Malaria and helminth co-infections in children living in endemic countries: A systematic review with meta-analysis. PLoS Negl Trop Dis 2021; 15:e0009138. [PMID: 33600494 PMCID: PMC7924789 DOI: 10.1371/journal.pntd.0009138] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 03/02/2021] [Accepted: 01/13/2021] [Indexed: 12/03/2022] Open
Abstract
Background Current knowledge on the burden of, and interactions between malaria and helminth co-infections, as well as the impact of the dual infections on anaemia, remains inconclusive. We have conducted a systematic review with meta-analysis to update current knowledge as a first step towards developing and deploying coordinated approaches to the control and, ultimately, elimination of malaria-helminth co-infections among children living in endemic countries. Methodology/Principal findings We searched Medline, Embase, Global Health and Web of Science from each database inception until 16 March 2020, for peer-reviewed articles reporting malaria-helminth co-infections in children living in endemic countries. No language restriction was applied. Following removal of duplicates, two reviewers independently screened the studies for eligibility. We used the summary odds ratio (OR) and 95% confidence intervals (CI) as a measure of association (random-effects model). We also performed Chi-square heterogeneity test based on Cochrane’s Q and evaluated the severity of heterogeneity using I2 statistics. The included studies were examined for publication bias using a funnel plot and statistical significance was assessed using Egger’s test (bias if p<0.1). Fifty-five of the 3,507 citations screened were eligible, 28 of which had sufficient data for meta-analysis. The 28 studies enrolled 22, 114 children in 13 countries across sub-Saharan Africa, Southeast Asia and South America. Overall, the pooled estimates showed a prevalence of Plasmodium-helminth co-infections of 17.7% (95% CI 12.7–23.2%). Summary estimates from 14 studies showed a lower odds of P. falciparum infection in children co-infected with Schistosoma spp (OR: 0.65; 95%CI: 0.37–1.16). Similar lower odds of P. falciparum infection were observed from the summary estimates of 24 studies in children co-infected with soil transmitted helminths (STH) (OR: 0.42; 95%CI: 0.28–0.64). When adjusted for age, gender, socio-economic status, nutritional status and geographic location of the children, the risk of P. falciparum infection in children co-infected with STH was higher compared with children who did not have STH infection (OR = 1.3; 95% CI 1.03–1.65). A subset of 16 studies showed that the odds of anaemia were higher in children co-infected with Plasmodium and STH than in children with Plasmodium infection alone (OR = 1.20; 95% CI: 0.59–2.45), and were almost equal in children co-infected with Plasmodium-Schistosoma spp or Plasmodium infection alone (OR = 0.97, 95% CI: 0.30–3.14). Conclusions/Significance The current review suggests that prevalence of malaria-helminth co-infection is high in children living in endemic countries. The nature of the interactions between malaria and helminth infection and the impact of the co-infection on anaemia remain inconclusive and may be modulated by the immune responses of the affected children. Updated evidence is needed to guide the planning and implementation of appropriate interventions for control of mixed infections involving malaria and worms affecting children living in endemic countries. We performed a systematic review and meta-analysis to update current knowledge on the magnitude of the burden of dual infections with malaria and worms in children in the developing world. We searched all published articles available in Medline, Embase, Global Health and Web of Science from the database inception until 16 March 2020, without any language restriction. We found 55 eligible studies, and 28 of these studies were included in the meta-analysis. A summary of the evidence synthesis showed that the burden of dual infections involving malaria and worm parasites is high in children and varies significantly across endemic countries. There was a lower risk of P. falciparum infection in children infected with soil transmitted helminths (STH) or S. haematobium or S.mansoni. Conversely, the odds of anaemia were higher in children who had dual infections with Plasmodium and STH parasites than in children with a Plasmodium infection alone while the odds of anaemia were almost equal in children who were co-infected with Plasmodium-Schistosoma compared to those with a Plasmodium infection alone. These findings underscore the need to further understand the epidemiology of malaria-helminth co-infections in order to support implementation of appropriate interventions for control and, ultimately, elimination of the dual infections in children living in endemic countries, especially low and middle-income countries (LMIC).
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Affiliation(s)
- Muhammed O. Afolabi
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
- * E-mail:
| | | | - Edgard D. Dabira
- Disease Control and Elimination Theme, Medical Research Council Unit The Gambia at London School of Hygiene & Tropical Medicine, Fajara, The Gambia
| | - Schadrac C. Agbla
- Department of Health Data Science, University of Liverpool, Liverpool, United Kingdom
| | - Amaya L. Bustinduy
- Department of Clinical Research, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Jean Louis A. Ndiaye
- Department of Parasitology, University of Thies, Thies, Senegal
- Département de Parasitologie-Mycologie, Université Cheikh Anta Diop, Dakar, Senegal
| | - Brian Greenwood
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
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13
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Yang D, He Y, Wu B, Deng Y, Li M, Yang Q, Huang L, Cao Y, Liu Y. Drinking water and sanitation conditions are associated with the risk of malaria among children under five years old in sub-Saharan Africa: A logistic regression model analysis of national survey data. J Adv Res 2020; 21:1-13. [PMID: 31641533 PMCID: PMC6796660 DOI: 10.1016/j.jare.2019.09.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 01/10/2023] Open
Abstract
Current efforts for the prevention of malaria have resulted in notable reductions in the global malaria burden; however, they are not enough. Good hygiene is universally considered one of the most efficacious and straightforward measures to prevent disease transmission. This work analyzed whether improved drinking water and sanitation (WS) conditions were associated with a decreased risk of malaria infection. Data were acquired through surveys published between 2006 and 2018 from the Demographic and Health Program in sub-Saharan Africa (SSA). Multiple logistic regression was used for each national survey to identify the associations between WS conditions and malaria infection diagnosed by microscopy or a malaria rapid diagnostic test (RDT) among children (0-59 months), with adjustments for age, gender, indoor residual spraying (IRS), insecticide-treated net (ITN) use, house quality, and the mother's highest educational level. Individual nationally representative survey odds ratios (ORs) were combined to obtain a summary OR using a random-effects meta-analysis. Among the 247,440 included children, 18.8% and 24.2% were positive for malaria infection based on microscopy and RDT results, respectively. Across all surveys, both unprotected water and no facility users were associated with increased malaria risks (unprotected water: aOR 1.17, 95% CI 1.07-1.27, P = 0.001; no facilities: aOR 1.35, 95% CI 1.24-1.47, P < 0.001; respectively), according to microscopy, whereas the odds of malaria infection were 48% and 49% less among piped water and flush-toilet users, respectively (piped water: aOR 0.52, 95% CI 0.45-0.59, P < 0.001; flush toilets: aOR 0.51, 95% CI 0.43-0.61, P < 0.001). The trends of individuals diagnosed by RDT were consistent with those of individuals diagnosed by microscopy. Risk associations were more pronounced among children with a "nonpoor" socioeconomic status who were unprotected water or no facility users. WS conditions are a vital risk factor for malarial infection among children (0-59 months) across SSA. Improved WS conditions should be considered a potential intervention for the prevention of malaria in the long term.
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Key Words
- 95% CI, 95% confidence interval
- Children
- DHS, Demographic and Health Survey
- Drinking water
- IRS, indoor residual spraying
- ITNs, insecticide treated nets
- LLINs, long-lasting insecticidal mosquito nets
- MIS, Malaria Indicator Surveys
- Malaria
- NTDs, neglected tropical diseases
- RDT, rapid diagnostic test
- Risk
- SDGs, sustainable development goals
- SSA, sub-Saharan Africa
- STHs, soil transmitted helminth diseases
- Sanitation
- Sub-Saharan Africa
- WASH, water, sanitation, and hygiene
- WHO, World Health Organization
- WS, drinking water and sanitation
- aOR, adjusted odds ratio
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Affiliation(s)
- Dan Yang
- Department of Environmental Health, School of Public Health, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
| | - Yang He
- Department of Central Laboratory, The First Affiliated Hospital, China Medical University, 155th, Nanjing North Street, Shenyang, 110001 Liaoning, China
| | - Bo Wu
- Department of Anus & Intestine Surgery, The First Affiliated Hospital, China Medical University, 155th, Nanjing North Street, Shenyang, 110001 Liaoning, China
| | - Yan Deng
- Department of Environmental Health, School of Public Health, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
| | - Menglin Li
- Department of Environmental Health, School of Public Health, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
| | - Qian Yang
- Department of Environmental Health, School of Public Health, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
| | - Liting Huang
- Department of Environmental Health, School of Public Health, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
| | - Yaming Cao
- Department of Immunology, College of Basic Medical Science, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
| | - Yang Liu
- Department of Environmental Health, School of Public Health, China Medical University, 77th, Puhe Road, Shenyang, 110122 Liaoning, China
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Malaria Parasitemia in Febrile Patients Mono- and Coinfected with Soil-Transmitted Helminthiasis Attending Sanja Hospital, Northwest Ethiopia. J Parasitol Res 2020; 2020:9891870. [PMID: 32089868 PMCID: PMC7024094 DOI: 10.1155/2020/9891870] [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] [Received: 08/02/2019] [Revised: 11/20/2019] [Accepted: 01/13/2020] [Indexed: 11/18/2022] Open
Abstract
Background Malaria is a life-threatening disease associated with high morbidity and mortality. Helminths are among the most widespread infectious agents prevalent in tropical and subtropical regions of the developing world. Malaria and soil-transmitted helminthiasis (STHs) are coendemic and major public health problems in Ethiopia. The effects of helminth coinfection on malaria parasitemia remained poorly understood. Therefore, the objective of this study was to assess malaria parasitemia among malaria-monoinfected and malaria-soil-transmitted helminthiasis-coinfected febrile patients attending Sanja Hospital, Northwest Ethiopia. Methods A cross-sectional study with parallel groups was conducted to assess malaria parasitemia among malaria-monoinfected and malaria-soil-transmitted helminthiasis-coinfected febrile patients in Sanja Hospital from January to March 2019. Double population proportion formula was used for sample size calculation, and convenient sampling technique was used to select 134 study participants. Data were entered and analyzed by using the Statistical Package for Social Sciences (SPSS) version 20. Descriptive statistics, independent t-test, and one-way analysis of variance (ANOVA) were performed. A P value of <0.05 was considered as statistically significant. Results From 134 malaria-positive study participants, 67 were malaria-monoinfected and 67 were malaria-STHs-coinfected patients. Out of 67 malaria STHs-coinfected patients, 54 (80.6%) were infected with hookworm followed by Ascaris lumbricoides 11 (16.4%) and Strongyloides stercoralis 2 (3%). The mean Plasmodium parasite density was significantly higher in malaria-STHs-coinfected patients than in patients infected with only Plasmodium parasite density was significantly higher in malaria-STHs-coinfected patients than in patients infected with only P value of <0.05 was considered as statistically significant. Plasmodium parasite density was significantly higher in malaria-STHs-coinfected patients than in patients infected with only F = 6.953, P value of <0.05 was considered as statistically significant. Conclusions Infections with STHs, especially hookworm, were positively associated with Plasmodium parasite density. The current study finding also revealed that increased worm burden of hookworm as expressed by egg intensity had significantly increased Plasmodium parasite density.Plasmodium parasite density was significantly higher in malaria-STHs-coinfected patients than in patients infected with only Plasmodium parasite density was significantly higher in malaria-STHs-coinfected patients than in patients infected with only.
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Amoani B, Adu B, Frempong MT, Sarkodie-Addo T, Victor Nuvor S, Abu EK, Harrison LM, Cappello M, Gyan B, Wilson MD. Cytokine profiles of Necator americanus and Plasmodium falciparum co-infected patients in rural Ghana. Cytokine X 2019; 1:100014. [PMID: 33604551 PMCID: PMC7885886 DOI: 10.1016/j.cytox.2019.100014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 08/21/2019] [Accepted: 08/28/2019] [Indexed: 12/20/2022] Open
Abstract
Co-infection of hookworm with P. falciparum modulates blood parasitemia levels. Cytokine levels were higher in the parasite infected individuals. Serum eotaxin level correlate negatively with hookworm intensity. Deworming drug treatment alters cytokine profiles in hookworm infected subjects.
Background Necator americanus (hookworm) and Plasmodium falciparum co-infections are common in endemic communities in rural Ghana. Human immune responses to P. falciparum and hookworm are complex, and the dynamics of cytokine levels and effector mediators are poorly understood. This study aimed to determine the effect of hookworm and P. falciparum co-infection on parasite intensities and cytokine profiles in individuals before and after deworming drug treatment. Methods In this cross-sectional study conducted in the Kintampo North Municipality of Ghana blood and stool samples were analyzed from 984 participants (aged 4–88 years). Stool samples were collected at baseline from all participants and examined for the presence of hookworm using the Kato-Katz method. Blood and stool samples were analysed again two weeks after albendazole treatment of hookworm infected individuals. Malaria parasitaemia was estimated by light microscopy and P. falciparum-specific 18S rRNA gene PCR method used for species identification. Serum levels of circulating cytokines interleukins -5, -10 (IL-5, IL-10), tumor necrosis factor [TNF]-α, and eotaxin [CCL11] were determined using ELISA based methods. Results Malaria parasitaemia was significantly reduced in hookworm and P. falciparum co-infected individuals (p = 0.0018) while hookworm intensity was similar between groups. IL-10 level was significantly higher in the co-infected individuals (39.9 ± 12.2 pg/ml) compared to the single infected or the uninfected group (10.7 ± 7.6 mg/ml). IL-5 level was higher in the hookworm only infected individual. TNF-α levels were higher in all infected groups compared to the uninfected controls. CCL11 levels were significantly higher in subjects infected with hookworm only or co-infected with hookworm and P. falciparum. There was a significantly negative correlation (rs = −0.39, p = 0.021) between hookworm eggs per gram of stool and CCL11 levels in the group mono-infected with hookworm which was not affected by treatment. Treatment with albendazole led to a significant reduction of TNF-α (p = 0.041), IL-5 (p = 0.01) and IL-10 (p = 0.001) levels. Conclusion This study shows that in the absence of other helminths, co-infection of hookworm with P. falciparum may modulate blood parasitemia levels and cytokine responses. Data also show that deworming drug treatment alters these cytokine profiles in hookworm infected subjects. Future studies to elucidate the potential mechanisms underlying these observations should include an assessment of parasite specific cellular responses.
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Affiliation(s)
- Benjamin Amoani
- Department of Biomedical Science, College of Health Sciences, University of Cape Coast, Cape Coast, Ghana.,Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana.,Molecular Medicine Department, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Ghana
| | - Bright Adu
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Margaret T Frempong
- Molecular Medicine Department, School of Medical Sciences, Kwame Nkrumah University of Science and Technology, Ghana
| | - Tracy Sarkodie-Addo
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Samuel Victor Nuvor
- Department of Microbiology, College of Health Sciences, University of Cape Coast, Cape Coast, Ghana
| | - Emmanuel Kwasi Abu
- Department of Optometry, College of Health Sciences, University of Cape Coast, Cape Coast, Ghana
| | - Lisa M Harrison
- Partnerships for Global Health, Department of Pediatrics, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Michael Cappello
- Partnerships for Global Health, Department of Pediatrics, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Ben Gyan
- Department of Immunology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
| | - Michael D Wilson
- Parasitology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana
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Sacolo-Gwebu H, Kabuyaya M, Chimbari M. Knowledge, attitudes and practices on schistosomiasis and soil-transmitted helminths among caregivers in Ingwavuma area in uMkhanyakude district, South Africa. BMC Infect Dis 2019; 19:734. [PMID: 31438865 PMCID: PMC6704662 DOI: 10.1186/s12879-019-4253-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 07/03/2019] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Schistosomiasis and soil-transmitted helminth infections are among the most chronic infections worldwide. Based on their demonstrable impact on human health, the WHO recently recommended the implementation of robust strategies aimed at controlling or eliminating schistosomiasis and soil-transmitted helminths by 2020. The implementation of this strategy, however, warrants a clear understanding of the community's knowledge, attitudes and practices in relation to these infections. This study sought to identify sociocultural gaps that should be addressed to ensure the success of cost-effective community-based schistosomiasis-soil-transmitted helminths control and elimination programs. METHODS This was a cross-sectional mixed methodology study. Quantitative data were collected using a structured questionnaire from 442 caregivers of preschool aged children. In-depth interviews and focus group discussions were conducted among caregivers, preschool teachers, traditional authorities and community caregivers. All interviews were captured using an audio recorder to maximize accuracy. Quantitative data were analysed using bivariate and multivariate techniques while qualitative data were analysed thematically. RESULTS Findings reflected inadequate knowledge, attitudes and practices in relation to schistosomiasis and soil-transmitted helminths while awareness of schistosomiasis and soil-transmitted helminths was high (87.1 and 79.2% respectively). Correct knowledge on transmission, prevention, signs and symptoms and life cycle was low (below 50%) for both infections among those who had heard of the disease. From multivariate analysis, being aged at least 35 years increased the odds of reporting good practices on schistosomiasis by 65% (COR 1.652, 95% CI: 1.073-2.543) while receiving health information through community meetings (COR 0.072, 95% CI: 0.010-0.548) significantly reduced the odds of having good knowledge on schistosomiasis. CONCLUSIONS These findings are valuable in designing behavioural change approaches towards enhancing health outcomes through community-based interventions to ensure effective control and elimination of schistosomiasis and soil-transmitted helminths. There is a critical need for channelling efforts towards making health education the core of schistosomiasis and soil-transmitted helminths programs aimed at achieving intensified control or elimination of these infections by 2020.
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Affiliation(s)
- Hlengiwe Sacolo-Gwebu
- School of Nursing and Public Health, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Muhubiri Kabuyaya
- School of Nursing and Public Health, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Moses Chimbari
- School of Nursing and Public Health, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
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Donohue RE, Cross ZK, Michael E. The extent, nature, and pathogenic consequences of helminth polyparasitism in humans: A meta-analysis. PLoS Negl Trop Dis 2019; 13:e0007455. [PMID: 31211774 PMCID: PMC6599140 DOI: 10.1371/journal.pntd.0007455] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/28/2019] [Accepted: 05/09/2019] [Indexed: 02/07/2023] Open
Abstract
Background Individual helminth infections are ubiquitous in the tropics; geographical overlaps in endemicity and epidemiological reports suggest areas endemic for multiple helminthiases are also burdened with high prevalences of intestinal protozoan infections, malaria, tuberculosis (TB), and human immunodeficiency virus (HIV). Despite this, pathogens tend to be studied in isolation, and there remains a need for a better understanding of the community ecology and health consequences of helminth polyparasitism to inform the design of effective parasite control programs. Methodology We performed meta-analyses to (i) evaluate the commonality of polyparasitism for helminth-helminth, helminth-intestinal protozoa, helminth-malaria, helminth-TB, and helminth-HIV co-infections, (ii) assess the potential for interspecies interactions among helminth-helminth and helminth-intestinal protozoan infections, and (iii) determine the presence and magnitude of association between specific parasite pairs. Additionally, we conducted a review of reported health consequences of multiply-infected individuals compared to singly- or not multiply-infected individuals. Principal findings We found that helminth-helminth and helminth-intestinal protozoan multiple infections were significantly more common than single infections, while individuals with malaria, TB, and HIV were more likely to be singly-infected with these infections than co-infected with at least one helminth. Most observed species density distributions significantly differed from the expected distributions, suggesting the potential presence of interspecies interactions. All significant associations between parasite pairs were positive in direction, irrespective of the combination of pathogens. Polyparasitized individuals largely exhibited lower hemoglobin levels and higher anemia prevalence, while the differences in growth-related variables were mostly statistically insignificant. Conclusions Our findings confirm that helminth polyparasitism and co-infection with major diseases is common in the tropics. A multitude of factors acting at various hierarchical levels, such as interspecies interactions at the within-host infra-parasite community level and environmental variables at the higher host community level, could explain the observed positive associations between pathogens; there remains a need to develop new frameworks which can consider these multilevel factors to better understand the processes structuring parasite communities to accomplish their control. Helminth infections are a highly prevalent global health problem. These parasitic worm infections occur in areas also burdened with intestinal protozoan infections, malaria, tuberculosis, and human immunodeficiency virus. While these pathogens tend to be studied in isolation, there remains a need to better understand the nature, extent, and health consequences of helminth polyparasitism and co-infection with major diseases. Here, we reviewed the literature and performed meta-analyses to evaluate the commonality of helminth polyparasitism and co-infection, the potential for interspecies interactions between parasites, the association between parasite pairs, and the health consequences among multiply-infected individuals. We confirmed that polyparasitism and co-infection with major diseases are common in the global South and found that multiply-infected individuals experienced worse health consequences when compared to singly or not-multiply infected individuals. Our analysis suggested the potential presence of interspecies interactions and we identified the existence of positive associations between parasite pairs. These findings support the call for integrating deworming into malaria, TB, and HIV treatment protocols and suggest there remains a need to improve our understanding of the factors influencing co-transmission to achieve sustainable parasite control.
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Affiliation(s)
- Rose E. Donohue
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Zoë K. Cross
- University of Utah, Salt Lake City, Utah, United States of America
| | - Edwin Michael
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, United States of America
- * E-mail:
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M’bondoukwé NP, Kendjo E, Mawili-Mboumba DP, Koumba Lengongo JV, Offouga Mbouoronde C, Nkoghe D, Touré F, Bouyou-Akotet MK. Prevalence of and risk factors for malaria, filariasis, and intestinal parasites as single infections or co-infections in different settlements of Gabon, Central Africa. Infect Dis Poverty 2018; 7:6. [PMID: 29378644 PMCID: PMC5789590 DOI: 10.1186/s40249-017-0381-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 12/13/2017] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Malaria, filariasis, and intestinal parasitic infections (IPIs) are common and frequently overlap in developing countries. The prevalence and predictors of these infections were investigated in three different settlements (rural, semi-urban, and urban) of Gabon. METHODS During cross-sectional surveys performed from September 2013 to June 2014, 451 individuals were interviewed. In addition, blood and stool samples were analysed for the presence of Plasmodium, filarial roundworm, intestinal protozoan, and helminth infections. RESULTS Intestinal parasitic infections (61.1%), including intestinal protozoa (56.7%) and soil-transmitted helminths (STHs) (22.2%), predominated, whereas Plasmodium falciparum (18.8%), Loa loa (4.7%), and Mansonella perstans (1.1%) were less prevalent. Filariasis and STHs were mainly found in rural settlements, whereas a higher plasmodial infection prevalence rate was observed in the periurban area. The most common IPI was blastocystosis (48.6%), followed by ascaridiasis (13.7%), trichuriasis (11.8%), amoebiasis (9.3%), giardiasis (4.8%), and strongyloidiasis (3.7%). Hookworm was detected in one adult from rural Dienga. Adults had a higher prevalence of Blastocystis hominis and STHs, whereas Giardia duodenalis was more frequently observed among children aged below 5 years (P < 0.01). The polyparasitism rate was 41.5%, with 7.0% Plasmodium-IPIs and 1.8% Plasmodium-STH co-infections. The multivariate analysis showed that living in a suburban area, belonging to the age group of 5-15 years, having none or a secondary education, or having an open body water close to home were significant risk factors for malaria (P ≤ 0.01). For STH infections, identified risk factors were drinking untreated water and living in a rural area (P ≤ 0.04). No significant predictors were identified for IPIs and malaria-IPI co-infection. CONCLUSIONS This study reports a high prevalence of IPIs and intestinal protozoa, but a low rate of malaria-IPI co-infections in the study sites. Improvements in the living conditions of the population such as adequate water supply and proper health education and sanitation should be integrated into control strategies for malaria, STHs, and IPIs.
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Affiliation(s)
- Noé Patrick M’bondoukwé
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, P.O. Box 4009, Libreville, Gabon
| | - Eric Kendjo
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, P.O. Box 4009, Libreville, Gabon
| | - Denise Patricia Mawili-Mboumba
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, P.O. Box 4009, Libreville, Gabon
| | - Jeanne Vanessa Koumba Lengongo
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, P.O. Box 4009, Libreville, Gabon
| | - Christelle Offouga Mbouoronde
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, P.O. Box 4009, Libreville, Gabon
| | - Dieudonné Nkoghe
- International Center for Medical Research of Franceville, Franceville, Gabon
| | - Fousseyni Touré
- International Center for Medical Research of Franceville, Franceville, Gabon
| | - Marielle Karine Bouyou-Akotet
- Department of Parasitology-Mycology, Faculty of Medicine, University of Health Sciences, P.O. Box 4009, Libreville, Gabon
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Menezes RADO, Gomes MDSM, Mendes AM, Couto ÁARDA, Nacher M, Pimenta TS, de Sousa ACP, Baptista ARDS, de Jesus MI, Enk MJ, Cunha MG, Machado RLD. Enteroparasite and vivax malaria co-infection on the Brazil-French Guiana border: Epidemiological, haematological and immunological aspects. PLoS One 2018; 13:e0189958. [PMID: 29293589 PMCID: PMC5749708 DOI: 10.1371/journal.pone.0189958] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 12/05/2017] [Indexed: 11/30/2022] Open
Abstract
Malaria-enteroparasitic co-infections are known for their endemicity. Although they are prevalent, little is known about their epidemiology and effect on the immune response. This study evaluated the effect of enteroparasite co-infections with malaria caused by Plasmodium vivax in a border area between Brazil and French Guiana. The cross sectional study took place in Oiapoque, a municipality of Amapá, on the Amazon border. Malaria was diagnosed using thick blood smears, haemoglobin dosage by an automated method and coproparasitology by the Hoffman and Faust methods. The anti-PvMSP-119 IgG antibodies in the plasma were evaluated using ELISA and Th1 (IFN-γ, TNF-α and IL-2), and Th2 (IL-4, IL-5 and IL-10) cytokine counts were performed by flow cytometry. The participants were grouped into those that were monoinfected with vivax malaria (M), vivax malaria-enteroparasite co-infected (CI), monoinfected with enteroparasite (E) and endemic controls (EC), who were negative for both diseases. 441 individuals were included and grouped according to their infection status: [M 6.9% (30/441)], [Cl 26.5% (117/441)], [E 32.4% (143/441)] and [EC 34.2% (151/441)]. Males prevailed among the (M) 77% (23/30) and (CI) 60% (70/117) groups. There was a difference in haemoglobin levels among the different groups under study for [EC-E], [EC-Cl], [E-M] and [Cl-M], with (p < 0.01). Anaemia was expressed as a percentage between individuals [CI-EC (p < 0.05)]. In terms of parasitaemia, there were differences for the groups [CI-M (p < 0.05)]. Anti-PvMSP-119 antibodies were detected in 51.2% (226/441) of the population. The level of cytokines evaluation revealed a large variation in TNF-α and IL-10 concentrations in the co-infected group. In this study we did not observe any influence of coinfection on the acquisition of IgG antibodies against PvMSP119, as well as on the profile of the cytokines that characterize the Th1 and Th2 patterns. However, co-infection increased TNF-α and IL-10 levels.
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Affiliation(s)
- Rubens Alex de Oliveira Menezes
- Postgraduate Program in the Biology of Infectious and Parasitic Agents, Federal University of Pará (UFPA), Belém, Pará State, Brazil
- Laboratory of morphofunctional and parasitic studies with impact on health (LEMPIS), Federal University of Amapá (UNIFAP), Macapa, Amapá State, Brazil
- * E-mail:
| | | | - Anapaula Martins Mendes
- UNIFAP/Oiapoque Binational Campus, Federal University of Amapá, Oiapoque, Amapá State, Brazil
| | | | - Mathieu Nacher
- Centre d’Investigation Clinique, CIC INSERM 1424, Centre Hospitalier de Cayenne, Cayenne, French Guiana
| | - Tamirys Simão Pimenta
- Postgraduate Program in Neuroscience and Cell Biology, UFPA, Belém, Pará State, Brazil
- Evandro Chagas Institute/Brazilian Secretariat of Health Surveillance (SVS)/Brazilian Ministry of Health (MS), Ananindeua, Pará State, Brazil
| | - Aline Collares Pinheiro de Sousa
- Evandro Chagas Institute/Brazilian Secretariat of Health Surveillance (SVS)/Brazilian Ministry of Health (MS), Ananindeua, Pará State, Brazil
| | | | - Maria Izabel de Jesus
- Evandro Chagas Institute/Brazilian Secretariat of Health Surveillance (SVS)/Brazilian Ministry of Health (MS), Ananindeua, Pará State, Brazil
| | - Martin Johannes Enk
- Evandro Chagas Institute/Brazilian Secretariat of Health Surveillance (SVS)/Brazilian Ministry of Health (MS), Ananindeua, Pará State, Brazil
| | - Maristela Gomes Cunha
- Postgraduate Program in the Biology of Infectious and Parasitic Agents, Federal University of Pará (UFPA), Belém, Pará State, Brazil
- Laboratory of Microbiology and Immunology, Federal University of Pará (UFPA), Belém, Pará State, Brazil
| | - Ricardo Luiz Dantas Machado
- Postgraduate Program in the Biology of Infectious and Parasitic Agents, Federal University of Pará (UFPA), Belém, Pará State, Brazil
- Evandro Chagas Institute/Brazilian Secretariat of Health Surveillance (SVS)/Brazilian Ministry of Health (MS), Ananindeua, Pará State, Brazil
- Fluminense Federal University, Niterói, Rio de Janeiro State, Brazil
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Prevalence and clinical relevance of helminth co-infections among tuberculosis patients in urban Tanzania. PLoS Negl Trop Dis 2017; 11:e0005342. [PMID: 28178325 PMCID: PMC5319816 DOI: 10.1371/journal.pntd.0005342] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 02/21/2017] [Accepted: 01/20/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Helminth infections can negatively affect the immunologic host control, which may increase the risk of progression from latent Mycobacterium tuberculosis infection to tuberculosis (TB) disease and alter the clinical presentation of TB. We assessed the prevalence and determined the clinical relevance of helminth co-infection among TB patients and household contact controls in urban Tanzania. METHODOLOGY Between November 2013 and October 2015, we enrolled adult (≥18 years) sputum smear-positive TB patients and household contact controls without TB during an ongoing TB cohort study in Dar es Salaam, Tanzania. We used Baermann, FLOTAC, Kato-Katz, point-of-care circulating cathodic antigen, and urine filtration to diagnose helminth infections. Multivariable logistic regression models with and without random effects for households were used to assess for associations between helminth infection and TB. PRINCIPAL FINDINGS A total of 597 TB patients and 375 household contact controls were included. The median age was 33 years and 60.2% (585/972) were men. The prevalence of any helminth infection among TB patients was 31.8% (190/597) and 25.9% (97/375) among controls. Strongyloides stercoralis was the predominant helminth species (16.6%, 161), followed by hookworm (9.0%, 87) and Schistosoma mansoni (5.7%, 55). An infection with any helminth was not associated with TB (adjusted odds ratio (aOR) 1.26, 95% confidence interval (CI): 0.88-1.80, p = 0.22), but S. mansoni infection was (aOR 2.15, 95% CI: 1.03-4.45, p = 0.040). Moreover, S. mansoni infection was associated with lower sputum bacterial load (aOR 2.63, 95% CI: 1.38-5.26, p = 0.004) and tended to have fewer lung cavitations (aOR 0.41, 95% CI: 0.12-1.16, p = 0.088). CONCLUSIONS/SIGNIFICANCE S. mansoni infection was an independent risk factor for active TB and altered the clinical presentation in TB patients. These findings suggest a role for schistosomiasis in modulating the pathogenesis of human TB. Treatment of helminths should be considered in clinical management of TB and TB control programs.
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Epidemiology of Plasmodium and Helminth Coinfection and Possible Reasons for Heterogeneity. BIOMED RESEARCH INTERNATIONAL 2016; 2016:3083568. [PMID: 27092310 PMCID: PMC4820611 DOI: 10.1155/2016/3083568] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 03/05/2016] [Accepted: 03/08/2016] [Indexed: 12/27/2022]
Abstract
Understanding the impact of helminth infections on clinical malaria is useful for designing effective malaria control strategies. Plenty of epidemiological studies have been conducted to unravel the nature of interactions between Plasmodium and helminth infection. Careful broad summarization of the existing literature suggests that Schistosoma mansoni and hookworm infections may increase the risk of clinical malaria and associated morbidities, but Trichuris trichiura infection is not associated with the occurrence of clinical malaria and related outcomes. However, findings about effect of Ascaris lumbricoides and Schistosoma haematobium infection on clinical malaria are contradictory. Furthermore, the nature of relationship of helminth infection with severe malaria has also not been determined with certainty. This review summarizes the findings of epidemiological studies of Plasmodium and helminth coinfection, placing greater emphasis on the impact of the coinfection on malaria. Possible reasons for the heterogeneity of the findings on malaria and helminth coinfections are also discussed.
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Abstract
Soil-transmitted helminths (STHs) infect over one billion people worldwide. Ascariasis may mimic a number of conditions, and individual clinical diagnosis often requires a thorough work-up. Kato-Katz thick smears are the standard detection method for Ascaris and, despite low sensitivity, are often used for mapping and monitoring and evaluation of national control programmes. Although increased sampling (number of stools) and diagnostic (number of examinations per stool) efforts can improve sensitivity, Kato-Katz is less sensitive than other microscopy methods such as FLOTAC®. Antibody-based diagnostics may be a sensitive diagnostic tool; however, their usefulness is limited to assessing transmission in areas aiming for elimination. Molecular diagnostics are highly sensitive and specific, but high costs limit their use to individual diagnosis, drug - efficacy studies and identification of Ascaris suum. Increased investments in research on Ascaris and other STHs are urgently required for the development of diagnostic assays to support efforts to reduce human suffering caused by these infections.
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Adedoja A, Tijani BD, Akanbi AA, Ojurongbe TA, Adeyeba OA, Ojurongbe O. Co-endemicity of Plasmodium falciparum and Intestinal Helminths Infection in School Age Children in Rural Communities of Kwara State Nigeria. PLoS Negl Trop Dis 2015; 9:e0003940. [PMID: 26222743 PMCID: PMC4519155 DOI: 10.1371/journal.pntd.0003940] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 06/29/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Malaria and intestinal helminths co-infection are major public health problems particularly among school age children in Nigeria. However the magnitude and possible interactions of these infections remain poorly understood. This study determined the prevalence, impact and possible interaction of Plasmodium falciparum and intestinal helminths co-infection among school children in rural communities of Kwara State, Nigeria. METHODS Blood, urine and stool samples were collected from 1017 primary school pupils of ages 4-15 years. Stool samples were processed using both Kato-Katz and formol-ether concentration techniques and microscopically examined for intestinal helminths infection. Urine samples were analyzed using sedimentation method for Schistosoma haematobium. Plasmodium falciparum was confirmed by microscopy using thick and thin blood films methods and packed cell volume (PCV) was determined using hematocrit reader. Univariate analysis and chi-square statistical tests were used to analyze the data. RESULTS Overall, 61.2% of all school children had at least an infection of either P. falciparum, S. haematobium, or intestinal helminth. S. haematobium accounted for the largest proportion (44.4%) of a single infection followed by P. falciparum (20.6%). The prevalence of malaria and helminth co-infection in the study was 14.4%. Four species of intestinal helminths were recovered from the stool samples and these were hookworm (22.5%), Hymenolepis species (9.8%), Schistosoma mansoni (2.9%) and Enterobius vermicularis (0.6%). The mean densities of P. falciparum in children co-infected with S. haematobium and hookworm were higher compared to those infected with P. falciparum only though not statistically significant (p = 0.062). The age distribution of both S. haematobium (p = 0.049) and hookworm (p = 0.034) infected children were statistically significant with the older age group (10-15 years) recording the highest prevalence of 47.2% and 25% respectively. Children who were infected with S. haematobium (RR = 1.3) and hookworm (RR = 1.4) have equal chances of being infected with P. falciparum as children with no worm infection. On the other hand children infected with Hymenolepis spp. (p<0.0001) are more likely to be infected with P. falciparum than Hymenolepis spp. uninfected children (RR = 2.0). CONCLUSIONS These findings suggest that multiple parasitic infections are common in school age children in rural communities of Kwara State Nigeria. The Hymenolepis spp. induced increase susceptibility to P. falciparum could have important consequences on how concurrent infections affect the expression or pathogenesis of these infections.
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Affiliation(s)
- Ayodele Adedoja
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University of Technology, Osogbo, Nigeria
- Department of Medical Microbiology and Parasitology, University of Ilorin Teaching Hospital, Ilorin, Nigeria
| | - Bukola Deborah Tijani
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University of Technology, Osogbo, Nigeria
- Department of Medical Microbiology and Parasitology, University of Ilorin Teaching Hospital, Ilorin, Nigeria
| | - Ajibola A. Akanbi
- Department of Medical Microbiology and Parasitology, University of Ilorin, Ilorin, Nigeria
| | - Taiwo A. Ojurongbe
- Department of Mathematical and Physical Sciences, Osun State University, Osogbo, Nigeria
| | - Oluwaseyi A. Adeyeba
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University of Technology, Osogbo, Nigeria
| | - Olusola Ojurongbe
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University of Technology, Osogbo, Nigeria
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Kepha S, Nuwaha F, Nikolay B, Gichuki P, Edwards T, Allen E, Njenga SM, Mwandawiro CS, Brooker SJ. Epidemiology of coinfection with soil transmitted helminths and Plasmodium falciparum among school children in Bumula District in western Kenya. Parasit Vectors 2015; 8:314. [PMID: 26063324 PMCID: PMC4486705 DOI: 10.1186/s13071-015-0891-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 05/07/2015] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Many school children living in Africa are infected with plasmodia and helminth species and are consequently at risk of coinfection. However, the epidemiology of such coinfection and the implications of coinfection for children's health remain poorly understood. This study describes the epidemiology of Ascaris lumbricoides-Plasmodium and hookworm-Plasmodium coinfection among school children living in western Kenya and investigates the associated risk factors. METHODS As part of a randomized trial, a baseline cross-sectional survey was conducted among school children aged 5-18 years in 23 schools in Bumula District. Single stool samples were collected to screen for helminth infections using the Kato-Katz technique and malaria parasitaemia was determined from a finger prick blood sample. Demographic and anthropometric data were also collected. RESULTS Overall, 46.4% of the children were infected with Plasmodium falciparum while 27.6% of the children were infected with at least one soil transmitted helminth (STH) species, with hookworm being the most common (16.8%) followed by A. lumbricoides (15.3%). Overall 14.3% of the children had STH-Plasmodium coinfection, with hookworm-Plasmodium (9.0%) coinfection being the most common. Geographical variation in the prevalence of coinfection occurred between schools. In multivariable logistic regression analysis, hookworm was positively associated with P. falciparum infection. In stratified analysis, hookworm infection was associated with increased odds of P. falciparum infection among both boys (P < 0.001) and girls (P = 0.01), whereas there was no association between A. lumbricoides and P. falciparum. CONCLUSION These findings demonstrate STH infections are still prevalent, despite the ongoing national deworming programme in Kenya, and that malaria parasitaemia is widespread, such that coinfection occurs among a proportion of children. A subsequent trial will allow us to investigate the implications of coinfection for the risk of clinical malaria.
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Affiliation(s)
- Stella Kepha
- College of Health Sciences, Makerere University, Kampala, Uganda. .,Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
| | - Fred Nuwaha
- College of Health Sciences, Makerere University, Kampala, Uganda.
| | - Birgit Nikolay
- London School of Hygiene & Tropical Medicine, London, UK.
| | - Paul Gichuki
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
| | - Tansy Edwards
- London School of Hygiene & Tropical Medicine, London, UK.
| | | | - Sammy M Njenga
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
| | - Charles S Mwandawiro
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya.
| | - Simon J Brooker
- London School of Hygiene & Tropical Medicine, London, UK. .,KEMRI-Wellcome Trust Research Programme, Nairobi, Kenya.
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