1
|
Pooda SH, Hien DFDS, Pagabeleguem S, Heinrich AP, Porciani A, Sagna AB, Zela L, Percoma L, Lefèvre T, Dabiré RK, Koffi AA, Düring RA, Pennetier C, Moiroux N, Mouline K. Impact of blood meals taken on ivermectin-treated livestock on survival and egg production of the malaria vector Anopheles coluzzii under laboratory conditions. PLoS One 2024; 19:e0308293. [PMID: 39146278 PMCID: PMC11326554 DOI: 10.1371/journal.pone.0308293] [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: 11/24/2023] [Accepted: 07/20/2024] [Indexed: 08/17/2024] Open
Abstract
Treatment of livestock with endectocides such as ivermectin is viewed as a complementary vector control approach to address residual transmission of malaria. However, efficacy of this treatment may vary between animal species. Hence, our purpose was to investigate the effects of ivermectin treatments of common livestock species on life history traits of the opportunistic malaria vector Anopheles coluzzii. Sheep, goats and pigs were treated using injectable veterinary ivermectin formulation at the species-specific doses (recommended dose for all species and high dose in pig). Mosquito batches were exposed to treated and control (not injected) animals at different days after treatment. Daily mosquito mortality was recorded and fecundity assessed through the count of gravid females and the number of eggs they developed. The recommended dose of ivermectin induced a significant decrease in mosquito survival for up to 7 days after injection (DAI), with a decrease of 89.7%, 66.7%, and 48.4% in treated pigs, goats and sheep, respectively, compared to control animals. In treated pigs, the triple therapeutic dose decreased mosquito survival of 68.97% relatively to controls up to 14 DAI. The average number in gravid females Anopheles that survived after feeding on treated animals were reduced when blood-meals were taken on sheep (2.57% and 42.03% at 2 and 7 DAI), or on goats (decrease of the 28.28% and 73.64% respectively at 2 and 7 DAI). This study shows that ivermectin treatments to animals negatively impacts An. coluzzii life history traits and could reduce vector densities in areas where livestock live near humans. However, due to short-term efficacy of single dose treatments, repeated treatments and potentially increased dosages would be required to span the transmission season. The use of long-acting ivermectin formulations is discussed as a mean for extending efficacy while remaining cost effective.
Collapse
Affiliation(s)
- Sié Hermann Pooda
- Université de Dédougou, Dédougou (UDDG), Dédougou, Burkina Faso
- Insectarium de Bobo-Dioulasso-Campagne d'Eradication de la Mouche Tsé-tsé et de la Tryapnosomose (IBD-CETT), Bobo-Dioulasso, Burkina Faso
| | | | - Soumaïla Pagabeleguem
- Université de Dédougou, Dédougou (UDDG), Dédougou, Burkina Faso
- Insectarium de Bobo-Dioulasso-Campagne d'Eradication de la Mouche Tsé-tsé et de la Tryapnosomose (IBD-CETT), Bobo-Dioulasso, Burkina Faso
| | - Andre Patrick Heinrich
- Institute of Soil Science and Soil Conservation, Research Center for Biosystems, Land Use and Nutrition (iFZ), Justus Liebig University Giessen, Giessen, Germany
| | - Angélique Porciani
- Unité Mixte sur les Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier, IRD, CNRS, Montpellier, France
| | - André Barembaye Sagna
- Unité Mixte sur les Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier, IRD, CNRS, Montpellier, France
| | - Lamidi Zela
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), Bobo-Dioulasso, Burkina Faso
| | - Lassane Percoma
- Insectarium de Bobo-Dioulasso-Campagne d'Eradication de la Mouche Tsé-tsé et de la Tryapnosomose (IBD-CETT), Bobo-Dioulasso, Burkina Faso
| | - Thierry Lefèvre
- Unité Mixte sur les Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier, IRD, CNRS, Montpellier, France
| | - Roch Kounbobr Dabiré
- Institut de Recherche en Sciences de la Santé (IRSS), Bobo-Dioulasso, Burkina Faso
| | | | - Rolf-Alexander Düring
- Institute of Soil Science and Soil Conservation, Research Center for Biosystems, Land Use and Nutrition (iFZ), Justus Liebig University Giessen, Giessen, Germany
| | - Cédric Pennetier
- Unité Mixte sur les Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier, IRD, CNRS, Montpellier, France
| | - Nicolas Moiroux
- Unité Mixte sur les Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier, IRD, CNRS, Montpellier, France
| | - Karine Mouline
- Unité Mixte sur les Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle (MIVEGEC), Université de Montpellier, IRD, CNRS, Montpellier, France
| |
Collapse
|
2
|
Nawa M, Mupeyo-Mudala C, Banda-Tembo S, Adetokunboh O. The effects of modern housing on malaria transmission in different endemic zones: a systematic review and meta-analysis. Malar J 2024; 23:235. [PMID: 39113048 PMCID: PMC11308589 DOI: 10.1186/s12936-024-05059-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 07/27/2024] [Indexed: 08/10/2024] Open
Abstract
BACKGROUND Modern housing has been shown to reduce the risk of malaria infections compared to traditional houses; however, it is unclear if the effects differ in different malaria transmission settings. This study evaluated the effects of modern housing on malaria among different endemic areas. METHODS Electronic databases, clinical trial registries and grey literature were searched for randomized controlled trials, cohort studies, case-control studies, and cross-sectional surveys on housing done between 1987 and 2022. Forest plots were done, and the quality of evidence was assessed using the Grading of Recommendations, Assessments, Development and Evaluation Framework. RESULTS Twenty-one studies were included; thirteen were cross-sectional, four were case-control and four were cohort studies. Cohort studies showed an adjusted risk ratio of 0.68 (95% CI 0.48-0.96), and cross-sectional studies indicated an adjusted odds ratio (aOR) of 0.79 (95%CI 0.75-0.83). By endemic transmission regions, the adjusted odds ratio in the high endemic settings was 0.80 (95%CI 0.76-085); in the moderate transmission regions, aOR = 0.76 (95%CI 0.67-0.85) and in the low transmission settings, aOR = 0.67 (95%CI 0.48-0.85). CONCLUSIONS The evidence from observational studies suggests that there are no differences in the protective effects of modern houses compared to traditional houses on malaria by endemicity level. This implies that good quality modern housing protects against malaria regardless of the malaria transmission settings.
Collapse
Affiliation(s)
- Mukumbuta Nawa
- Division of Epidemiology and Biostatistics, Stellenbosch University, Stellenbosch, Western Cape, South Africa.
- Department of Epidemiology and Biostatistics, Levy Mwanawasa Medical University, Lusaka, Zambia.
| | - Catherine Mupeyo-Mudala
- Department of Epidemiology and Biostatistics, Levy Mwanawasa Medical University, Lusaka, Zambia
| | - Sylvia Banda-Tembo
- Department of Epidemiology and Biostatistics, Levy Mwanawasa Medical University, Lusaka, Zambia
| | - Olatunji Adetokunboh
- Division of Epidemiology and Biostatistics, Stellenbosch University, Stellenbosch, Western Cape, South Africa
- DSI-NRF Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA), Stellenbosch University, Stellenbosch, Western Cape, South Africa
| |
Collapse
|
3
|
Mahendran R, Pathirana S, Weerasinghe MC. Living Conditions and Malaria: A Longitudinal Study in a Rural Malaria-Endemic Area of Sri Lanka. Am J Trop Med Hyg 2024; 111:317-323. [PMID: 38889733 PMCID: PMC11310603 DOI: 10.4269/ajtmh.22-0688] [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: 11/01/2022] [Accepted: 03/25/2024] [Indexed: 06/20/2024] Open
Abstract
This study was conducted in a rural malaria-endemic community in Sri Lanka in 2014-2015 because malaria was no longer endemic in the area as of November 2012. Data on sociodemographic factors, living conditions, malaria infections, and use of mosquito protection methods during the period from 1990 to 2015 were collected through a household survey in a systematically selected sample of 724 households, covering >10% of the population in the area. Malaria incidence data were obtained from Anti-Malaria Campaign, and Malaria Research Unit of the University of Colombo. A total of 24,549 malaria cases were reported and a considerable improvement in living conditions was noted during the period covered. The association of malaria case incidence with living conditions of the community was evaluated using Spearman Rank Correlation at P <0.05. Sixty-six percent of households reported a history of malaria. The percentage of poorest type of houses (type 1) declined from 38.8% in the 1990-1994 period to 1.6% by 2015, whereas the best houses (type 5) doubled from 49.1% to 92.1% during the same period. Malaria case incidence was reported to be lowest in the best type houses (r = -0.933, P = 0.007), when pipe-borne water was available within the premises (for drinking: r = -0.846, P = 0.034; for personal hygiene: r = -0.859, P = 0.029), when water-sealed sanitary facilities were available (r = -0.956, P = 0.003), and when mosquito nets were used (r = -0.98, P = 0.001). This observed negative association may have been due to reduced human-mosquito contact.
Collapse
Affiliation(s)
| | - Sisira Pathirana
- Malaria Research Unit, Department of Parasitology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka
| | | |
Collapse
|
4
|
Nankabirwa JI, Gonahasa S, Katureebe A, Mutungi P, Nassali M, Kamya MR, Westercamp N. The Uganda housing modification study - association between housing characteristics and malaria burden in a moderate to high transmission setting in Uganda. Malar J 2024; 23:223. [PMID: 39080697 PMCID: PMC11290271 DOI: 10.1186/s12936-024-05051-5] [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: 04/24/2024] [Accepted: 07/20/2024] [Indexed: 08/02/2024] Open
Abstract
BACKGROUND Scale up of proven malaria control interventions has not been sufficient to control malaria in Uganda, emphasizing the need to explore innovative new approaches. Improved housing is one such promising strategy. This paper describes housing characteristics and their association with malaria burden in a moderate to high transmission setting in Uganda. METHODS Between October and November 2021, a household survey was conducted in 1500 randomly selected households in Jinja and Luuka districts. Information on demographics, housing characteristics, use of malaria prevention measures, and proxy indicators of wealth were collected for each household. A finger-prick blood sample was obtained for thick blood smears for malaria from all children aged 6 months to 14 years in the surveyed households. Febrile children had a malaria rapid diagnostics test (RDT) done; positive cases were managed according to national treatment guidelines. Haemoglobin was assessed in children aged < 5 years. Households were stratified as having modern houses (defined as having finished materials for roofs, walls, and floors and closed eaves) or traditional houses (those not meeting the definition of modern house). Associations between malaria burden and house type were estimated using mixed effects models and adjusted for age, wealth, and bed net use. RESULTS Most (65.5%) of the households surveyed lived in traditional houses. Most of the houses had closed eaves (85.5%), however, the use of other protective features like window/vent screens and installed ceilings was limited (0.4% had screened windows, 2.8% had screened air vents, and 5.2% had ceiling). Overall, 3,443 children were included in the clinical survey, of which 31.4% had a positive smear. RDT test positivity rate was 56.6% among children with fever. Participants living in modern houses had a significantly lower parasite prevalence by microscopy (adjusted prevalence ratio [aPR = 0.80]; 95% confidence interval [CI] 0.71 - 0.90), RDT test positivity rate (aPR = 0.90, 95%CI 0.81 - 0.99), and anaemia (aPR = 0.80, 95%CI 0.65 - 0.97) compared to those in traditional houses. CONCLUSION The study found that even after adjusting for wealth, higher quality housing had a moderate protective effect against malaria, on top of the protection already afforded by recently distributed nets.
Collapse
Affiliation(s)
- Joaniter I Nankabirwa
- Infectious Diseases Research Collaboration, Kampala, Uganda.
- Department of Internal Medicine, Makerere University College of Health Science, Kampala, Uganda.
| | | | | | - Peter Mutungi
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Martha Nassali
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Moses R Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Department of Internal Medicine, Makerere University College of Health Science, Kampala, Uganda
| | - Nelli Westercamp
- Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia
| |
Collapse
|
5
|
Gonahasa S, Nassali M, Maiteki-Sebuguzi C, Namuganga JF, Opigo J, Nabende I, Okiring J, Epstein A, Snyman K, Nankabirwa JI, Kamya MR, Dorsey G, Staedke SG. LLIN evaluation in Uganda project (LLINEUP2): association between housing construction and malaria burden in 32 districts. Malar J 2024; 23:190. [PMID: 38886782 PMCID: PMC11181653 DOI: 10.1186/s12936-024-05012-y] [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: 02/21/2024] [Accepted: 06/08/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND Well-built housing limits mosquito entry and can reduce malaria transmission. The association between community-level housing and malaria burden in Uganda was assessed using data from randomly selected households near 64 health facilities in 32 districts. METHODS Houses were classified as 'improved' (synthetic walls and roofs, eaves closed or absent) or 'less-improved' (all other construction). Associations between housing and parasitaemia were made using mixed effects logistic regression (individual-level) and multivariable fractional response logistic regression (community-level), and between housing and malaria incidence using multivariable Poisson regression. RESULTS Between November 2021 and March 2022, 4.893 children aged 2-10 years were enrolled from 3.518 houses; of these, 1.389 (39.5%) were classified as improved. Children living in improved houses had 58% lower odds (adjusted odds ratio = 0.42, 95% CI 0.33-0.53, p < 0.0001) of parasitaemia than children living in less-improved houses. Communities with > 67% of houses improved had a 63% lower parasite prevalence (adjusted prevalence ratio 0.37, 95% CI 0.19-0.70, p < 0.0021) and 60% lower malaria incidence (adjusted incidence rate ratio 0.40, 95% CI 0.36-0.44, p < 0.0001) compared to communities with < 39% of houses improved. CONCLUSIONS Improved housing was strongly associated with lower malaria burden across a range of settings in Uganda and should be utilized for malaria control.
Collapse
Affiliation(s)
- Samuel Gonahasa
- Infectious Diseases Research Collaboration, Kampala, Uganda.
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Martha Nassali
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Catherine Maiteki-Sebuguzi
- Infectious Diseases Research Collaboration, Kampala, Uganda
- National Malaria Control Division, Ministry of Health, Kampala, Uganda
| | | | - Jimmy Opigo
- National Malaria Control Division, Ministry of Health, Kampala, Uganda
| | - Isaiah Nabende
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Jaffer Okiring
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Adrienne Epstein
- Department of Medicine, University of California San Francisco, San Francisco, USA
| | - Katherine Snyman
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Department of Global Health and Development, London School of Hygiene & Tropical Medicine, London, UK
- Department of Clinical Research, London School of Hygiene & Tropical Medicine, London, UK
| | - Joaniter I Nankabirwa
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Department of Medicine, Makerere University, Kampala, Uganda
| | - Moses R Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Department of Medicine, Makerere University, Kampala, Uganda
| | - Grant Dorsey
- Department of Medicine, University of California San Francisco, San Francisco, USA
| | - Sarah G Staedke
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| |
Collapse
|
6
|
Talib J, Abatan AA, HoekSpaans R, Yamba EI, Egbebiyi TS, Caminade C, Jones A, Birch CE, Olagbegi OM, Morse AP. The effect of explicit convection on simulated malaria transmission across Africa. PLoS One 2024; 19:e0297744. [PMID: 38625879 PMCID: PMC11020401 DOI: 10.1371/journal.pone.0297744] [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: 08/18/2023] [Accepted: 01/11/2024] [Indexed: 04/18/2024] Open
Abstract
Malaria transmission across sub-Saharan Africa is sensitive to rainfall and temperature. Whilst different malaria modelling techniques and climate simulations have been used to predict malaria transmission risk, most of these studies use coarse-resolution climate models. In these models convection, atmospheric vertical motion driven by instability gradients and responsible for heavy rainfall, is parameterised. Over the past decade enhanced computational capabilities have enabled the simulation of high-resolution continental-scale climates with an explicit representation of convection. In this study we use two malaria models, the Liverpool Malaria Model (LMM) and Vector-Borne Disease Community Model of the International Centre for Theoretical Physics (VECTRI), to investigate the effect of explicitly representing convection on simulated malaria transmission. The concluded impact of explicitly representing convection on simulated malaria transmission depends on the chosen malaria model and local climatic conditions. For instance, in the East African highlands, cooler temperatures when explicitly representing convection decreases LMM-predicted malaria transmission risk by approximately 55%, but has a negligible effect in VECTRI simulations. Even though explicitly representing convection improves rainfall characteristics, concluding that explicit convection improves simulated malaria transmission depends on the chosen metric and malaria model. For example, whilst we conclude improvements of 45% and 23% in root mean squared differences of the annual-mean reproduction number and entomological inoculation rate for VECTRI and the LMM respectively, bias-correcting mean climate conditions minimises these improvements. The projected impact of anthropogenic climate change on malaria incidence is also sensitive to the chosen malaria model and representation of convection. The LMM is relatively insensitive to future changes in precipitation intensity, whilst VECTRI predicts increased risk across the Sahel due to enhanced rainfall. We postulate that VECTRI's enhanced sensitivity to precipitation changes compared to the LMM is due to the inclusion of surface hydrology. Future research should continue assessing the effect of high-resolution climate modelling in impact-based forecasting.
Collapse
Affiliation(s)
- Joshua Talib
- U.K. Centre for Ecology and Hydrology (UKCEH), Wallingford, United Kingdom
| | - Abayomi A. Abatan
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom
| | - Remy HoekSpaans
- Liverpool School of Tropical Medicine (LSTM), Liverpool, United Kingdom
| | - Edmund I. Yamba
- Department of Meteorology and Climate Science, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Temitope S. Egbebiyi
- Climate Systems Analysis Group, Department of Environmental and Geographical Science, University of Cape Town, Cape Town, South Africa
| | - Cyril Caminade
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
- The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy
| | - Anne Jones
- International Business Machines (IBM) Research Europe, Daresbury, United Kingdom
| | - Cathryn E. Birch
- School of Earth and Environment, University of Leeds, Leeds, United Kingdom
| | - Oladapo M. Olagbegi
- School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Andrew P. Morse
- School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom
| |
Collapse
|
7
|
Tizifa TA, Kabaghe AN, McCann RS, Gowelo S, Malenga T, Nkhata RM, Chapeta Y, Nkhono W, Kadama A, Takken W, Phiri KS, van Vugt M, van den Berg H, Manda-Taylor L. Assessing the implementation fidelity, feasibility, and sustainability of community-based house improvement for malaria control in southern Malawi: a mixed-methods study. BMC Public Health 2024; 24:951. [PMID: 38566043 PMCID: PMC10988826 DOI: 10.1186/s12889-024-18401-4] [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: 09/18/2023] [Accepted: 03/20/2024] [Indexed: 04/04/2024] Open
Abstract
BACKGROUND Despite significant success in the fight against malaria over the past two decades, malaria control programmes rely on only two insecticidal methods: indoor residual spraying and insecticidal-treated nets. House improvement (HI) can complement these interventions by reducing human-mosquito contact, thereby reinforcing the gains in disease reduction. This study assessed the implementation fidelity, which is the assessment of how closely an intervention aligns with its intended design, feasibility, and sustainability of community-led HI in southern Malawi. METHODS The study, conducted in 22 villages (2730 households), employed a mixed-methods approach. Implementation fidelity was assessed using a modified framework, with longitudinal surveys collecting data on HI coverage indicators. Quantitative analysis, employing descriptive statistics, evaluated the adherence to HI implementation. Qualitative data came from in-depth interviews, key informant interviews, and focus groups involving project beneficiaries and implementers. Qualitative data were analysed using content analysis guided by the implementation fidelity model to explore facilitators, challenges, and factors affecting intervention feasibility. RESULTS The results show that HI was implemented as planned. There was good adherence to the intended community-led HI design; however, the adherence could have been higher but gradually declined over time. In terms of intervention implementation, 74% of houses had attempted to have eaves closed in 2016-17 and 2017-18, compared to 70% in 2018-19. In 2016-17, 42% of houses had all four sides of the eaves closed, compared to 33% in 2018-19. Approximately 72% of houses were screened with gauze wire in 2016-17, compared to 57% in 2018-19. High costs, supply shortages, labour demands, volunteers' poor living conditions and adverse weather were reported to hinder the ideal HI implementation. Overall, the community described community-led HI as feasible and could be sustained by addressing these socioeconomic and contextual challenges. CONCLUSION Our study found that although HI was initially implemented as planned, its fidelity declined over time. Using trained volunteers facilitated the fidelity and feasibility of implementing the intervention. A combination of rigorous community education, consistent training, information, education and communication, and intervention modifications may be necessary to address the challenges and enhance the intervention's fidelity, feasibility, and sustainability.
Collapse
Affiliation(s)
- Tinashe A Tizifa
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, University of Amsterdam, Amsterdam University Medical Center, Location Academic Medical Center, Amsterdam, The Netherlands.
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi.
| | - Alinune N Kabaghe
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Robert S McCann
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
- Centre for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, USA
| | - Steven Gowelo
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - Tumaini Malenga
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
- National TB and Leprosy Elimination Programme, Ministry of Health, Lilongwe, Malawi
| | - Richard M Nkhata
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Yankho Chapeta
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
- Biological Sciences Department, Mzuzu University, Mzuzu, Malawi
| | - William Nkhono
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Asante Kadama
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Willem Takken
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - Kamija S Phiri
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Michele van Vugt
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, University of Amsterdam, Amsterdam University Medical Center, Location Academic Medical Center, Amsterdam, The Netherlands
| | - Henk van den Berg
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - Lucinda Manda-Taylor
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| |
Collapse
|
8
|
Gallalee S, Zarlinda I, Silaen MG, Cotter C, Cueto C, Elyazar IRF, Jacobson JO, Gosling R, Hsiang MS, Bennett A, Coutrier FN, Smith JL. Forest-goers as a heterogeneous population at high-risk for malaria: a case-control study in Aceh Province, Indonesia. Malar J 2024; 23:37. [PMID: 38291392 PMCID: PMC10826189 DOI: 10.1186/s12936-024-04856-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 01/20/2024] [Indexed: 02/01/2024] Open
Abstract
BACKGROUND A major challenge to malaria elimination is identifying and targeting populations that are harbouring residual infections and contributing to persistent transmission. In many near-elimination settings in Southeast Asia, it is known that forest-goers are at higher risk for malaria infection, but detailed information on their behaviours and exposures is not available. METHODS In Aceh Province, Indonesia, a near-elimination setting where a growing proportion of malaria is due to Plasmodium knowlesi, a case-control study was conducted to identify risk factors for symptomatic malaria, characteristics of forest-goers, and key intervention points. From April 2017 to September 2018, cases and controls were recruited and enrolled in a 1:3 ratio. Cases had confirmed malaria infection by rapid diagnostic test or microscopy detected at a health facility (HF). Gender-matched controls were recruited from passive case detection among individuals with suspected malaria who tested negative at a health facility (HF controls), and community-matched controls were recruited among those testing negative during active case detection. Multivariable logistic regression (unconditional for HF controls and conditional for community controls) was used to identify risk factors for symptomatic malaria infection. RESULTS There were 45 cases, of which 27 were P. knowlesi, 17 were Plasmodium vivax, and one was not determined. For controls, 509 and 599 participants were recruited from health facilities and the community, respectively. Forest exposures were associated with high odds of malaria; in particular, working and sleeping in the forest (HF controls: adjusted odds ratio (aOR) 21.66, 95% CI 5.09-92.26; community controls: aOR 16.78, 95% CI 2.19-128.7) and having a second residence in the forest (aOR 6.29, 95% CI 2.29-17.31 and 13.53, 95% CI 2.10-87.12). Male forest-goers were a diverse population employed in a variety of occupations including logging, farming, and mining, sleeping in settings, such as huts, tents, and barracks, and working in a wide range of group sizes. Reported use of protective measures, such as nets, hammock nets, mosquito coils, and repellents was low among forest-goers and interventions at forest residences were absent. CONCLUSIONS Second residences in the forest and gaps in use of protective measures point to key malaria interventions to improve coverage in forest-going populations at risk for P. knowlesi and P. vivax in Aceh, Indonesia. Intensified strategies tailored to specific sub-populations will be essential to achieve elimination.
Collapse
Affiliation(s)
- Sarah Gallalee
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA.
| | - Iska Zarlinda
- Malaria Pathogenesis Unit, Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Martha G Silaen
- Malaria Pathogenesis Unit, Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Chris Cotter
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
- Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden
| | - Carmen Cueto
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Iqbal R F Elyazar
- Eijkman-Oxford Clinical Research Unit, Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Jerry O Jacobson
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Roly Gosling
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | - Michelle S Hsiang
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, USA
- Department of Pediatrics, University of California San Francisco, Benioff Children's Hospital, San Francisco, CA, USA
| | - Adam Bennett
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, USA
| | - Farah N Coutrier
- Malaria Pathogenesis Unit, Eijkman Institute for Molecular Biology, Jakarta, Indonesia
- Eijkman Research Center for Molecular Biology, National Research and Innovation Agency (BRIN), Jakarta, Indonesia
| | - Jennifer L Smith
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, USA
| |
Collapse
|
9
|
Abong’o B, Agumba S, Moshi V, Simwero J, Otima J, Ochomo E. Insecticide treated eaves screens provide additional marginal protection compared to untreated eave screens under semi-field conditions in western Kenya. MALARIAWORLD JOURNAL 2024; 15:1. [PMID: 38322708 PMCID: PMC10842374 DOI: 10.5281/zenodo.10567425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
Introduction Human habitats remain the main point of human-vector interaction leading to malaria transmission despite the sustained use of insecticide-treated nets and indoor residual spraying. Simple structural modifications involving screening of doors, windows and eaves have great potential for reducing indoor entry of mosquitoes. Moreover, insecticide treatment of the screen material may provide additional benefit in mosquito population reduction. Materials and Methods Four huts, each constructed inside a semi-field structure, were used in the study. Two had untreated eave and door screens and screened air cavities in place of windows (experiment 1) or were similar but with the eave screens treated with Actellic® 300CS insecticide (experiment 2). The other two huts remained unscreened throughout the study. Two hundred, 3-day old adults of F1 generation Anopheles funestus collected by aspiration or F0 reared from An. arabiensis larvae or An. arabiensis (Dongola strain) were released in each semi-field structure at dusk and recaptured the following morning. A single volunteer slept in each hut under an untreated bednet each night of the study. Recaptured mosquitoes were counted and recorded by location, either indoor or outdoor of each hut in the different semi-field structures. Results Based on modelled estimates, significantly fewer, 10% An. arabiensis from Ahero, 11% An. arabiensis Dongola strain and 10% An. funestus from Siaya were observed inside modified huts compared to unmodified ones. Treating of eave screen material with Actellic® 300CS significantly reduced indoor numbers of An. arabiensis from Ahero, to nearly 0%, and An. arabiensis Dongola strain, to 3%, compared to huts with untreated eave screens, while eliminating An. funestus indoors. These modifications cost US$180 /structure and have been observed to last more than 15 years in a different location. Conclusions Eave, door and window screening are effective ways of reducing mosquito entry into houses. Additionally, treatment of eave screen material with an effective insecticide further reduces the Anopheles population in and around the screened huts under semi-field conditions and could greatly complement existing vector control efforts.
Collapse
Affiliation(s)
- Bernard Abong’o
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
- Research World Limited, Kisumu, Kenya
| | - Silas Agumba
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Vincent Moshi
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Jacob Simwero
- Habitat for Humanity International, Lenana Road, Nairobi
| | - Jane Otima
- Habitat for Humanity International, Lenana Road, Nairobi
| | - Eric Ochomo
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
- Research World Limited, Kisumu, Kenya
| |
Collapse
|
10
|
Searle KM, Earland DE, Francisco Bibe A, Novela A, Muhiro V, Ferrão JL. Long-lasting household damage from Cyclone Idai increases malaria risk in rural western Mozambique. Sci Rep 2023; 13:21590. [PMID: 38062239 PMCID: PMC10703775 DOI: 10.1038/s41598-023-49200-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 12/05/2023] [Indexed: 12/18/2023] Open
Abstract
Cyclone Idai in 2019 was one of the worst tropical cyclones recorded in the Southern Hemisphere. The storm caused catastrophic damage and led to a humanitarian crisis in Mozambique. The affected population suffered a cholera epidemic on top of housing and infrastructure damage and loss of life. The housing and infrastructure damage sustained during Cyclone Idai still has not been addressed in all affected communities. This is of grave concern because storm damage results in poor housing conditions which are known to increase the risk of malaria. Mozambique has the 4th highest malaria prevalence in sub-Saharan Africa and is struggling to control malaria in most of the country. We conducted a community-based cross-sectional survey in Sussundenga Village, Manica Province, Mozambique in December 2019-February 2020. We found that most participants (64%) lived in households that sustained damage during Cyclone Idai. The overall malaria prevalence was 31% measured by rapid diagnostic test (RDT). When controlling for confounding variables, the odds of malaria infection was nearly threefold higher in participants who lived in households damaged by Cyclone Idai nearly a year after the storm. This highlights the need for long-term disaster response to improve the efficiency and success of malaria control efforts.
Collapse
Affiliation(s)
- Kelly M Searle
- University of Minnesota School of Public Health, Minneapolis, MN, USA.
| | | | | | - Anísio Novela
- Direcção Distrital de Saúde de Sussundenga, Sussundenga, Manica, Mozambique
| | - Vali Muhiro
- Direcção Distrital de Saúde de Sussundenga, Sussundenga, Manica, Mozambique
| | - João L Ferrão
- Consultores Associados de Manica, Sussundenga, Mozambique
| |
Collapse
|
11
|
Yared S, Gebresilassie A, Aklilu E, Abdulahi E, Kirstein OD, Gonzalez-Olvera G, Che-Mendoza A, Bibiano-Marin W, Waymire E, Lines J, Lenhart A, Kitron U, Carter T, Manrique-Saide P, Vazquez-Prokopec GM. Building the vector in: construction practices and the invasion and persistence of Anopheles stephensi in Jigjiga, Ethiopia. Lancet Planet Health 2023; 7:e999-e1005. [PMID: 38056970 DOI: 10.1016/s2542-5196(23)00250-4] [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: 05/22/2023] [Revised: 10/26/2023] [Accepted: 10/30/2023] [Indexed: 12/08/2023]
Abstract
Anopheles stephensi is a major vector of malaria in Asia and the Arabian Peninsula, and its recent invasion into Africa poses a major threat to malaria control and elimination efforts on the continent. The mosquito is well adapted to urban environments, and its presence in Africa could potentially lead to an increase in malaria transmission in cities. Most of the knowledge about An stephensi ecology in Africa has been generated from studies conducted during the rainy season, when vectors are most abundant. Here, we provide evidence from the peak of the dry season in the city of Jigjiga in Ethiopia, and report An stephensi immature stages infesting predominantly in water reservoirs made to support construction operations (ie, in construction sites or associated with brick-manufacturing businesses). Political and economic changes in Ethiopia (particularly the Somali Region) have fuelled an unprecedented construction boom since 2018 that, in our opinion, has been instrumental in the establishment, persistence, and propagation of An stephensi via the year-round availability of perennial larval habitats associated with construction. We argue that larval source management during the dry season might provide a unique opportunity for focused control of An stephensi in Jigjiga and similar areas.
Collapse
Affiliation(s)
- Solomon Yared
- Department of Biology, Jigjiga University, Jigjiga, Ethiopia
| | - Araya Gebresilassie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Esayas Aklilu
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Elyas Abdulahi
- Population, Resources and Environmental Economics, Jigjiga University, Jigjiga, Ethiopia
| | | | - Gabriela Gonzalez-Olvera
- Collaborative Unit for Entomological Bioassays, Autonomous University of Yucatan, Mérida, Mexico
| | - Azael Che-Mendoza
- Collaborative Unit for Entomological Bioassays, Autonomous University of Yucatan, Mérida, Mexico
| | - Wilbert Bibiano-Marin
- Collaborative Unit for Entomological Bioassays, Autonomous University of Yucatan, Mérida, Mexico
| | | | - Jo Lines
- London School of Public Health, London, UK
| | - Audrey Lenhart
- Entomology Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Uriel Kitron
- Department of Environmental Sciences, Emory University, Atlanta, GA, USA
| | - Tamar Carter
- Department of Biology, Baylor University, Wako, TX, USA
| | - Pablo Manrique-Saide
- Collaborative Unit for Entomological Bioassays, Autonomous University of Yucatan, Mérida, Mexico
| | | |
Collapse
|
12
|
Kathet S, Sudi W, Mwingira V, Tungu P, Aalto M, Hakala T, Honkala M, Malima R, Kisinza W, Meri S, Khattab A. Efficacy of 3D screens for sustainable mosquito control: a semi-field experimental hut evaluation in northeastern Tanzania. Parasit Vectors 2023; 16:417. [PMID: 37964334 PMCID: PMC10647037 DOI: 10.1186/s13071-023-06032-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 10/24/2023] [Indexed: 11/16/2023] Open
Abstract
BACKGROUND A three-dimensional window screen (3D-Screen) has been developed to create a window double-screen trap (3D-WDST), effectively capturing and preventing the escape of mosquitoes. A 2015 laboratory study demonstrated the 3D-Screen's efficacy, capturing 92% of mosquitoes in a double-screen setup during wind tunnel assays. To further evaluate its effectiveness, phase II experimental hut trials were conducted in Muheza, Tanzania. METHODS Three experimental hut trials were carried out between 2016 and 2017. Trial I tested two versions of the 3D-WDST in huts with open or closed eaves, with one version using a single 3D-Screen and the other using two 3D-Screens. Trial II examined the 3D-WDST with two 3D-Screens in huts with or without baffles, while Trial III compared handmade and machine-made 3D structures. Mosquito capturing efficacy of the 3D-WDST was measured by comparing the number of mosquitoes collected in the test hut to a control hut with standard exit traps. RESULTS Trial I showed that the 3D-WDST with two 3D-Screens used in huts with open eaves achieved the highest mosquito-capturing efficacy. This treatment captured 33.11% (CI 7.40-58.81) of female anophelines relative to the total collected in this hut (3D-WDST and room collections) and 27.27% (CI 4.23-50.31) of female anophelines relative to the total collected in the control hut (exit traps, room, and verandahs collections). In Trial II, the two 3D-Screens version of the 3D-WDST captured 70.32% (CI 56.87-83.77) and 51.07% (CI 21.72-80.41) of female anophelines in huts with and without baffles, respectively. Compared to the control hut, the capturing efficacy for female anophelines was 138.6% (37.23-239.9) and 42.41% (14.77-70.05) for huts with and without baffles, respectively. Trial III demonstrated similar performance between hand- and machine-made 3D structures. CONCLUSIONS The 3D-WDST proved effective in capturing malaria vectors under semi-field experimental hut conditions. Using 3D-Screens on both sides of the window openings was more effective than using a single-sided 3D-Screen. Additionally, both hand- and machine-made 3D structures exhibited equally effective performance, supporting the production of durable cones on an industrial scale for future large-scale studies evaluating the 3D-WDST at the community level.
Collapse
Affiliation(s)
- Subam Kathet
- Department of Bacteriology and Immunology, Haartman Institute, and Translational Immunology Research Program, University of Helsinki, 00014, Helsinki, Finland
| | - Wema Sudi
- Amani Medical Research Centre, National Institute for Medical Research, Muheza, Tanzania
| | - Victor Mwingira
- Amani Medical Research Centre, National Institute for Medical Research, Muheza, Tanzania
| | - Patrick Tungu
- Amani Medical Research Centre, National Institute for Medical Research, Muheza, Tanzania
| | | | - Tomi Hakala
- Department of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere, Finland
| | - Markku Honkala
- Department of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere, Finland
| | - Robert Malima
- Amani Medical Research Centre, National Institute for Medical Research, Muheza, Tanzania
| | - William Kisinza
- Amani Medical Research Centre, National Institute for Medical Research, Muheza, Tanzania
| | - Seppo Meri
- Department of Bacteriology and Immunology, Haartman Institute, and Translational Immunology Research Program, University of Helsinki, 00014, Helsinki, Finland
- HUSLAB Diagnostic Center, Helsinki University Central Hospital, N00029, Helsinki, Finland
| | - Ayman Khattab
- Department of Bacteriology and Immunology, Haartman Institute, and Translational Immunology Research Program, University of Helsinki, 00014, Helsinki, Finland.
- Department of Nucleic Acid Research, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, New Borg El-Arab City, 21934, Alexandria, Egypt.
| |
Collapse
|
13
|
Naserrudin NA, Lin PYP, Monroe A, Baumann SE, Adhikari B, Miller AC, Sato S, Fornace KM, Culleton R, Cheah PY, Hod R, Jeffree MS, Ahmed K, Hassan MR. Disentangling the intersection of inequities with health and malaria exposure: key lessons from rural communities in Northern Borneo. Malar J 2023; 22:343. [PMID: 37946259 PMCID: PMC10636872 DOI: 10.1186/s12936-023-04750-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/11/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND The increasing incidence of Plasmodium knowlesi malaria poses a significant challenge to efforts to eliminate malaria from Malaysia. Macaque reservoirs, outdoors-biting mosquitoes, human activities, and agricultural work are key factors associated with the transmission of this zoonotic pathogen. However, gaps in knowledge regarding reasons that drive malaria persistence in rural Kudat, Sabah, Northern Borneo remain. This study was conducted to address this knowledge gap, to better understand the complexities of these entangled problems, and to initiate discussion regarding new countermeasures to address them. This study aims to highlight rural community members' perspectives regarding inequities to health relating to P. knowlesi malaria exposure. METHODS From January to October 2022, a study using qualitative methods was conducted in four rural villages in Kudat district of Sabah, Malaysia. A total of nine in-depth interviews were conducted with community and faith leaders, after the completion of twelve focus group discussions with 26 photovoice participants. The interviews were conducted using the Sabah Malay dialect, audio-recorded, transcribed, and translated into English. The research team led the discussion and analysis, which was approved by participants through member checking at the community level. RESULTS Participants identified disparity in health as a key issue affecting their health and livelihoods. Injustice in the social environment was also identified as a significant challenge, including the importance of listening to the voices of affected communities in disentangling the social and economic phenomena that can impact malaria control. Specific concerns included inadequate access to health-related resources and degradation of the environment. Participants recommended improving access to water and other necessities, increasing the availability of malaria control commodities in healthcare facilities, and developing sustainable programs to reduce socioeconomic disparities. CONCLUSION Inequities to health emerged as a key concern for malaria control in rural Kudat, Sabah. A locally targeted malaria programme cantered on improving the social and economic disparities associated with health outcomes, could be a potential strategy for malaria prevention in such areas. Community-level perspectives gathered from this study can be used as a foundation for future discussions and dialogues among policymakers and community members for achieving greater transparency, improving social equity, and interoperability in addressing P. knowlesi malaria control.
Collapse
Affiliation(s)
- Nurul Athirah Naserrudin
- Department of Public Health Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000, Kuala Lumpur, Malaysia
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Sabah, Malaysia
- Sabah State Health Department, Ministry of Health, 88590, Kota Kinabalu, Malaysia
| | - Pauline Yong Pau Lin
- Faculty of Social Sciences and Humanities, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Malaysia
| | - April Monroe
- Johns Hopkins Center for Communication Programs, Baltimore, MD, USA
| | - Sara Elizabeth Baumann
- Department of Behavioral and Community Health Sciences, University of Pittsburgh School of Public Health, Pittsburgh, PA, 15261, USA
| | - Bipin Adhikari
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Shigeharu Sato
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Sabah, Malaysia
- Department of Pathology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Malaysia
| | - Kimberly M Fornace
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, UK
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Richard Culleton
- Division of Molecular Parasitology, Proteo-Science Center, Ehime University, Toon, Ehime, 791-0295, Japan
| | - Phaik Yeong Cheah
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- The Ethox Centre, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Rozita Hod
- Department of Public Health Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000, Kuala Lumpur, Malaysia
| | - Mohammad Saffree Jeffree
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Sabah, Malaysia
- Department of Public Health Medicine, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Malaysia
| | - Kamruddin Ahmed
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Sabah, Malaysia
- Department of Pathology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Malaysia
| | - Mohd Rohaizat Hassan
- Department of Public Health Medicine, Faculty of Medicine, Universiti Kebangsaan Malaysia, 56000, Kuala Lumpur, Malaysia.
- Borneo Medical and Health Research Centre, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, 88400, Kota Kinabalu, Sabah, Malaysia.
| |
Collapse
|
14
|
Tarimo FS, Dillip A, Kosia EM, Lwetoijera DW. Community perception of the autodissemination of pyriproxyfen for controlling malaria vectors in south-eastern Tanzania. Malar J 2023; 22:333. [PMID: 37924148 PMCID: PMC10625276 DOI: 10.1186/s12936-023-04773-2] [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: 06/12/2023] [Accepted: 10/26/2023] [Indexed: 11/06/2023] Open
Abstract
BACKGROUND The efficacy of the autodissemination of pyriproxyfen to control malaria vectors has been demonstrated under semi field environment in Tanzania. However, the information on how best communities should be engaged for its routine and large-scale adoption are lacking. This study assessed the community's level of knowledge, perceptions, acceptability of the autodissemination of pyriproxyfen, and the perceived risks on the safety of pyriproxyfen on the environment. METHODS This was a concurrent mixed methods study, comprised of a community-based survey of 400 household representatives and eight focus group discussions (FGDs). The study was conducted in two villages in Mlimba district in south-eastern Tanzania between June and August 2022. For the quantitative data analysis, descriptive statistics were applied using R software, while inductive approach was used for qualitative data analysis, using NVivo software. RESULTS Knowledge on autodissemination of pyriproxyfen approach was found to be relatively low among both the FGD respondents and surveyed community members (36%, n = 144). Nevertheless, when it was explained to them, the envisioned community support for the autodissemination approach was relatively high (97%, n = 388). One of the major perceived benefits of the autodissemination of pyriproxyfen was the reduction of malaria-transmitting mosquitoes and associated malaria transmission. Environmental impact of pyriproxyfen on non-target organisms and health risk to children were among the major concerns. When provided with information on the safety and its utilization particularly through autodissemination approach, 93.5% (n = 374) of the survey respondents said that they would allow the PPF-contaminated pots to be placed around their homes. Similarly, FGD respondents were receptive towards the autodissemination of pyriproxyfen, but emphasized on the need for raising awareness among community members before related field trials. CONCLUSION This study indicates a low knowledge but high support for scaling up of the autodissemination of pyriproxyfen as a complementary tool for malaria control in rural Tanzania. The Findings of this study suggest that community sensitization activities are required to improve the community's acceptability and trust of the approach before respective field trials.
Collapse
Affiliation(s)
- Felista S Tarimo
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, United Republic of Tanzania.
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania.
| | - Angel Dillip
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, United Republic of Tanzania
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania
- Apotheker Health Access Initiative, P. O. Box 70022, Dar es Salaam, United Republic of Tanzania
| | - Efraim M Kosia
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania
| | - Dickson W Lwetoijera
- Environmental Health and Ecological Sciences Department, Ifakara Health Institute, P. O. Box 53, Ifakara, United Republic of Tanzania.
- School of Life Sciences and Bio Engineering, The Nelson Mandela, African Institution of Science and Technology, P. O. Box 4447, Tengeru, Arusha, United Republic of Tanzania.
| |
Collapse
|
15
|
N'Guessan R, Assi SB, Koffi A, Ahoua Alou PL, Mian A, Achee NL, Fustec B, Grieco JP, Liu F, Kumar S, Noffsinger M, Hudson A, Möhlmann TWR, Farenhorst M. EaveTubes for control of vector-borne diseases in Côte d'Ivoire: study protocol for a cluster randomized controlled trial. Trials 2023; 24:704. [PMID: 37919815 PMCID: PMC10621221 DOI: 10.1186/s13063-023-07639-9] [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: 06/28/2023] [Accepted: 09/11/2023] [Indexed: 11/04/2023] Open
Abstract
BACKGROUND Vector control tools, long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), have significantly contributed to malaria prevention efforts in sub-Saharan Africa. However, insecticide resistance has seriously hampered their efficacy in recent years and new tools are essential to further progress. In2Care® EaveTubes (ETs) are an inexpensive, new resistance-breaking vector control product under World Health Organization (WHO) evaluation informed by mosquito ecology to efficiently target malaria vectors. By installing ETs in the walls of the house at the eave level that funnel the natural airflow, mosquitoes are drawn in by the same heat and odor cues that typically attract them through open eaves. Once inside an ET, mosquitoes are exposed to insecticide-treated netting placed inside the ET. The aim of this study is to test whether ETs as stand-alone tool have an effect on the epidemiology of malaria in villages where houses have been modified with the ET intervention. METHODS A two-armed, cluster randomized controlled trial will be conducted to evaluate the effect of ETs on clinical malaria incidence in children living in Côte d'Ivoire. Thirty-four villages will be selected based on population size and the proportion of houses suitable for modification with ETs (17 treatment arms (ETs + LLINs, 17 control arms (LLINs only)). Based on the population census, 55 households per cluster with eligible children (i.e., between the ages of 6 months to 8 years old at the start of the study) will be randomly selected for recruitment into the active detection cohorts. In the treatment arm, we will enroll eligible children who reside in ET-treated houses. The intervention and control cohorts will be followed for 4 months for baseline covariate measurements and 24 months with intervention. During case detection visits, blood samples will be taken from all febrile children and tested for malaria infection with rapid diagnostic tests (RDTs). All positive clinical malaria infections will be treated. To estimate the impact of the ET on malaria vector densities, entomological measurements (indoor sampling with CDC traps) will be conducted monthly in 20 clusters (10 ET, 10 Control) in 10 randomly selected households per cluster. To estimate the infectiousness of malaria vectors, sporozoite rates will be measured in subsets of the collected mosquito samples. DISCUSSION Findings will serve as an efficacy trial of ETs and will be submitted to the WHO Vector Control Advisory Group (VCAG) for assessment of public health value. Entomological outcomes will also be measured as proxies of malaria transmission to help develop guidelines for the evaluation of future In2Care® ETs products. TRIAL REGISTRATION ClinicalTrials.gov NCT05736679. Registered on 10 February 2023.
Collapse
Affiliation(s)
- Raphael N'Guessan
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | - Serge-Brice Assi
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | - Alphonsine Koffi
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | | | - Anatole Mian
- Vector Control Product Evaluation Centre/Institut Pierre Richet, Bouaké, Côte d'Ivoire
| | | | | | | | - Fang Liu
- University of Notre Dame, Notre Dame, IN, USA
| | - Santosh Kumar
- Keough School of Global Affairs, University of Notre Dame, Notre Dame, IN, USA
| | | | | | | | | |
Collapse
|
16
|
Semakula HM, Liang S, Mukwaya PI, Mugagga F, Nseka D, Wasswa H, Mwendwa P, Kayima P, Achuu SP, Nakato J. Bayesian belief network modelling approach for predicting and ranking risk factors for malaria infections among children under 5 years in refugee settlements in Uganda. Malar J 2023; 22:297. [PMID: 37794401 PMCID: PMC10552276 DOI: 10.1186/s12936-023-04735-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 09/29/2023] [Indexed: 10/06/2023] Open
Abstract
BACKGROUND Malaria risk factors at household level are known to be complex, uncertain, stochastic, nonlinear, and multidimensional. The interplay among these factors, makes targeted interventions, and resource allocation for malaria control challenging. However, few studies have demonstrated malaria's transmission complexity, control, and integrated modelling, with no available evidence on Uganda's refugee settlements. Using the 2018-2019 Uganda's Malaria Indicator Survey (UMIS) data, an alternative Bayesian belief network (BBN) modelling approach was used to analyse, predict, rank and illustrate the conceptual reasoning, and complex causal relationships among the risk factors for malaria infections among children under-five in refugee settlements of Uganda. METHODS In the UMIS, household level information was obtained using standardized questionnaires, and a total of 675 children under 5 years were tested for malaria. From the dataset, a casefile containing malaria test results, demographic, social-economic and environmental information was created. The casefile was divided into a training (80%, n = 540) and testing (20%, n = 135) datasets. The training dataset was used to develop the BBN model following well established guidelines. The testing dataset was used to evaluate model performance. RESULTS Model accuracy was 91.11% with an area under the receiver-operating characteristic curve of 0.95. The model's spherical payoff was 0.91, with the logarithmic, and quadratic losses of 0.36, and 0.16 respectively, indicating a strong predictive, and classification ability of the model. The probability of refugee children testing positive, and negative for malaria was 48.1% and 51.9% respectively. The top ranked malaria risk factors based on the sensitivity analysis included: (1) age of child; (2) roof materials (i.e., thatch roofs); (3) wall materials (i.e., poles with mud and thatch walls); (4) whether children sleep under insecticide-treated nets; 5) type of toilet facility used (i.e., no toilet facility, and pit latrines with slabs); (6) walk time distance to water sources (between 0 and 10 min); (7) drinking water sources (i.e., open water sources, and piped water on premises). CONCLUSION Ranking, rather than the statistical significance of the malaria risk factors, is crucial as an approach to applied research, as it helps stakeholders determine how to allocate resources for targeted malaria interventions within the constraints of limited funding in the refugee settlements.
Collapse
Affiliation(s)
- Henry Musoke Semakula
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda.
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, 2055 Mowry Rd, Gainesville, FL, 32610, USA.
- Department of Environmental Health Sciences, School of Public Health & Health Sciences, University of Massachusetts, Amherst, 01003, USA.
| | - Song Liang
- Department of Environmental Health Sciences, School of Public Health & Health Sciences, University of Massachusetts, Amherst, 01003, USA
| | - Paul Isolo Mukwaya
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
| | - Frank Mugagga
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
| | - Denis Nseka
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
| | - Hannington Wasswa
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
| | - Patrick Mwendwa
- Department of Horticulture and Food Security, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Nairobi, Kenya
| | - Patrick Kayima
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
| | - Simon Peter Achuu
- National Environmental Management Authority (NEMA), Plot 17/19/21 Jinja Road, P.O. Box 22255, Kampala, Uganda
| | - Jovia Nakato
- Department of Geography, Geo-informatics and Climatic Sciences, Makerere University, P.O Box 7062, Kampala, Uganda
| |
Collapse
|
17
|
Hasyim H, Dewi WC, Lestari RAF, Flora R, Novrikasari N, Liberty IA, Marini H, Elagali A, Herlinda S, Maharani FE. Risk factors of malaria transmission in mining workers in Muara Enim, South Sumatra, Indonesia. Sci Rep 2023; 13:14755. [PMID: 37679466 PMCID: PMC10484942 DOI: 10.1038/s41598-023-40418-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 08/09/2023] [Indexed: 09/09/2023] Open
Abstract
Eliminating malaria by 2030 is stated as goal three in the UN's Sustainable Development Goals (SDGs). However, malaria still remains a significant public health problem. This study aims to identify the factors determining malaria transmission in artisanal or small-scale miner (ASM) communities in three villages: Tanjung Agung, Tanjung Lalang, and Penyandingan, located in the Tanjung Enim District, Muara Enim, South Sumatra, Indonesia. Researchers conducted a cross-sectional study involving 92 participants from the study area. They used a logistic regression model to investigate the risk factors related to malaria occurrence. The multivariable analysis revealed that age (Adjusted Prevalence Ratio (APR) = 7.989 with 95% CI 1.724-37.002) and mosquito breeding (APR = 7.685 with 95% CI 1.502-39.309) were risk factors for malaria. On the other hand, higher education (APR = 0.104 with 95% CI 0.027-0.403), the use of mosquito repellent (APR = 0.138 with 95% CI 0.035-0.549), and the condition of house walls (APR = 0.145 with 95% CI 0.0414-0.511) were identified as protective factors. The current study highlights age and mosquito breeding sites as risk factors for malaria. Additionally, higher education, insect repellent use, and the condition of house walls are protective factors against malaria. Therefore, reducing risk factors and increasing protective measures through effective communication, information, and education are highly recommended to eliminate malaria in mining areas.
Collapse
Affiliation(s)
- Hamzah Hasyim
- Faculty of Public Health, Universitas Sriwijaya, Palembang, Indonesia.
- Faculty of Medicine, Institute for Occupational Medicine, Social Medicine and Environmental Medicine, Goethe University, Frankfurt Am Main, Germany.
| | - Wita Citra Dewi
- Faculty of Public Health, Universitas Sriwijaya, Palembang, Indonesia
| | | | - Rostika Flora
- Faculty of Public Health, Universitas Sriwijaya, Palembang, Indonesia
| | | | - Iche Andriyani Liberty
- Faculty of Medicine, Department of Public Health and Community Medicine, Universitas Sriwijaya, Palembang, Indonesia
| | - Heni Marini
- Faculty of Public Health, Universitas Sriwijaya, Palembang, Indonesia
| | - Ahmed Elagali
- School of Biological Sciences, The University of Western Australia, Perth, Australia
- Minderoo Foundation, Perth, Australia
| | - Siti Herlinda
- Faculty of Agriculture, Department of Plant Protection, Universitas Sriwijaya, Palembang, Indonesia
- Research Center for Sub-Optimal Lands (PUR-PLSO), Universitas Sriwijaya, Palembang, Indonesia
| | - Fadhilah Eka Maharani
- Faculty of Mathematics and Natural Sciences, Biology Department, Universitas Sriwijaya, Palembang, Indonesia
| |
Collapse
|
18
|
Kayendeke M, Nabirye C, Nayiga S, Westercamp N, Gonahasa S, Katureebe A, Kamya MR, Staedke SG, Hutchinson E. House modifications as a malaria control tool: how does local context shape participants' experience and interpretation in Uganda? Malar J 2023; 22:244. [PMID: 37626312 PMCID: PMC10463640 DOI: 10.1186/s12936-023-04669-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
BACKGROUND Evidence that house design can provide protection from malaria is growing. Housing modifications such as screening windows, doors, and ceilings, and attaching insecticide-impregnated materials to the eaves (the gap between the top of the wall and bottom of the roof), can protect against malaria. To be effective at scale, however, these modifications must be adopted by household residents. There is evidence that housing modifications can be acceptable, but in-depth knowledge on the experiences and interpretation of modifications is lacking. This qualitative study was carried out to provide a holistic account of the relationship between experiences and interpretations of four types of piloted housing modifications and the local context in Jinja, Uganda. METHODS Qualitative research was conducted between January to June 2021, before and during the installation of four types of housing modifications. The methods included nine weeks of participant observations in two study villages, nine focus group discussions with primary caregivers and heads of households (11-12 participants each), and nine key informant interviews with stakeholders and study team members. RESULTS Most residents supported the modifications. Experiences and interpretation of the housing modifications were shaped by the different types of housing in the area and the processes through which residents finished their houses, local forms of land and property ownership, and cultural and spiritual beliefs about houses. CONCLUSIONS To maximize the uptake and benefit of housing modifications against malaria, programme development needs to take local context into account. Forms of local land and house ownership, preferences, the social significance of housing types, and religious and spiritual ideas shape the responses to housing modifications in Jinja. These factors may be important in other setting. Trial registration Trial registration number is NCT04622241. The first draft was posted on November 9th 2020.
Collapse
Affiliation(s)
| | - Christine Nabirye
- Infectious Diseases Research Collaboration, Kampala, Uganda
- London School of Hygiene and Tropical Medicine, London, UK
| | - Susan Nayiga
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Nelli Westercamp
- Malaria Branch, Centers for Disease Control and Prevention, Atlanta, USA
| | | | | | - Moses R Kamya
- Infectious Diseases Research Collaboration, Kampala, Uganda
- Department of Medicine, Makerere University, Kampala, Uganda
| | | | | |
Collapse
|
19
|
Searle KM, Earland D, Francisco A, Muhiro V, Novela A, Ferrão J. Household structure is independently associated with malaria risk in rural Sussundenga, Mozambique. FRONTIERS IN EPIDEMIOLOGY 2023; 3:1137040. [PMID: 38455901 PMCID: PMC10911029 DOI: 10.3389/fepid.2023.1137040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 07/26/2023] [Indexed: 03/09/2024]
Abstract
Introduction Mozambique has the fourth highest malaria cases and malaria mortality globally. Locally, malaria incidence increases from low in the southern region to high in the central and northern regions. Manica Province in central Mozambique has the fourth highest prevalence of malaria out of the 11 provinces, and the highest in the central region of the country. In this area where coverage of interventions has been limited, household level risk factors can be important for understanding the natural history of infection, as well as the implementation of current and future interventions. There has been indication that the relationship between household structure and malaria risk is actually a mediating one between the true relationship between household income and education and Plasmodium falciparum infection. The objective of this study was to determine and quantify these complex relationships. Methods We conducted a community-based cross-sectional study in Sussundenga village. Sussundenga is a rural village, located in Sussundenga District, Manica Province, Mozambique. We enrolled 303 participants from 83 randomly selected households. We collected information on demographics, household construction, and administered a P. falciparum rapid diagnostic test (RDT). We constructed several generalized estimating equations logistic regression models to determine the independent effects of housing construction on malaria risk. We also constructed models separate from generalized estimating equations logistic mediation models to determine the proportion of effects mediated by household construction material in the relationship between head of household occupation and education and malaria risk. Results The overall malaria prevalence among the study population by RDT was 30.8%. In the multivariable model adjusting for all individual and household factors as potential confounders, rudimentary roof structure was the only household structural variable that was statistically significantly associated with increased malaria risk [OR 2.41 (1.03-5.63)]. We found no evidence that household structure mediated the relationship between head of household education or employment and malaria risk in our study population. Discussion Household structure was a significant risk factor for malaria infection in our study population. These findings are consistent with malaria being a disease of poverty and an area that could be targeted for future interventions that could have long-term impacts.
Collapse
Affiliation(s)
- Kelly M. Searle
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, United States
| | - Dominique Earland
- Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, United States
| | | | - Valy Muhiro
- Sussundenge-Sede Centro de Saude Rural, Sussundenga, Mozambique
| | - Anisío Novela
- Sussundenge-Sede Centro de Saude Rural, Sussundenga, Mozambique
| | - João Ferrão
- UniSCED Aberta de Mozambique, Chimoio, Mozambique
| |
Collapse
|
20
|
Hamre KES, Dismer AM, Rogier E, van den Hoogen LL, Williamson J, Kishore N, Travers A, McGee K, Pierre B, Fouché B, Impoinvil D, Holmes K, Stresman G, Druetz T, Eisele TP, Drakeley C, Lemoine JF, Chang MA. Spatial Clustering and Risk Factors for Malaria Infections and Marker of Recent Exposure to Plasmodium falciparum from a Household Survey in Artibonite, Haiti. Am J Trop Med Hyg 2023; 109:258-272. [PMID: 37277106 PMCID: PMC10397426 DOI: 10.4269/ajtmh.22-0599] [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: 09/13/2022] [Accepted: 04/12/2023] [Indexed: 06/07/2023] Open
Abstract
Targeting malaria interventions in elimination settings where transmission is heterogeneous is essential to ensure the efficient use of resources. Identifying the most important risk factors among persons experiencing a range of exposure can facilitate such targeting. A cross-sectional household survey was conducted in Artibonite, Haiti, to identify and characterize spatial clustering of malaria infections. Household members (N = 21,813) from 6,962 households were surveyed and tested for malaria. An infection was defined as testing positive for Plasmodium falciparum by either a conventional or novel highly sensitive rapid diagnostic test. Seropositivity to the early transcribed membrane protein 5 antigen 1 represented recent exposure to P. falciparum. Clusters were identified using SaTScan. Associations among individual, household, and environmental risk factors for malaria, recent exposure, and living in spatial clusters of these outcomes were evaluated. Malaria infection was detected in 161 individuals (median age: 15 years). Weighted malaria prevalence was low (0.56%; 95% CI: 0.45-0.70%). Serological evidence of recent exposure was detected in 1,134 individuals. Bed net use, household wealth, and elevation were protective, whereas being febrile, over age 5 years, and living in either households with rudimentary wall material or farther from the road increased the odds of malaria. Two predominant overlapping spatial clusters of infection and recent exposure were identified. Individual, household, and environmental risk factors are associated with the odds of individual risk and recent exposure in Artibonite; spatial clusters are primarily associated with household-level risk factors. Findings from serology testing can further strengthen the targeting of interventions.
Collapse
Affiliation(s)
- Karen E. S. Hamre
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
- CDC Foundation, Atlanta, Georgia
| | - Amber M. Dismer
- Emergency Response and Recovery Branch, Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Eric Rogier
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Lotus L. van den Hoogen
- London School of Hygiene & Tropical Medicine, London, United Kingdom
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - John Williamson
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Nishant Kishore
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
- CDC Foundation, Atlanta, Georgia
| | - Anyess Travers
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
- CDC Foundation, Atlanta, Georgia
| | - Kathleen McGee
- Population Services International/Organisation Haïtienne de Marketing Social pour la Santé, Peguy-ville, Haiti
| | - Baby Pierre
- Programme National de Contrôle de la Malaria, Ministère de la Santé Publique et de la Population, Port-au-Prince, Haiti
| | | | - Daniel Impoinvil
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Kathleen Holmes
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Gillian Stresman
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Thomas Druetz
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
- University of Montreal School of Public Health, Montreal, Canada
| | - Thomas P. Eisele
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Chris Drakeley
- London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Jean Frantz Lemoine
- Programme National de Contrôle de la Malaria, Ministère de la Santé Publique et de la Population, Port-au-Prince, Haiti
| | - Michelle A. Chang
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia
| |
Collapse
|
21
|
Wafula ST, Habermann T, Franke MA, May J, Puradiredja DI, Lorenz E, Brinkel J. What are the pathways between poverty and malaria in sub-Saharan Africa? A systematic review of mediation studies. Infect Dis Poverty 2023; 12:58. [PMID: 37291664 DOI: 10.1186/s40249-023-01110-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 05/29/2023] [Indexed: 06/10/2023] Open
Abstract
BACKGROUND Malaria remains a major burden in sub-Saharan Africa (SSA). While an association between poverty and malaria has been demonstrated, a clearer understanding of explicit mechanisms through which socioeconomic position (SEP) influences malaria risk is needed to guide the design of more comprehensive interventions for malaria risk mitigation. This systematic review provides an overview of the current evidence on the mediators of socioeconomic disparities in malaria in SSA. METHODS We searched PubMed and Web of Science for randomised controlled trials, cohort, case-control and cross-sectional studies published in English between January 1, 2000 to May 31, 2022. Further studies were identified following reviews of reference lists of the studies included. We included studies that either (1) conducted a formal mediation analysis of risk factors on the causal pathway between SEP and malaria infections or (2) adjusted for these potential mediators as confounders on the association between SEP and malaria using standard regression models. At least two independent reviewers appraised the studies, conducted data extraction, and assessed risk of bias. A systematic overview is presented for the included studies. RESULTS We identified 41 articles from 20 countries in SSA for inclusion in the final review. Of these, 30 studies used cross-sectional design, and 26 found socioeconomic inequalities in malaria risk. Three formal mediation analyses showed limited evidence of mediation of food security, housing quality, and previous antimalarial use. Housing, education, insecticide-treated nets, and nutrition were highlighted in the remaining studies as being protective against malaria independent of SEP, suggesting potential for mediation. However, methodological limitations included the use of cross-sectional data, insufficient confounder adjustment, heterogeneity in measuring both SEP and malaria, and generally low or moderate-quality studies. No studies considered exposure mediator interactions or considered identifiability assumptions. CONCLUSIONS Few studies have conducted formal mediation analyses to elucidate pathways between SEP and malaria. Findings indicate that food security and housing could be more feasible (structural) intervention targets. Further research using well-designed longitudinal studies and improved analysis would illuminate the current sparse evidence into the pathways between SEP and malaria and adduce evidence for more potential targets for effective intervention.
Collapse
Affiliation(s)
- Solomon T Wafula
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
- Department of Disease Control and Environmental Health, School of Public Health, Makerere University, Kampala, Uganda.
| | - Theresa Habermann
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Mara Anna Franke
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- Charité Global Health, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen May
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lubeck-Riems, Hamburg, Germany
- Department of Tropical Medicine, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Dewi Ismajani Puradiredja
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Eva Lorenz
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lubeck-Riems, Hamburg, Germany
- Institute of Medical Biostatistics, Epidemiology and Informatics, University Centre of the Johannes Gutenberg University, Mainz, Germany
| | - Johanna Brinkel
- Department of Infectious Disease Epidemiology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lubeck-Riems, Hamburg, Germany
| |
Collapse
|
22
|
Armando CJ, Rocklöv J, Sidat M, Tozan Y, Mavume AF, Bunker A, Sewes MO. Climate variability, socio-economic conditions and vulnerability to malaria infections in Mozambique 2016-2018: a spatial temporal analysis. Front Public Health 2023; 11:1162535. [PMID: 37325319 PMCID: PMC10267345 DOI: 10.3389/fpubh.2023.1162535] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 04/28/2023] [Indexed: 06/17/2023] Open
Abstract
Background Temperature, precipitation, relative humidity (RH), and Normalized Different Vegetation Index (NDVI), influence malaria transmission dynamics. However, an understanding of interactions between socioeconomic indicators, environmental factors and malaria incidence can help design interventions to alleviate the high burden of malaria infections on vulnerable populations. Our study thus aimed to investigate the socioeconomic and climatological factors influencing spatial and temporal variability of malaria infections in Mozambique. Methods We used monthly malaria cases from 2016 to 2018 at the district level. We developed an hierarchical spatial-temporal model in a Bayesian framework. Monthly malaria cases were assumed to follow a negative binomial distribution. We used integrated nested Laplace approximation (INLA) in R for Bayesian inference and distributed lag nonlinear modeling (DLNM) framework to explore exposure-response relationships between climate variables and risk of malaria infection in Mozambique, while adjusting for socioeconomic factors. Results A total of 19,948,295 malaria cases were reported between 2016 and 2018 in Mozambique. Malaria risk increased with higher monthly mean temperatures between 20 and 29°C, at mean temperature of 25°C, the risk of malaria was 3.45 times higher (RR 3.45 [95%CI: 2.37-5.03]). Malaria risk was greatest for NDVI above 0.22. The risk of malaria was 1.34 times higher (1.34 [1.01-1.79]) at monthly RH of 55%. Malaria risk reduced by 26.1%, for total monthly precipitation of 480 mm (0.739 [95%CI: 0.61-0.90]) at lag 2 months, while for lower total monthly precipitation of 10 mm, the risk of malaria was 1.87 times higher (1.87 [1.30-2.69]). After adjusting for climate variables, having lower level of education significantly increased malaria risk (1.034 [1.014-1.054]) and having electricity (0.979 [0.967-0.992]) and sharing toilet facilities (0.957 [0.924-0.991]) significantly reduced malaria risk. Conclusion Our current study identified lag patterns and association between climate variables and malaria incidence in Mozambique. Extremes in climate variables were associated with an increased risk of malaria transmission, peaks in transmission were varied. Our findings provide insights for designing early warning, prevention, and control strategies to minimize seasonal malaria surges and associated infections in Mozambique a region where Malaria causes substantial burden from illness and deaths.
Collapse
Affiliation(s)
- Chaibo Jose Armando
- Department of Public Health and Clinical Medicine, Sustainable Health Section, Umeå University, Umeå, Sweden
| | - Joacim Rocklöv
- Department of Public Health and Clinical Medicine, Sustainable Health Section, Umeå University, Umeå, Sweden
- Heidelberg Institute of Global Health and Interdisciplinary Centre for Scientific Computing, Heidelberg University, Heidelberg, Germany
| | - Mohsin Sidat
- Faculty of Medicine, Eduardo Mondlane University, Maputo, Mozambique
| | - Yesim Tozan
- School of Global Public Health, New York University, New York, NY, United States
| | | | - Aditi Bunker
- Center for Climate, Health, and the Global Environment, Harvard T.H. Chan School of Public Health, Boston, MA, United States
- Heidelberg Institute of Global Health, University of Heidelberg, Heidelberg, Germany
| | - Maquins Odhiambo Sewes
- Department of Public Health and Clinical Medicine, Sustainable Health Section, Umeå University, Umeå, Sweden
- Heidelberg Institute of Global Health, University of Heidelberg, Heidelberg, Germany
| |
Collapse
|
23
|
Oumbouke WA, Barreaux AMG, Zran IT, Koffi AA, N'Guessan Y, Alou LPA, Wolie RZ, Cook J, Sternberg ED, Thomas MB, N'Guessan R. Exploring alternative insecticide delivery options in a "lethal house lure" for malaria vector control. Sci Rep 2023; 13:4820. [PMID: 36964136 PMCID: PMC10039065 DOI: 10.1038/s41598-023-31116-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 03/07/2023] [Indexed: 03/26/2023] Open
Abstract
The In2Care EaveTube is a house modification designed to block and kill malaria mosquitoes using an electrostatic netting treated with insecticide powder. A previous study demonstrated prolonged duration of effective action of insecticide-treated electrostatic netting in a semi-field setting. As part of a cluster randomized controlled trial (CRT) of the EaveTube intervention in Côte d'Ivoire, we investigated the residual efficacy of a pyrethroid insecticide deployed in EaveTubes under village conditions of use. We also explored the scope of using existing malaria control technologies including LLINs and IRS as alternative methods to deliver insecticides in the lethal house lure. The efficacy of beta-cyfluthrin was monitored over time using the "eave tube bioassay" method. Mortality of beta-cyfluthrin exposed pyrethroid resistant Anopheles gambiae mosquitoes was > 80% after 4 months. The impact (mosquito mortality) of PVC tubes coated with pirimiphos methyl was similar to that of beta-cyfluthrin treated insert (66.8 vs. 62.8%) in release-recapture experiments in experimental huts. Efficacy was significantly lower with all the LLINs tested; however, the roof of PermaNet 3.0 induced significantly higher mosquito mortality (50.4%) compared to Olyset Plus (25.9%) and Interceptor G2 (21.6%) LLINs. The efficacy of the alternative delivery methods was short-lived with mortality decreasing below 50% within 2 months in residual activity bioassays. None of the products tested appeared superior to the powder treatments. Further research is therefore required to identify suitable insecticide delivery options in EaveTube for malaria vector control.
Collapse
Affiliation(s)
- Welbeck A Oumbouke
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK.
- Innovative Vector Control Consortium, IVCC, Liverpool, UK.
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire.
| | - Antoine M G Barreaux
- Department of Entomology, Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, 16802, USA
- Animal Health Theme, ICIPE, Nairobi, Kenya
- CIRAD, UMR INTERTRYP, 34398, Montpellier, France
- CIRAD, IRD, INTERTRYP, Univ Montpellier, 34000, Montpellier, France
| | - Innocent T Zran
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Alphonsine A Koffi
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Yao N'Guessan
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Ludovic P Ahoua Alou
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire
| | - Rosine Z Wolie
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire
- Unité de Recherche et de Pédagogie de Génétique, UFR Biosciences, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
| | - Jackie Cook
- Medical Research Council (MRC) International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - Eleanore D Sternberg
- Department of Entomology, Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, 16802, USA
- Tropical Health LLP, London, UK
| | - Matthew B Thomas
- Department of Entomology, Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, 16802, USA
- Entomology and Nematology Department, University of Florida, Gainesville, USA
| | - Raphael N'Guessan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK
- Institut Pierre Richet (IPR)/Institut National de Santé Publique (INSP), Bouaké, Côte d'Ivoire
| |
Collapse
|
24
|
Musoke D, Atusingwize E, Namata C, Ndejjo R, Wanyenze RK, Kamya MR. Integrated malaria prevention in low- and middle-income countries: a systematic review. Malar J 2023; 22:79. [PMID: 36879237 PMCID: PMC9987134 DOI: 10.1186/s12936-023-04500-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 02/16/2023] [Indexed: 03/08/2023] Open
Abstract
BACKGROUND As many countries aim to eliminate malaria, use of comprehensive approaches targeting the mosquito vector and environment are needed. Integrated malaria prevention advocates the use of several malaria prevention measures holistically at households and in the community. The aim of this systematic review was to collate and summarize the impact of integrated malaria prevention in low- and middle-income countries on malaria burden. METHODS Literature on integrated malaria prevention, defined as the use of two or more malaria prevention methods holistically, was searched from 1st January 2001 to 31st July 2021. The primary outcome variables were malaria incidence and prevalence, while the secondary outcome measures were human biting and entomological inoculation rates, and mosquito mortality. RESULTS A total of 10,931 studies were identified by the search strategy. After screening, 57 articles were included in the review. Studies included cluster randomized controlled trials, longitudinal studies, programme evaluations, experimental hut/houses, and field trials. Various interventions were used, mainly combinations of two or three malaria prevention methods including insecticide-treated nets (ITNs), indoor residual spraying (IRS), topical repellents, insecticide sprays, microbial larvicides, and house improvements including screening, insecticide-treated wall hangings, and screening of eaves. The most common methods used in integrated malaria prevention were ITNs and IRS, followed by ITNs and topical repellents. There was reduced incidence and prevalence of malaria when multiple malaria prevention methods were used compared to single methods. Mosquito human biting and entomological inoculation rates were significantly reduced, and mosquito mortality increased in use of multiple methods compared to single interventions. However, a few studies showed mixed results or no benefits of using multiple methods to prevent malaria. CONCLUSION Use of multiple malaria prevention methods was effective in reducing malaria infection and mosquito density in comparison with single methods. Results from this systematic review can be used to inform future research, practice, policy and programming for malaria control in endemic countries.
Collapse
Affiliation(s)
- David Musoke
- Department of Disease Control and Environmental Health, School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda.
| | - Edwinah Atusingwize
- Department of Disease Control and Environmental Health, School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda
| | - Carol Namata
- Department of Disease Control and Environmental Health, School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda
| | - Rawlance Ndejjo
- Department of Disease Control and Environmental Health, School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda
| | - Rhoda K Wanyenze
- Department of Disease Control and Environmental Health, School of Public Health, Makerere University College of Health Sciences, Kampala, Uganda
| | - Moses R Kamya
- Department of Medicine, School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| |
Collapse
|
25
|
Chisanga B, Bulte E, Kassie M, Mutero C, Masaninga F, Sangoro OP. The economic impacts of house screening against malaria transmission: Experimental evidence from eastern Zambia. Soc Sci Med 2023; 321:115778. [PMID: 36827904 DOI: 10.1016/j.socscimed.2023.115778] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/21/2023]
Abstract
Malaria imposes an economic burden for human populations in many African countries, and this burden may be reduced through house screening initiatives. We use a randomized controlled trial to measure the economic impacts of house screening against malaria infection. We use a sample of 800 households from 89 villages in rural and peri-urban Zambia to collect baseline data in August 2019 and endline data in August 2020. The main outcome variables are (self-reported) malaria prevalence rates, labor supply, and income, and consider individual and household-level outcomes. House screening reduces malaria prevalence, the number of sick days due to malaria, and the number of malaria episodes. Impacts on adults are more pronounced than on children. In terms of economic impacts, house screening increases labor supply and (household) income. We find particularly large effects on labor supply for women household members. A cost-benefit analysis, based on estimated benefits and measured costs, suggests that the private benefits of house screening exceed the costs. While not all houses are suitable for house screening, we conclude that screening is a promising and cost-effective approach to reduce malaria infections.
Collapse
Affiliation(s)
- Brian Chisanga
- Development Economics Group, Wageningen University, the Netherlands.
| | - Erwin Bulte
- Development Economics Group, Wageningen University, the Netherlands.
| | - Menale Kassie
- International Centre of Insect Physiology and Ecology (ICIPE), Kenya.
| | - Clifford Mutero
- International Centre of Insect Physiology and Ecology (ICIPE), Kenya.
| | | | | |
Collapse
|
26
|
García GA, Janko M, Hergott DEB, Donfack OT, Smith JM, Mba Eyono JN, DeBoer KR, Nguema Avue RM, Phiri WP, Aldrich EM, Schwabe C, Stabler TC, Rivas MR, Cameron E, Guerra CA, Cook J, Kleinschmidt I, Bradley J. Identifying individual, household and environmental risk factors for malaria infection on Bioko Island to inform interventions. Malar J 2023; 22:72. [PMID: 36859263 PMCID: PMC9979414 DOI: 10.1186/s12936-023-04504-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 02/18/2023] [Indexed: 03/03/2023] Open
Abstract
BACKGROUND Since 2004, malaria transmission on Bioko Island has declined significantly as a result of the scaling-up of control interventions. The aim of eliminating malaria from the Island remains elusive, however, underscoring the need to adapt control to the local context. Understanding the factors driving the risk of malaria infection is critical to inform optimal suits of interventions in this adaptive approach. METHODS This study used individual and household-level data from the 2015 and 2018 annual malaria indicator surveys on Bioko Island, as well as remotely-sensed environmental data in multilevel logistic regression models to quantify the odds of malaria infection. The analyses were stratified by urban and rural settings and by survey year. RESULTS Malaria prevalence was higher in 10-14-year-old children and similar between female and male individuals. After adjusting for demographic factors and other covariates, many of the variables investigated showed no significant association with malaria infection. The factor most strongly associated was history of travel to mainland Equatorial Guinea (mEG), which increased the odds significantly both in urban and rural settings (people who travelled had 4 times the odds of infection). Sleeping under a long-lasting insecticidal net decreased significantly the odds of malaria across urban and rural settings and survey years (net users had around 30% less odds of infection), highlighting their contribution to malaria control on the Island. Improved housing conditions indicated some protection, though this was not consistent across settings and survey year. CONCLUSIONS Malaria risk on Bioko Island is heterogeneous and determined by a combination of factors interacting with local mosquito ecology. These interactions grant further investigation in order to better adapt control according to need. The single most important risk factor identified was travel to mEG, in line with previous investigations, and represents a great challenge for the success of malaria control on the Island.
Collapse
Affiliation(s)
| | - Mark Janko
- Duke Global Health Institute, Duke University, Durham, NC, USA
| | - Dianna E B Hergott
- Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA, USA
| | | | | | | | | | | | - Wonder P Phiri
- MCD Global Health, Bioko Island, Malabo, Equatorial Guinea
| | | | | | - Thomas C Stabler
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Matilde Riloha Rivas
- Equatorial Guinea Ministry of Health and Social Welfare, Bioko Island, Malabo, Equatorial Guinea
| | - Ewan Cameron
- Telethon Kids Institute, Perth Children's Hospital, Perth, Australia
| | | | - Jackie Cook
- MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - Immo Kleinschmidt
- MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
- School of Pathology, Faculty of Health Science, Wits Institute for Malaria Research, University of Witwatersrand, Johannesburg, South Africa
| | - John Bradley
- MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| |
Collapse
|
27
|
Bofu RM, Santos EM, Msugupakulya BJ, Kahamba NF, Swilla JD, Njalambaha R, Kelly AH, Lezaun J, Christofides N, Okumu FO, Finda MF. The needs and opportunities for housing improvement for malaria control in southern Tanzania. Malar J 2023; 22:69. [PMID: 36849883 PMCID: PMC9972788 DOI: 10.1186/s12936-023-04499-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 02/16/2023] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND Malaria disproportionately affects low-income households in rural communities where poor housing is common. Despite evidence that well-constructed and mosquito-proofed houses can reduce malaria risk, housing improvement is rarely included in malaria control toolboxes. This study assessed the need, magnitude, and opportunities for housing improvement to control malaria in rural Tanzania. METHODS A mixed-methods study was conducted in 19 villages across four district councils in southern Tanzania. A structured survey was administered to 1292 community members to assess need, perceptions, and opportunities for housing improvement for malaria control. Direct observations of 802 houses and surrounding environments were done to identify the actual needs and opportunities, and to validate the survey findings. A market survey was done to assess availability and cost of resources and services necessary for mosquito-proofing homes. Focus group discussions were conducted with key stakeholders to explore insights on the potential and challenges of housing improvement as a malaria intervention. RESULTS Compared to other methods for malaria control, housing improvement was among the best understood and most preferred by community members. Of the 735 survey respondents who needed housing improvements, a majority needed window screening (91.1%), repairs of holes in walls (79.4%), door covers (41.6%), closing of eave spaces (31.2%) and better roofs (19.0%). Community members invested significant efforts to improve their own homes against malaria and other dangers, but these efforts were often slow and delayed due to high costs and limited household incomes. Study participants suggested several mechanisms of support to improve their homes, including government loans and subsidies. CONCLUSION Addressing the need for housing improvement is a critical component of malaria control efforts in southern Tanzania. In this study, a majority of the community members surveyed needed modest modifications and had plans to work on those modifications. Without additional support, their efforts were however generally slow; households would take years to sufficiently mosquito-proof their houses. It is, therefore, crucial to bring together the key players across sectors to reduce barriers in malaria-proofing housing in endemic settings. These may include government subsidies or partnerships with businesses to make housing improvement more accessible and affordable to residents.
Collapse
Affiliation(s)
- Ramadhani M Bofu
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania.
- School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania.
- Mpwapwa Institute of Health and Allied Sciences, The Ministry of Health, P.O. Box 743, Dodoma, Tanzania.
| | - Ellen M Santos
- Department of Applied Health, Southern Illinois University Edwardsville, Edwardsville, USA
| | - Betwel J Msugupakulya
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Najat F Kahamba
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G128QQ, UK
| | - Joseph D Swilla
- School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
- Department of Molecular Biology and Biotechnology, University of Dar es Salaam, Dar es Salaam, Tanzania
| | - Rukiyah Njalambaha
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
| | - Ann H Kelly
- Department of Global Health and Social Medicine, King's College London, London, UK
| | - Javier Lezaun
- Institute for Science, Innovation, and Society, School of Anthropology and Museum Ethnography, University of Oxford, Oxford, UK
| | - Nicola Christofides
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, Johannesburg, 2000, South Africa
| | - Fredros O Okumu
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
- School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G128QQ, UK
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, 1 Smuts Avenue, Braamfontein, Johannesburg, 2000, South Africa
| | - Marceline F Finda
- Department of Environmental Health and Ecological Sciences, Ifakara Health Institute, P. O. Box 53, Ifakara, Tanzania
- School of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology, P. O. Box 447, Arusha, Tanzania
| |
Collapse
|
28
|
Hauser M, Kabuya JBB, Mantus M, Kamavu LK, Sichivula JL, Matende WM, Fritschi N, Shields T, Curriero F, Kvit A, Chongwe G, Moss WJ, Ritz N, Ippolito MM. Malaria in Refugee Children Resettled to a Holoendemic Area of Sub-Saharan Africa. Clin Infect Dis 2023; 76:e1104-e1113. [PMID: 35640824 PMCID: PMC10169438 DOI: 10.1093/cid/ciac417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 05/06/2022] [Accepted: 05/20/2022] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Malaria is a leading cause of morbidity and mortality in refugee children in high-transmission parts of Africa. Characterizing the clinical features of malaria in refugees can inform approaches to reduce its burden. METHODS The study was conducted in a high-transmission region of northern Zambia hosting Congolese refugees. We analyzed surveillance data and hospital records of children with severe malaria from refugee and local sites using multivariable regression models and geospatial visualization. RESULTS Malaria prevalence in the refugee settlement was similar to the highest burden areas in the district, consistent with the local ecology and leading to frequent rapid diagnostic test stockouts. We identified 2197 children hospitalized for severe malaria during the refugee crisis in 2017 and 2018. Refugee children referred from a refugee transit center (n = 63) experienced similar in-hospital mortality to local children and presented with less advanced infection. However, refugee children from a permanent refugee settlement (n = 110) had more than double the mortality of local children (P < .001), had lower referral rates, and presented more frequently with advanced infection and malnutrition. Distance from the hospital was an important mediator of the association between refugee status and mortality but did not account for all of the increased risk. CONCLUSIONS Malaria outcomes were more favorable in refugee children referred from a highly outfitted refugee transit center than those referred later from a permanent refugee settlement. Refugee children experienced higher in-hospital malaria mortality due in part to delayed presentation and higher rates of malnutrition. Interventions tailored to the refugee context are required to ensure capacity for rapid diagnosis and referral to reduce malaria mortality.
Collapse
Affiliation(s)
- Manuela Hauser
- Faculty of Medicine, University of Basel, Basel, Switzerland.,Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Jean-Bertin B Kabuya
- Department of Clinical Sciences, Tropical Diseases Research Centre, Ndola, Zambia
| | - Molly Mantus
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Luc K Kamavu
- Office of Hospital Administration, Saint Paul's General Hospital, Nchelenge, Zambia
| | - James L Sichivula
- Department of Clinical Sciences, Tropical Diseases Research Centre, Ndola, Zambia
| | - Wycliffe M Matende
- United Nations High Commissioner for Refugees, Country Representation Office, Lusaka, Zambia
| | - Nora Fritschi
- Mycobacterial and Migrant Health Research Group, University of Basel Children's Hospital, Basel, Switzerland.,Department of Clinical Research, University of Basel, Basel, Switzerland
| | - Timothy Shields
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Frank Curriero
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Anton Kvit
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Gershom Chongwe
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - William J Moss
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.,Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Nicole Ritz
- Mycobacterial and Migrant Health Research Group, University of Basel Children's Hospital, Basel, Switzerland.,Infectious Disease and Vaccinology Unit, University Children's Hospital Basel, University of Basel, Basel, Switzerland.,Department of Pediatrics, The Royal Children's Hospital Melbourne, The University of Melbourne, Melbourne, Australia.,Department of Paediatrics and Paediatric Infectious Diseases, Children's Hospital, Lucerne Cantonal Hospital, Lucerne, Switzerland
| | - Matthew M Ippolito
- Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.,Division of Clinical Pharmacology and Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
29
|
Echodu DC, Yeka A, Eganyu T, Odude W, Bukenya F, Amoah B, Wanzira H, Colborn K, Elliott RC, Powell SE, Kilama M, Mulebeke R, Nankabirwa J, Giorgi E, Roskosky M, Omoding O, Gonahasa S, Opigo J. Impact of population based indoor residual spraying with and without mass drug administration with dihydroartemisinin-piperaquine on malaria prevalence in a high transmission setting: a quasi-experimental controlled before-and-after trial in northeastern Uganda. BMC Infect Dis 2023; 23:72. [PMID: 36747133 PMCID: PMC9901833 DOI: 10.1186/s12879-023-07991-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 01/06/2023] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Declines in malaria burden in Uganda have slowed. Modelling predicts that indoor residual spraying (IRS) and mass drug administration (MDA), when co-timed, have synergistic impact. This study investigated additional protective impact of population-based MDA on malaria prevalence, if any, when added to IRS, as compared with IRS alone and with standard of care (SOC). METHODS The 32-month quasi-experimental controlled before-and-after trial enrolled an open cohort of residents (46,765 individuals, 1st enumeration and 52,133, 4th enumeration) of Katakwi District in northeastern Uganda. Consented participants were assigned to three arms based on residential subcounty at study start: MDA+IRS, IRS, SOC. IRS with pirimiphos methyl and MDA with dihydroartemisinin- piperaquine were delivered in 4 co-timed campaign-style rounds 8 months apart. The primary endpoint was population prevalence of malaria, estimated by 6 cross-sectional surveys, starting at baseline and preceding each subsequent round. RESULTS Comparing malaria prevalence in MDA+IRS and IRS only arms over all 6 surveys (intention-to-treat analysis), roughly every 6 months post-interventions, a geostatistical model found a significant additional 15.5% (95% confidence interval (CI): [13.7%, 17.5%], Z = 9.6, p = 5e-20) decrease in the adjusted odds ratio (aOR) due to MDA for all ages, a 13.3% reduction in under 5's (95% CI: [10.5%, 16.8%], Z = 4.02, p = 5e-5), and a 10.1% reduction in children 5-15 (95% CI: [8.5%, 11.8%], Z = 4.7, p = 2e-5). All ages residents of the MDA + IRS arm enjoyed an overall 80.1% reduction (95% CI: [80.0%, 83.0%], p = 0.0001) in odds of qPCR confirmed malaria compared with SOC residents. Secondary difference-in-difference analyses comparing surveys at different timepoints to baseline showed aOR (MDA + IRS vs IRS) of qPCR positivity between 0.28 and 0.66 (p < 0.001). Of three serious adverse events, one (nonfatal) was considered related to study medications. Limitations include the initial non-random assignment of study arms, the single large cluster per arm, and the lack of an MDA-only arm, considered to violate equipoise. CONCLUSIONS Despite being assessed at long time points 5-7 months post-round, MDA plus IRS provided significant additional protection from malaria infection over IRS alone. Randomized trials of MDA in large areas undergoing IRS recommended as well as cohort studies of impact on incidence. TRIAL REGISTRATION This trial was retrospectively registered 11/07/2018 with the Pan African Clinical Trials Registry (PACTR201807166695568).
Collapse
Affiliation(s)
| | - Adoke Yeka
- grid.11194.3c0000 0004 0620 0548Makerere University College of Health Sciences, School of Public Health, P.O. Box 7072, Kampala, Uganda
| | - Thomas Eganyu
- Pilgrim Africa, Plot 8 Engwau Road, PO Box 577, Soroti, Uganda
| | - Wycliff Odude
- Pilgrim Africa, Plot 8 Engwau Road, PO Box 577, Soroti, Uganda
| | - Fred Bukenya
- Pilgrim Africa, Plot 8 Engwau Road, PO Box 577, Soroti, Uganda
| | - Benjamin Amoah
- grid.7445.20000 0001 2113 8111School of Public Health, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London, SW7 2AZ UK
| | | | - Kathryn Colborn
- grid.430503.10000 0001 0703 675XUniversity of Colorado Anschutz Medical Campus, 12631 East 17th Avenue, Aurora, CO 80045 USA
| | - Richard C. Elliott
- Pilgrim Africa, 8001 14th Avenue NE, Suite A, Seattle, WA 98115 USA ,grid.184764.80000 0001 0670 228XMicron School of Materials Science and Engineering, Boise State University, Engineering Building, Suite 338, Boise, ID 83725 USA
| | | | - Maxwell Kilama
- Pilgrim Africa, Plot 8 Engwau Road, PO Box 577, Soroti, Uganda
| | - Ronald Mulebeke
- grid.11194.3c0000 0004 0620 0548Makerere University College of Health Sciences, School of Public Health, P.O. Box 7072, Kampala, Uganda
| | - Joaniter Nankabirwa
- grid.463352.50000 0004 8340 3103Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Emanuele Giorgi
- grid.9835.70000 0000 8190 6402Lancaster University Medical School, Centre for Health Informatics, Computing and Statistics, Lancaster, UK
| | - Mellisa Roskosky
- Pilgrim Africa, 8001 14th Avenue NE, Suite A, Seattle, WA 98115 USA ,grid.21107.350000 0001 2171 9311Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
| | - Osborn Omoding
- Pilgrim Africa, Plot 8 Engwau Road, PO Box 577, Soroti, Uganda
| | - Samuel Gonahasa
- grid.463352.50000 0004 8340 3103Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Jimmy Opigo
- grid.415705.2National Malaria Control Division, Ministry of Health Uganda, Kampala, Uganda
| |
Collapse
|
30
|
Mmbando AS, Mponzi WP, Ngowo HS, Kifungo K, Kasubiri R, Njalambaha RM, Gavana T, Eiras AE, Batista EPA, Finda MF, Sangoro OP, Okumu FO. Small-scale field evaluation of transfluthrin-treated eave ribbons and sandals for the control of malaria vectors in rural Tanzania. Malar J 2023; 22:43. [PMID: 36739391 PMCID: PMC9898903 DOI: 10.1186/s12936-023-04476-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 02/01/2023] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Early-evening and outdoor-biting mosquitoes may compromise the effectiveness of frontline malaria interventions, notably insecticide-treated nets (ITNs). This study aimed to evaluate the efficacy of low-cost insecticide-treated eave ribbons and sandals as supplementary interventions against indoor-biting and outdoor-biting mosquitoes in south-eastern Tanzania, where ITNs are already widely used. METHODS This study was conducted in three villages, with 72 households participating (24 households per village). The households were divided into four study arms and assigned: transfluthrin-treated sandals (TS), transfluthrin-treated eave ribbons (TER), a combination of TER and TS, or experimental controls. Each arm had 18 households, and all households received new ITNs. Mosquitoes were collected using double net traps (to assess outdoor biting), CDC light traps (to assess indoor biting), and Prokopack aspirators (to assess indoor resting). Protection provided by the interventions was evaluated by comparing mosquito densities between the treatment and control arms. Additional tests were done in experimental huts to assess the mortality of wild mosquitoes exposed to the treatments or controls. RESULTS TERs reduced indoor-biting, indoor-resting and outdoor-biting Anopheles arabiensis by 60%, 73% and 41%, respectively, while TS reduced the densities by 18%, 40% and 42%, respectively. When used together, TER & TS reduced indoor-biting, indoor-resting and outdoor-biting An. arabiensis by 53%, 67% and 57%, respectively. Protection against Anopheles funestus ranged from 42 to 69% with TER and from 57 to 74% with TER & TS combined. Mortality of field-collected mosquitoes exposed to TER, TS or both interventions was 56-78% for An. arabiensis and 47-74% for An. funestus. CONCLUSION Transfluthrin-treated eave ribbons and sandals or their combination can offer significant household-level protection against malaria vectors. Their efficacy is magnified by the transfluthrin-induced mortality, which was observed despite the prevailing pyrethroid resistance in the study area. These results suggest that TER and TS could be useful supplementary tools against residual malaria transmission in areas where ITN coverage is high but additional protection is needed against early-evening and outdoor-biting mosquitoes. Further research is needed to validate the performance of these tools in different settings, and assess their long-term effectiveness and feasibility for malaria control.
Collapse
Affiliation(s)
- Arnold S Mmbando
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania.
| | - Winifrida P Mponzi
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
| | - Halfan S Ngowo
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Khamis Kifungo
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
| | - Robert Kasubiri
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
| | - Rukiyah M Njalambaha
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
| | - Tegemeo Gavana
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
| | - Alvaro E Eiras
- Laboratory of Technological Innovation of Vector Control, Department of Parasitology, Biological Science Institute, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Elis P A Batista
- Laboratory of Technological Innovation of Vector Control, Department of Parasitology, Biological Science Institute, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Marceline F Finda
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Republic of South Africa
| | - Onyango P Sangoro
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania
- Human Health Theme, International Centre of Insect Physiology and Ecology (ICIPE), Nairobi City, Kenya
| | - Fredros O Okumu
- Environmental Health and Ecological Sciences, Ifakara Health Institute, Ifakara, Tanzania.
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Republic of South Africa.
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK.
- School of Life Science and Bioengineering, Nelson Mandela African Institution of Science & Technology, Arusha, Tanzania.
| |
Collapse
|
31
|
Abong’o B, Gimnig JE, Omoke D, Ochomo E, Walker ED. Screening eaves of houses reduces indoor mosquito density in rural, western Kenya. Malar J 2022; 21:377. [PMID: 36494664 PMCID: PMC9733111 DOI: 10.1186/s12936-022-04397-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Despite the scale-up of insecticide-treated nets and indoor residual spraying, the bulk of malaria transmission in western Kenya still occurs indoors, late at night. House improvement is a potential long-term solution to further reduce malaria transmission in the region. METHODS The impact of eave screening on mosquito densities was evaluated in two rural villages in western Kenya. One-hundred-and-twenty pairs of structurally similar, neighbouring houses were used in the study. In each pair, one house was randomly selected to receive eave screening at the beginning of the study while the other remained unscreened until the end of the sampling period. Mosquito sampling was performed monthly by motorized aspiration method for 4 months. The collected mosquitoes were analysed for species identification. RESULTS Compared to unscreened houses, significantly fewer female Anopheles funestus (RR = 0.40, 95% CI 0.29-0.55), Anopheles gambiae Complex (RR = 0.46, 95% CI 0.34-0.62) and Culex species (RR = 0.53, 95% CI 0.45-0.61) were collected in screened houses. No significant differences in the densities of the mosquitoes were detected in outdoor collections. Significantly fewer Anopheles funestus were collected indoors from houses with painted walls (RR = 0.05, 95% CI 0.01-0.38) while cooking in the house was associated with significantly lower numbers of Anopheles gambiae Complex indoors (RR = 0.60, 95% CI 0.45-0.79). Nearly all house owners (99.6%) wanted their houses permanently screened, including 97.7% that indicated a willingness to use their own resources. However, 99.2% required training on house screening. The cost of screening a single house was estimated at KES6,162.38 (US$61.62). CONCLUSION Simple house modification by eave screening has the potential to reduce the indoor occurrence of both Anopheles and Culex mosquito species. Community acceptance was very high although education and mobilization may be needed for community uptake of house modification for vector control. Intersectoral collaboration and favourable government policies on housing are important links towards the adoption of house improvements for malaria control.
Collapse
Affiliation(s)
- Bernard Abong’o
- grid.33058.3d0000 0001 0155 5938Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - John E. Gimnig
- grid.416738.f0000 0001 2163 0069Centers for Disease Control and Prevention, Division of Parasitic Diseases, Atlanta, GA 30341 USA
| | - Diana Omoke
- grid.33058.3d0000 0001 0155 5938Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Eric Ochomo
- grid.33058.3d0000 0001 0155 5938Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Edward D. Walker
- grid.17088.360000 0001 2150 1785Michigan State University, 6169 Biomedical Physical Sciences Building, East Lansing, MI 48824 USA
| |
Collapse
|
32
|
Msoffe R, Hewitt M, Masalu JP, Finda M, Kavishe DR, Okumu FO, Mpolya EA, Kaindoa EW, Killeen GF. Participatory development of practical, affordable, insecticide-treated mosquito proofing for a range of housing designs in rural southern Tanzania. Malar J 2022; 21:318. [PMCID: PMC9636681 DOI: 10.1186/s12936-022-04333-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 10/18/2022] [Indexed: 11/08/2022] Open
Abstract
Abstract
Background
Insecticidal mosquito-proof netting screens could combine the best features of insecticide-treated nets (ITNs) and indoor residual spraying (IRS), the two most important front line vector control interventions in Africa today, and also overcome the most important limitations of these methods. This study engaged members of a rural Tanzanian community in developing and evaluating simple, affordable and scalable procedures for installing readily available screening materials on eave gaps and windows of their own houses, and then treating those screens with a widely used IRS formulation of the organophosphate insecticide pirimiphos-methyl (PM).
Methods
A cohort of 54 households recruited upon consent, following which the structural features and occupant demographics of their houses were surveyed. Indoor mosquito densities were surveyed longitudinally, for approximately 3 months before and over 5 months after participatory house modification and screening using locally available materials. Each house was randomly assigned to one of three study arms: (1) No screens installed until the end of the study (negative control), (2) untreated screens installed, and (3) screened installed and then treated with PM, the insecticidal activity of which was subsequently assessed using standard cone assays.
Results
Almost all (52) recruited households participated until the end, at which point all houses had been successfully screened. In most cases, screening was only installed after making enabling structural modifications that were accepted by the enrolled households. Compared to unscreened houses, houses with either treated or untreated screens both almost entirely excluded Anopheles arabiensis (Relative reduction (RR) ≥ 98%, P < < 0.0001), the most abundant local malaria vector. However, screens were far less effective against Culex quinquefasciatus (RR ≤ 46%, P < < 0.0001), a non-malaria vector causing considerable biting nuisance, regardless of their treatment status. While PM did not augment household level protection by screens against either mosquito species (P = 0.676 and 0.831, respectively), 8 months after treatment it still caused 73% and 89% mortality among susceptible insectary-reared Anopheles gambiae following exposures of 3 and 30 min, respectively.
Conclusions
Participatory approaches to mosquito proofing houses may be acceptable and effective, and installed screens may be suitable targets for residual insecticide treatments.
Collapse
|
33
|
Wesolowski A, Ippolito MM, Gebhardt ME, Ferriss E, Schue JL, Kobayashi T, Chaponda M, Kabuya JB, Muleba M, Mburu M, Matoba J, Musonda M, Katowa B, Lubinda M, Hamapumbu H, Simubali L, Mudenda T, Shields TM, Hackman A, Shiff C, Coetzee M, Koekemoer LL, Munyati S, Gwanzura L, Mutambu S, Stevenson JC, Thuma PE, Norris DE, Bailey JA, Juliano JJ, Chongwe G, Mulenga M, Simulundu E, Mharakurwa S, Agre P, Moss WJ. Policy Implications of the Southern and Central Africa International Center of Excellence for Malaria Research: Ten Years of Malaria Control Impact Assessments in Hypo-, Meso-, and Holoendemic Transmission Zones in Zambia and Zimbabwe. Am J Trop Med Hyg 2022; 107:68-74. [PMID: 36228913 PMCID: PMC9662215 DOI: 10.4269/ajtmh.21-1288] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 05/28/2022] [Indexed: 11/07/2022] Open
Abstract
The International Centers of Excellence for Malaria Research (ICEMR) were established by the National Institute of Allergy and Infectious Diseases more than a decade ago to provide multidisciplinary research support to malaria control programs worldwide, operating in endemic areas and contributing technology, expertise, and ultimately policy guidance for malaria control and elimination. The Southern and Central Africa ICEMR has conducted research across three main sites in Zambia and Zimbabwe that differ in ecology, entomology, transmission intensity, and control strategies. Scientific findings led to new policies and action by the national malaria control programs and their partners in the selection of methods, materials, timing, and locations of case management and vector control. Malaria risk maps and predictive models of case detection furnished by the ICEMR informed malaria elimination programming in southern Zambia, and time series analyses of entomological and parasitological data motivated several major changes to indoor residual spray campaigns in northern Zambia. Along the Zimbabwe-Mozambique border, temporal and geospatial data are currently informing investigations into a recent resurgence of malaria. Other ICEMR findings pertaining to parasite and mosquito genetics, human behavior, and clinical epidemiology have similarly yielded immediate and long-term policy implications at each of the sites, often with generalizable conclusions. The ICEMR programs thereby provide rigorous scientific investigations and analyses to national control and elimination programs, without which the impediments to malaria control and their potential solutions would remain understudied.
Collapse
Affiliation(s)
- Amy Wesolowski
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Matthew M. Ippolito
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
- Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mary E. Gebhardt
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Ellen Ferriss
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Jessica L. Schue
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Tamaki Kobayashi
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | | | | | | | | | | | | | | | | | | | | | | | - Andre Hackman
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Clive Shiff
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Maureen Coetzee
- Wits Research Institute for Malaria, Faculty of Health Sciences, University of the Witwatersrand and National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Lizette L. Koekemoer
- Wits Research Institute for Malaria, Faculty of Health Sciences, University of the Witwatersrand and National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Shungu Munyati
- Biomedical Research and Training Institute, Harare, Zimbabwe
| | - Lovemore Gwanzura
- Biomedical Research and Training Institute, Harare, Zimbabwe
- University of Zimbabwe Faculty of Medicine and Health Sciences, Harare, Zimbabwe
| | | | - Jennifer C. Stevenson
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
- Macha Research Trust, Choma, Zambia
| | - Philip E. Thuma
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
- Macha Research Trust, Choma, Zambia
| | - Douglas E. Norris
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | | | - Jonathan J. Juliano
- University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | | | - Modest Mulenga
- Directorate of Research and Postgraduate Studies, Lusaka Apex Medical University, Lusaka, Zambia
| | | | - Sungano Mharakurwa
- Biomedical Research and Training Institute, Harare, Zimbabwe
- Africa University, Mutare, Zimbabwe
| | - Peter Agre
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - William J. Moss
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| |
Collapse
|
34
|
Abstract
BACKGROUND Malaria remains an important public health problem. Research in 1900 suggested house modifications may reduce malaria transmission. A previous version of this review concluded that house screening may be effective in reducing malaria. This update includes data from five new studies. OBJECTIVES To assess the effects of house modifications that aim to reduce exposure to mosquitoes on malaria disease and transmission. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register; Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE (PubMed); Embase (OVID); Centre for Agriculture and Bioscience International (CAB) Abstracts (Web of Science); and the Latin American and Caribbean Health Science Information database (LILACS) up to 25 May 2022. We also searched the World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, and the ISRCTN registry to identify ongoing trials up to 25 May 2022. SELECTION CRITERIA Randomized controlled trials, including cluster-randomized controlled trials (cRCTs), cross-over studies, and stepped-wedge designs were eligible, as were quasi-experimental trials, including controlled before-and-after studies, controlled interrupted time series, and non-randomized cross-over studies. We sought studies investigating primary construction and house modifications to existing homes reporting epidemiological outcomes (malaria case incidence, malaria infection incidence or parasite prevalence). We extracted any entomological outcomes that were also reported in these studies. DATA COLLECTION AND ANALYSIS Two review authors independently selected eligible studies, extracted data, and assessed the risk of bias. We used risk ratios (RR) to compare the effect of the intervention with the control for dichotomous data. For continuous data, we presented the mean difference; and for count and rate data, we used rate ratios. We presented all results with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach. MAIN RESULTS One RCT and six cRCTs met our inclusion criteria, with an additional six ongoing RCTs. We did not identify any eligible non-randomized studies. All included trials were conducted in sub-Saharan Africa since 2009; two randomized by household and four at the block or village level. All trials assessed screening of windows, doors, eaves, ceilings, or any combination of these; this was either alone, or in combination with roof modification or eave tube installation (an insecticidal "lure and kill" device that reduces mosquito entry whilst maintaining some airflow). In one trial, the screening material was treated with 2% permethrin insecticide. In five trials, the researchers implemented the interventions. A community-based approach was adopted in the other trial. Overall, the implementation of house modifications probably reduced malaria parasite prevalence (RR 0.68, 95% CI 0.57 to 0.82; 5 trials, 5183 participants; moderate-certainty evidence), although an inconsistent effect was observed in a subpopulation of children in one study. House modifications reduced moderate to severe anaemia prevalence (RR 0.70, 95% CI 0.55 to 0.89; 3 trials, 3643 participants; high-certainty evidence). There was no consistent effect on clinical malaria incidence, with rate ratios ranging from 0.38 to 1.62 (3 trials, 3365 participants, 4126.6 person-years). House modifications may reduce indoor mosquito density (rate ratio 0.63, 95% CI 0.30 to 1.30; 4 trials, 9894 household-nights; low-certainty evidence), although two studies showed little effect on this parameter. AUTHORS' CONCLUSIONS House modifications - largely screening, sometimes combined with insecticide and lure and kill devices - were associated with a reduction in malaria parasite prevalence and a reduction in people with anaemia. Findings on malaria incidence were mixed. Modifications were also associated with lower indoor adult mosquito density, but this effect was not present in some studies.
Collapse
Affiliation(s)
- Tilly Fox
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | | | - Marty Chaplin
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Mark Napier
- Council for Scientific and Industrial Research, Pretoria, South Africa
- Centre for Development Support, University of the Free State, Bloemfontein, South Africa
| | - Evelyn A Olanga
- Malaria Alert Centre of the College of Medicine, Blantyre, Malawi
| |
Collapse
|
35
|
Goshu EM, Zerefa MD, Tola HH. Occurrence of asymptomatic malaria infection and living conditions in the lowlands of Ethiopia: a community-based cross-sectional study. Infect Dis Poverty 2022; 11:94. [PMID: 36064653 PMCID: PMC9444277 DOI: 10.1186/s40249-022-01018-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/19/2022] [Indexed: 11/16/2022] Open
Abstract
Background A significant decline in malaria burden was documented in previously high burden African countries. Even though the global decline in malaria burden is significant, about 95% of it was typically found in 29 African countries and the decline was affected by COVID-19 in 2020. The considerable reduction in malaria incidence was noted due to effective prevention and treatment efforts, and rapid changes in living conditions. The relationship between the occurrence of asymptomatic malaria infection and household living conditions is well unstudied. This study aimed to determine the association between household living conditions and the occurrence of asymptomatic malaria in the lowlands of Ethiopia. Methods A community-based cross-sectional study was conducted from January to March 2021 in twelve villages of Gambella, Southern Nation Nationalities and People Region and Afar in Ethiopia. A total of 1366 households were randomly selected, interviewed, and tested for malaria by rapid diagnostic test and blood film microscopic examination. Multiple logistic regression model was used to determine the independent association between living conditions and asymptomatic malaria infection. Results The prevalence of asymptomatic malaria infection among individuals living in dwellings built with traditional floor/wall/roof ranges from 8.1% to 8.4% while it ranges from 2.0% to 4.6% among those living in modern floor/wall/roof houses. Dwellings built with traditional wall materials (P = 0.050), spending nights with cattle in the same house (P < 0.001), and availability of kitchen in the main house with no partition (P = 0.004) were significantly associated with asymptomatic malaria infection. Conclusions Asymptomatic malaria infection was 4.3 times higher among occupants residing in dwellings built with traditional wall materials; 5.6 times higher among households spending nights with cattle in the same house, and 2.3 times higher among households with kitchen in the main house with no partition. Therefore, policies and strategies on malaria elimination need to address or target improvements of the above listed living conditions for the community. A multi sectoral action is required to use these social determinants as a vector control strategic addition; and malaria elimination programs are expected to coordinate the implementation. Supplementary Information The online version contains supplementary material available at 10.1186/s40249-022-01018-3.
Collapse
Affiliation(s)
- Endale Mengesha Goshu
- Water and Public Health Stream, Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Meseret Dessalegne Zerefa
- Water and Public Health Stream, Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia
| | - Habteyes Hailu Tola
- Tuberculosis/HIV Research Directorate, Ethiopian Public Health Institute, P.O. Box 1242, Addis Ababa, Ethiopia
| |
Collapse
|
36
|
Narrative Review of the Control and Prevention of Knowlesi Malaria. Trop Med Infect Dis 2022; 7:tropicalmed7080178. [PMID: 36006270 PMCID: PMC9414718 DOI: 10.3390/tropicalmed7080178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 07/28/2022] [Accepted: 08/01/2022] [Indexed: 11/17/2022] Open
Abstract
Despite the reduction in the number of cases of human malaria throughout the world, the incidence rate of knowlesi malaria is continuing to rise, especially in Southeast Asia. The conventional strategies for the prevention and control of human malaria can provide some protection against knowlesi malaria. Despite the numerous studies on the risk factors and the innovative methods that may be used to prevent and control the vectors of Plasmodium knowlesi, the incidence rate remains high. An integrated approach that includes environmental intervention should be adopted in order to ensure the successful control of zoonotic malaria. A combination of personal-level protection, vector control and environmental control may mitigate the risk of Plasmodium knowlesi transmission from macaques to humans and, ultimately, reduce the incidence rate of knowlesi malaria.
Collapse
|
37
|
Chastonay AHM, Chastonay OJ. Housing Risk Factors of Four Tropical Neglected Diseases: A Brief Review of the Recent Literature. Trop Med Infect Dis 2022; 7:tropicalmed7070143. [PMID: 35878154 PMCID: PMC9319438 DOI: 10.3390/tropicalmed7070143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/12/2022] [Accepted: 07/19/2022] [Indexed: 01/27/2023] Open
Abstract
Alongside peace, education, food, income, a stable ecosystem, sustainable resources and social justice, shelter is a prerequisite for health. According to international human rights law, everyone is entitled to an adequate standard of living, which includes adequate housing. Adequate housing, including access to water and sanitation, plays a critical role in the prevention and management of neglected tropical diseases, which affect over 1 billion people worldwide. Inadequate housing conditions represent a risk factor for many of them, e.g., Chagas disease that affects 6–8 million people worldwide, visceral leishmaniasis that kills 20,000–30,000 people/year, lymphatic filariasis which threatens 859 million people worldwide or dengue that has increased 8–10 fold over the last two decades. Vector control strategies for the above-mentioned diseases have shown their effectiveness and should include systematic and repetitive in-house spraying and individual protection (e.g., impregnated nets), as well as better-quality construction material and techniques and better sanitation infrastructures and practices. Access to adequate housing is a basic human right. The violation of the right to adequate housing may affect the enjoyment of other human rights. Access to adequate housing can strengthen (and facilitate access to) other basic human rights, such as the rights to work, health, security, and education.
Collapse
Affiliation(s)
| | - Oriane J. Chastonay
- Réseau Fribourgeois de Santé Mentale, 1700 Fribourg, Switzerland
- Correspondence:
| |
Collapse
|
38
|
Tizifa TA, Gowelo S, Kabaghe AN, McCann RS, Malenga T, Nkhata RM, Kadama A, Chapeta Y, Takken W, Phiri KS, van Vugt M, van den Berg H, Manda-Taylor L. Community-based house improvement for malaria control in southern Malawi: Stakeholder perceptions, experiences, and acceptability. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000627. [PMID: 36962454 PMCID: PMC10021647 DOI: 10.1371/journal.pgph.0000627] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 05/23/2022] [Indexed: 11/18/2022]
Abstract
House improvement (HI) refers to the full screening or closing of openings such as windows, doors, and eaves, as well as the installation of ceilings, to reduce mosquito-human contact indoors. HI is a viable supplementary intervention that reduces malaria transmission further than the existing strategies alone. In Malawi, HI has not been widely implemented and evaluated for malaria control. Concerns about lack of local evidence, durability in different epidemiological and cultural settings, and the cost of large-scale implementation are among the reasons the strategy is not utilised in many low-income countries. This study assessed community perceptions, experiences, and acceptability of community-led HI in Chikwawa district, southern Malawi. This was a qualitative study where separate focus group discussions were conducted with members from the general community (n = 3); health animators (n = 3); and HI committee members (n = 3). In-depth interviews were conducted with community members (n = 20), and key-informant interviews were conducted with health surveillance assistants and chiefs (n = 23). All interviews were transcribed and coded before performing a thematic content analysis to identify the main themes. Coded data were analysed using Nvivo 12 Plus software. Study participants had a thorough understanding of HI. Participants expressed satisfaction with HI, and they reported enabling factors to HI acceptability, such as the reduction in malaria cases in their villages and the safety and effectiveness of HI use. Participants also reported barriers to effective HI implementation, such as the unavailability and inaccessibility of some HI materials, as well as excessive heat and darkness in HI houses compared to non-HI houses. Participants indicated that they were willing to sustain the intervention but expressed the need for strategies to address barriers to ensure the effectiveness of HI. Our results showed the high knowledge and acceptability of HI by participants in the study area. Intensive and continued health education and community engagement on the significance of HI could help overcome the barriers and improve the acceptability and sustainability of the intervention.
Collapse
Affiliation(s)
- Tinashe A. Tizifa
- Division of Internal Medicine, Department of Infectious Diseases, Center for Tropical Medicine and Travel Medicine, University of Amsterdam, Amsterdam University Medical Center, Location Academic Medical Center, Amsterdam, The Netherlands
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Steven Gowelo
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - Alinune N. Kabaghe
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Robert S. McCann
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
- Centre for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Tumaini Malenga
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
- African Institute for Development Policy, Lilongwe, Malawi
| | - Richard M. Nkhata
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Asante Kadama
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Yankho Chapeta
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
- Biological Sciences Department, Mzuzu University, Mzuzu, Malawi
| | - Willem Takken
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - Kamija S. Phiri
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Michele van Vugt
- Division of Internal Medicine, Department of Infectious Diseases, Center for Tropical Medicine and Travel Medicine, University of Amsterdam, Amsterdam University Medical Center, Location Academic Medical Center, Amsterdam, The Netherlands
| | - Henk van den Berg
- Laboratory of Entomology, Wageningen University & Research, Wageningen, The Netherlands
| | - Lucinda Manda-Taylor
- School of Public Health and Family Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| |
Collapse
|
39
|
Okumu F, Gyapong M, Casamitjana N, Castro MC, Itoe MA, Okonofua F, Tanner M. What Africa can do to accelerate and sustain progress against malaria. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000262. [PMID: 36962314 PMCID: PMC10021840 DOI: 10.1371/journal.pgph.0000262] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
After a longstanding global presence, malaria is now largely non-existent or suppressed in most parts of the world. Today, cases and deaths are primarily concentrated in sub-Saharan Africa. According to many experts, this persistence on the African continent reflects factors such as resistance to insecticides and drugs as well as insufficient access to essential commodities such as insecticide-treated nets and effective drugs. Crucially, however, this narrative ignores many central weaknesses in the fight against malaria and instead reinforces a narrow, commodity-driven vision of disease control. This paper therefore describes the core challenges hindering malaria programs in Africa and highlights key opportunities to rethink current strategies for sustainable control and elimination. The epidemiology of malaria in Africa presents far greater challenges than elsewhere and requires context-specific initiatives tailored to national and sub-national targets. To sustain progress, African countries must systematically address key weaknesses in its health systems, improve the quality and use of data for surveillance-responses, improve both technical and leadership competencies for malaria control, and gradually reduce overreliance on commodities while expanding multisectoral initiatives such as improved housing and environmental sanitation. They must also leverage increased funding from both domestic and international sources, and support pivotal research and development efforts locally. Effective vaccines and drugs, or other potentially transformative technologies such as genedrive modified mosquitoes, could further accelerate malaria control by complementing current tools. However, our underlying strategies remain insufficient and must be expanded to include more holistic and context-specific approaches critical to achieve and sustain effective malaria control.
Collapse
Affiliation(s)
| | - Margaret Gyapong
- Centre for Health Policy and Implementation Research, Institute of Health Research, University of Health and Allied Sciences, Ho, Ghana
| | - Núria Casamitjana
- Barcelona Institute for Global Health (ISGlobal), Hospital Clinic–University of Barcelona, Barcelona, Spain
| | - Marcia C. Castro
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Maurice A. Itoe
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Friday Okonofua
- Department of Obstetrics and Gynaecology, School of Medicine, University of Benin, Benin City, Nigeria
| | - Marcel Tanner
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| |
Collapse
|
40
|
Mshamu S, Mmbando A, Meta J, Bradley J, Bøjstrup TC, Day NPJ, Mukaka M, Okumu F, Olotu A, Pell C, Deen J, Knudsen J, Lindsay SW, von Seidlein L. Assessing the impact of a novel house design on the incidence of malaria in children in rural Africa: study protocol for a household-cluster randomized controlled superiority trial. Trials 2022; 23:519. [PMID: 35725486 PMCID: PMC9207857 DOI: 10.1186/s13063-022-06461-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 06/09/2022] [Indexed: 11/10/2022] Open
Abstract
Background Traditional rural housing in hot, humid regions of sub-Saharan Africa usually consists of single-level, poorly ventilated dwellings. Houses are mostly poorly screened against malaria mosquitoes and limited airflow discourages the use of bednets resulting in high indoor transmission. This study aims to determine whether living in a novel design house with elevated bedrooms and permeable screened walls reduces malaria, respiratory tract infections, and diarrhoea among children in rural Tanzania. Methods/study design This is a household-randomized, controlled study in 60 villages in Mtwara, Tanzania. A total of 550 households are randomly selected, 110 of which are allocated a novel design house and 440 households continue to reside in traditional houses. A dynamic cohort of about 1650 children under 13 years will be enrolled and followed for 3 years, approximately 330 living in novel design houses and 1320 in traditional rural houses. The primary endpoint is the incidence of malaria; secondary endpoints are incidences of acute respiratory tract infections and diarrhoea diseases detected by passive and active surveillance. Exposure to malaria vectors will be assessed using light traps in all study houses. Structural, economic, and social science studies will assess the durability, cost-effectiveness, and acceptability of the new houses compared with traditional housing. Environmental data will be collected indoors and outdoors in study homes to assess the differences between house typologies. Discussion This is the first randomized controlled trial to assess the protective efficacy of a new house design targeting malaria in sub-Saharan Africa. The findings of this study could influence the future construction of homes in hot and humid zones of Africa. Trial registration ClinicalTrials.govNCT04529434. Registered on August 27, 2020
Collapse
Affiliation(s)
- Salum Mshamu
- CSK Research Solutions, Mtwara, Tanzania.,Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Arnold Mmbando
- Ifakara Health Institute, Ifakara, Tanzania.,Department of Biosciences, Durham University, Durham, UK
| | - Judith Meta
- University of Amsterdam, Amsterdam, Netherlands
| | - John Bradley
- MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | | | - Nicholas P J Day
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Mavuto Mukaka
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | | | - Ally Olotu
- Ifakara Health Institute, Ifakara, Tanzania
| | | | | | - Jakob Knudsen
- The Royal Danish Academy of Fine Arts, Copenhagen, Denmark
| | | | - Lorenz von Seidlein
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK. .,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand.
| |
Collapse
|
41
|
Asale A, Kassie M, Abro Z, Enchalew B, Belay A, Sangoro PO, Tchouassi DP, Mutero CM. The combined impact of LLINs, house screening, and pull-push technology for improved malaria control and livelihoods in rural Ethiopia: study protocol for household randomised controlled trial. BMC Public Health 2022; 22:930. [PMID: 35538444 PMCID: PMC9088127 DOI: 10.1186/s12889-022-12919-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 03/04/2022] [Indexed: 11/23/2022] Open
Abstract
Background The combined application of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are commonly used malaria interventions that target indoor Anopheles vectors. Recent studies on the effects of house screening (HS) and LLINs have demonstrated a reduction in indoor vector densities and malaria when the interventions are combined. In addition, complementary interventions are needed to curb co-occurring pest populations which pose menace to agricultural crop productivity and food security. However, interventions that impact malaria mainly centre on public health strategies, overlooking subtle but important component of agricultural measures. Addressing the coexisting risks of malaria and crop pests could contribute to improved livelihood of communities. Methods A four-armed household, cluster-randomized, controlled study will be conducted to assess the combined impact of HS, LLINs and push-pull agricultural technology (PPT) against clinical malaria in children in Ethiopia. The unit of randomization will be the household, which includes a house and its occupants. A total of 838 households will be enrolled in this study. In this trial 246 households will receive LLINs and HS, 250 will receive LLINs, HS and PPT, 175 households will receive LLINs and PPT. The remaining 167 houses which receive LLINs only will be used as control. One child aged ≤14 years will be enrolled per household in each treatment and followed for clinical malaria using active case detection to estimate malaria incidence for two malaria transmission seasons. Discussion Episodes of clinical malaria, density of indoor biting malaria vectors, sporozoite infection rate, improved crop infestation rate, crop yield gain, livestock productivity and cost effectiveness analysis will be the end points of this study. Socio-economic, social demographic, cost-effectiveness analysis will be conducted using qualitative and participatory methods to explore the acceptability of HS and PPT. Documenting the combined impact of LLINs, HS and PPT on the prevalence of clinical malaria and crop pest damage will be the first of its kind. Trial registration Pan African Clinical Trials Registry, PACTR202006878245287. 24/06/2020. https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=11101. Supplementary Information The online version contains supplementary material available at 10.1186/s12889-022-12919-1.
Collapse
Affiliation(s)
- Abebe Asale
- International Centre of Insect Physiology and Ecology, Addis Ababa, Ethiopia.
| | - Menale Kassie
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Zewdu Abro
- International Centre of Insect Physiology and Ecology, Addis Ababa, Ethiopia
| | - Bayu Enchalew
- International Centre of Insect Physiology and Ecology, Addis Ababa, Ethiopia
| | - Aklilu Belay
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya.,University of Pretoria Institute for Sustainable Malaria Control, School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa
| | - Peter O Sangoro
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - David P Tchouassi
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Clifford M Mutero
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya.,University of Pretoria Institute for Sustainable Malaria Control, School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
42
|
Dirontsho M, Ntombi NB, Dare KO, Ronald MM, Vincent P. LOCAL KNOWLEDGE OF ADAPTIVE STRATEGIES AGAINST MALARIA ENDEMICITY IN THE OKAVANGO DELTA, BOTSWANA. Afr J Infect Dis 2022; 16:21-34. [PMID: 35582062 PMCID: PMC9097314 DOI: 10.21010/ajid.v16i2.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 08/22/2021] [Accepted: 08/31/2021] [Indexed: 11/23/2022] Open
Abstract
Background An increasing recognition of the need to eliminate malaria infection globally and particularly in Africa where more than 90% of the cases originate, should enhance community awareness and participation in the same. The perennial freshwater of Okavango Delta located in northern Botswana, which is a source of rural livelihoods and a suitable habitat for the malaria-causing mosquito, and where malaria is endemic provides a suitable environment for the study. Therefore, local households' adaptive strategies against malaria transmission in the Okavango Delta were investigated. Materials and Methods The data used in this paper is a subset or retrospective cohort of 79 households that reported malaria cases/incidences during the first community level household survey conducted from October-November 2015 on 355 households in Shakawe and Ngarange. The households were selected through stratified random sampling in the two study villages. The retrospective cohort household survey was conducted from 7-19 August 2016, in the two study sites. Data were collected through socio-economic survey, key informants' interviews and focus group discussions. Results The results obtained indicate that most cohort households embraced several adaptive strategies against malaria transmission. These included, inter alia, knowledge capacity building through attendance of health information and education workshops (69%), modifications of houses structures (49.4%), timing of activities and restricting movement at certain times of the day (43%). Discussion Although most of the stated adaptive strategies such as house screening were not exclusively aimed towards malaria prevention and adaptation, they nonetheless had postive spill over effect that could be a catalyst for eliminating malaria in the study area.
Collapse
Affiliation(s)
- Maphane Dirontsho
- Office of District Commissioner, Ministry of Local Government, Gaborone, Botswana
| | | | | | | | | |
Collapse
|
43
|
Woolley KE, Bartington SE, Pope FD, Greenfield SM, Tusting LS, Price MJ, Thomas GN. Cooking outdoors or with cleaner fuels does not increase malarial risk in children under 5 years: a cross-sectional study of 17 sub-Saharan African countries. Malar J 2022; 21:133. [PMID: 35477567 PMCID: PMC9044678 DOI: 10.1186/s12936-022-04152-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 04/06/2022] [Indexed: 12/02/2022] Open
Abstract
Background Smoke from solid biomass cooking is often stated to reduce household mosquito levels and, therefore, malarial transmission. However, household air pollution (HAP) from solid biomass cooking is estimated to be responsible for 1.67 times more deaths in children aged under 5 years compared to malaria globally. This cross-sectional study investigates the association between malaria and (i) cleaner fuel usage; (ii) wood compared to charcoal fuel; and, (iii) household cooking location, among children aged under 5 years in sub-Saharan Africa (SSA). Methods Population-based data was obtained from Demographic and Health Surveys (DHS) for 85,263 children within 17 malaria-endemic sub-Saharan countries who were who were tested for malaria with a malarial rapid diagnostic test (RDT) or microscopy. To assess the independent association between malarial diagnosis (positive, negative), fuel type and cooking location (outdoor, indoor, attached to house), multivariable logistic regression was used, controlling for individual, household and contextual confounding factors. Results Household use of solid biomass fuels and kerosene cooking fuels was associated with a 57% increase in the odds ratio of malarial infection after adjusting for confounding factors (RDT adjusted odds ratio (AOR):1.57 [1.30–1.91]; Microscopy AOR: 1.58 [1.23–2.04]) compared to cooking with cleaner fuels. A similar effect was observed when comparing wood to charcoal among solid biomass fuel users (RDT AOR: 1.77 [1.54–2.04]; Microscopy AOR: 1.21 [1.08–1.37]). Cooking in a separate building was associated with a 26% reduction in the odds of malarial infection (RDT AOR: 0.74 [0.66–0.83]; Microscopy AOR: 0.75 [0.67–0.84]) compared to indoor cooking; however no association was observed with outdoor cooking. Similar effects were observed within a sub-analysis of malarial mesoendemic areas only. Conclusion Cleaner fuels and outdoor cooking practices associated with reduced smoke exposure were not observed to have an adverse effect upon malarial infection among children under 5 years in SSA. Further mixed-methods research will be required to further strengthen the evidence base concerning this risk paradigm and to support appropriate public health messaging in this context. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04152-3.
Collapse
Affiliation(s)
- Katherine E Woolley
- Institute of Applied Health Research, University of Birmingham, Edgbaston, Birmingham, UK
| | - Suzanne E Bartington
- Institute of Applied Health Research, University of Birmingham, Edgbaston, Birmingham, UK.
| | - Francis D Pope
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Sheila M Greenfield
- Institute of Applied Health Research, University of Birmingham, Edgbaston, Birmingham, UK
| | - Lucy S Tusting
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK.,Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Malcolm J Price
- Institute of Applied Health Research, University of Birmingham, Edgbaston, Birmingham, UK.,NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust and University of Birmingham, Birmingham, UK
| | - G Neil Thomas
- Institute of Applied Health Research, University of Birmingham, Edgbaston, Birmingham, UK
| |
Collapse
|
44
|
Opiyo M, Sherrard-Smith E, Malheia A, Nhacolo A, Sacoor C, Nhacolo A, Máquina M, Jamu L, Cuamba N, Bassat Q, Saúte F, Paaijmans K. Household modifications after the indoor residual spraying (IRS) campaign in Mozambique reduce the actual spray coverage and efficacy. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000227. [PMID: 36962153 PMCID: PMC10021718 DOI: 10.1371/journal.pgph.0000227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 03/02/2022] [Indexed: 11/18/2022]
Abstract
Indoor residual spraying of insecticides (IRS) is a key malaria vector control strategy. Whilst human attitude towards IRS is monitored before or shortly after implementation, human activities leading to the modification of insecticide-treated walls post-IRS are not. This could inadvertently reduce the protective effects of IRS. We monitored the extent of modifications to the sprayed indoor wall surfaces by household owners for six months post-IRS campaigns in two districts targeted for malaria elimination in southern Mozambique. In parallel, we assessed building of any additional rooms onto compounds, and mosquito net use. We quantified the contribution of wall modifications, added rooms, prolonged spray campaigns, and product residual efficacies on actual IRS coverage and relative mosquito bite reduction, using a mechanistic approach. Household owners continually modified insecticide-treated walls and added rooms onto compounds. Household surveys in southern Mozambique showed frequent modification of indoor walls (0-17.2% of households modified rooms monthly) and/or added rooms (0-16.2% of households added rooms monthly). Actual IRS coverage reduced from an assumed 97% to just 39% in Matutuine, but only from 96% to 91% in Boane, translating to 43% and 5.8% estimated increases in relative daily mosquito bites per person. Integrating post-IRS knowledge, attitude, and practice (KAP) surveys into programmatic evaluations to capture these modification and construction trends can help improve IRS program efficiency and product assessment.
Collapse
Affiliation(s)
- Mercy Opiyo
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Ellie Sherrard-Smith
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, United Kingdom
| | - Arlindo Malheia
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Arsenio Nhacolo
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Charfudin Sacoor
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Ariel Nhacolo
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Mara Máquina
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Luis Jamu
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Nelson Cuamba
- National Malaria Control Programme of Mozambique (NMCP), Ministry of Health, Maputo, Mozambique
- PMI VectorLink Project, Abt Associates Inc., Maputo, Mozambique
| | - Quique Bassat
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- ICREA, Barcelona, Spain
- Pediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Esplugues, Barcelona, Spain
- Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Francisco Saúte
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Krijn Paaijmans
- Barcelona Institute for Global Health (ISGlobal), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
- The Biodesign Center for Immunotherapy, Vaccines, and Virotherapy, Arizona State University, Tempe, Arizona, United States of America
- Simon A. Levin Mathematical, Computational and Modeling Sciences Center, Arizona State University, Tempe, Arizona, United States of America
| |
Collapse
|
45
|
Minakawa N, Kawada H, Kongere JO, Sonye GO, Lutiali PA, Awuor B, Isozumi R, Futami K. Effectiveness of screened ceilings over the current best practice in reducing malaria prevalence in western Kenya: a cluster randomised controlled trial. Parasitology 2022; 149:1-39. [PMID: 35437129 PMCID: PMC10090608 DOI: 10.1017/s0031182022000415] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 03/13/2022] [Accepted: 03/17/2022] [Indexed: 11/06/2022]
Abstract
Increases in bed net coverage and antimalarial treatment have reduced the risk of malaria in sub-Saharan Africa. However, the pace of reduction has slowed, and new tools are needed to reverse this trend. We evaluated houses screened with insecticide-treated ceiling nets using a cluster randomized-controlled trial in western Kenya. The primary endpoints were Plasmodium falciparum PCR-positive prevalence (PCRPf PR) of children from 7 months to 10 years old and anopheline density. Ceiling nets and bed nets were provided to 1073 houses, and 1162 houses were provided with bed nets only. The treatment and control arms each had four clusters. We conducted three epidemiological and entomological post-intervention surveys over the course of a year and a half. Each epidemiological survey targeted 150 children per cluster, and entomological surveys targeted 25 houses. When the three surveys were combined, the median PCRPf PRs were 23% (IQR 8%) in the intervention arm and 42% (IQR 12%) in the control arm. The adjusted risk ratio (RR) was 0.53 [95% confidence interval (CI) 0.41–0.71; P = 0.029]. The median anopheline densities were 0.4 (IQR 0.4) and 2.0 (IQR 1.4), respectively. The adjusted RR was 0.41 (95% CI 0.29–0.90; P = 0.029). The present study indicates additional protection from insecticide-screened ceilings over the current best practice.
Collapse
Affiliation(s)
- Noboru Minakawa
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan
| | - Hitoshi Kawada
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan
| | - James O. Kongere
- Kenya Medical Research Institute, Nairobi, Kenya
- Center for Research in Tropical Medicine and Community Development (CRTMCD), Nairobi, Kenya
| | | | - Peter A. Lutiali
- Kenya Medical Research Institute, Nairobi, Kenya
- Center for Research in Tropical Medicine and Community Development (CRTMCD), Nairobi, Kenya
| | | | - Rie Isozumi
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan
| | - Kyoko Futami
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki 852-8523, Japan
| |
Collapse
|
46
|
Saberi N, Raeisi A, Gorouhi MA, Vatandoost H, Mashayekhi M, Nikpour F, Bozorg Omid F, Rahimi Foroushani A, Hanafi-Bojd AA. Current Situation of Malaria and Resistance of Main Vectors to WHO Recommended Insecticides in an Endemic Area, Southeastern Iran. JOURNAL OF MEDICAL ENTOMOLOGY 2022; 59:607-614. [PMID: 34958095 DOI: 10.1093/jme/tjab214] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Indexed: 06/14/2023]
Abstract
Although malaria is endemic in some areas of southeastern Iran, following the successful national malaria elimination plan, the local transmission area has been shrunk. The main cases in Iran are due to Plasmodium vivax followed by P. falciparum. This study was aimed to determine the current situation of malaria in Kerman Province of Iran and evaluate the insecticide resistance of main vectors. The field study was conducted in 2019. Data of new malaria cases were obtained from the health centers for the period of 2009-2018. Susceptibility status of Anopheles stephensi and An. dthali was evaluated against dichlorodiphenyltrichloroethane, Dieldrin, Malathion, Bendiocarb, Deltamethrin, and Temephos at the diagnostic dose. A total of 522 malaria cases were recorded and divided into indigenous (33.14%) and imported (66.86%) categories. The highest incidence of the disease was reported from the southern areas of the province, where all indigenous cases occurred. Adults of An. stephensi were resistant to dichlorodiphenyltrichloroethane while its resistance to be confirmed to dieldrin, bendiocarb and deltamethrin. As An. dthali had less than 98% mortality against bendiocarb, the resistance status should be confirmed with more tests. Our findings showed both species had less than 98% mortality against bendiocarb and deltamethrin insecticides which are used in malaria vector control program in Iran. Due to the susceptibility of these vectors to temephos, larviciding can be advised for vector control in this area.
Collapse
Affiliation(s)
- Nasrollah Saberi
- Department of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Raeisi
- Department of Medical Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Amin Gorouhi
- Research Center of Tropical and Infectious Diseases, Kerman University of Medical Sciences, Kerman, Iran
- Department of Medical Entomology & Vector Control, School of Public Health, Kerman University of Medical Sciences, Kerman, Iran
| | - Hassan Vatandoost
- Department of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
- Department of Environmental Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Minoo Mashayekhi
- Department of Prevention and Control of diseases, Deputy of Health, Kerman University of Medical Sciences, Kerman, Iran
| | - Fatemeh Nikpour
- Department of Environmental Chemical Pollutants and Pesticides, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran
| | - Faramarz Bozorg Omid
- Department of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Abbas Rahimi Foroushani
- Department of Epidemiology & Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Ali Hanafi-Bojd
- Department of Medical Entomology & Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
- Zoonoses Research Center, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
47
|
Nguyen TT, Nguyen XX, Wilson-Barthes M, Sawada I, Muela J, Hausmann-Muela S, Pham TV, Van Nguyen H, Van Nguyen V, Tran DT, Gryseels C, D'Alessandro U, Grietens KP, Erhart A. Why using bed nets is a challenge among minority populations in Central Vietnam. Malar J 2022; 21:87. [PMID: 35292018 PMCID: PMC8922825 DOI: 10.1186/s12936-022-04114-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 03/02/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Despite freely distributed insecticide-treated nets (ITNs) and health information campaigns to increase their use among populations at risk, malaria transmission persists in forested areas in Vietnam, especially among ethnic minority communities. A mixed-methods study was conducted in four villages of Ca Dong and M'nong ethnicity in Central Vietnam between 2009 and 2011 to assess factors limiting the uptake of ITNs. METHODS The mixed-methods research design consisted of a qualitative study to explore the context and barriers to ITN use, and a cross-sectional household survey (n = 141) to quantify factors for limited and appropriate net use. RESULTS The Ca Dong and M'nong's livelihood was dependent on swidden farming in the forest. Poverty-related factors, including the lack of beds, blankets, the practice of sleeping around the kitchen fire and deteriorated ITNs due to open housing structures, were reasons for alternative and non-use of ITNs. When household members stayed overnight in plot huts at fields, ITNs were even more unavailable and easily deteriorated. 72.5% of households reported having received one net for every two persons, and 82.2% of participants reported to have used ITNs the night before the survey. However, only 18.4% of participants were estimated to be effectively protected by ITNs after accounting for the availability of torn ITNs and the way ITNs were used, for example as blankets, at both village and fields. Multi-variable logistic regression showed the effect of four significant factors for appropriate ITN use: i) being female (AOR = 8.08; p = 0.009); ii) aware of mosquito bites as the sole cause of malaria (AOR = 7.43; p = 0.008); iii) not sleeping around the kitchen fire (AOR = 24.57; p = 0.001); and iv) having sufficient number of ITNs in the household (AOR = 21.69; p = 0.001). CONCLUSION This study showed how social factors rooted in poverty and swidden agriculture limited the effective use of ITNs, despite high coverage, among ethnic minority populations in Central Vietnam. An in-depth understanding of the local context is essential to develop specific indicators for measuring ITN use.
Collapse
Affiliation(s)
- Thuan Thi Nguyen
- Socio-Ecological Health Research Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium. .,National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam.
| | - Xa Xuan Nguyen
- National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Marta Wilson-Barthes
- International Health Institute, Brown University School of Public Health, Providence, USA
| | - Ikumi Sawada
- Department of Clinical Tropical Medicine, Institute of Tropical Medicine, Graduate School of Biomedical Science, Nagasaki University, Nagasaki, Japan
| | - Joan Muela
- University Ramon I Virgili, Tarragona, Spain.,Partners for Applied Social Sciences, PASS International, Tessenderlo, Belgium
| | | | - Thanh Vinh Pham
- National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Hong Van Nguyen
- National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | | | - Duong Thanh Tran
- National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Charlotte Gryseels
- Socio-Ecological Health Research Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Koen Peeters Grietens
- Socio-Ecological Health Research Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.,Partners for Applied Social Sciences, PASS International, Tessenderlo, Belgium.,School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
| | - Annette Erhart
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| |
Collapse
|
48
|
Nieto-Sanchez C, Dens S, Solomon K, Haile A, Yuan Y, Hawer T, Yewhalaw D, Addissie A, Grietens KP. Beyond eves and cracks: An interdisciplinary study of socio-spatial variation in urban malaria transmission in Ethiopia. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000173. [PMID: 36962186 PMCID: PMC10021683 DOI: 10.1371/journal.pgph.0000173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 02/23/2022] [Indexed: 11/18/2022]
Abstract
During the past century, the global trend of reduced malaria transmission has been concurrent with increasing urbanization. Although urbanization has traditionally been considered beneficial for vector control, the adaptation of malaria vectors to urban environments has created concerns among scientific communities and national vector control programs. Since urbanization rates in Ethiopia are among the highest in the world, the Ethiopian government developed an initiative focused on building multi-storied units organized in condominium housing. This study aimed to develop an interdisciplinary methodological approach that integrates architecture, landscape urbanism, medical anthropology, and entomology to characterize exposure to malaria vectors in this form of housing in three condominiums in Jimma Town. Mosquitoes were collected using light trap catches (LTCs) both indoor and outdoor during 2019's rainy season. Architectural drawings and ethnographic research were superposed to entomological data to detect critical interactions between uses of the space and settlement conditions potentially affecting malaria vector abundance and distribution. A total of 34 anopheline mosquitoes comprising three species (Anopheles gambiae s.l, An. pharoensis and An. coustani complex) were collected during the three months of mosquito collection. Anopheles gambiae s.l, the principal malaria vector in Ethiopia, was the predominant species of all the anophelines collected. Distribution of mosquito breeding sites across scales (household, settlement, urban landscape) is explained by environmental conditions, socio-cultural practices involving modification of existing spaces, and systemic misfits between built environment and territory. Variations in mosquito abundance and distribution in this study were mainly related to standard building practices that ignore the original logics of the territory, deficiency of water and waste disposal management systems, and adaptations of the space to fit heterogeneous lifestyles of residents. Our results indicate that contextualizing malaria control strategies in relation to vector ecology, social dynamics determining specific uses of the space, as well as building and territorial conditions could strengthen current elimination efforts. Although individual housing remains a critical unit of research for vector control interventions, this study demonstrates the importance of studying housing settlements at communal level to capture systemic interactions impacting transmission at the household level and in outdoor areas.
Collapse
Affiliation(s)
- Claudia Nieto-Sanchez
- Department of Public Health, Unit of Socio-Ecological Health Research, Institute of Tropical Medicine, Antwerp, Belgium
| | - Stefanie Dens
- Witteveen+Bos Belgium N.V., Antwerp, Belgium
- Research Group for Urban Development, Faculty of Design Sciences, University of Antwerp, Antwerp, Belgium
| | - Kalkidan Solomon
- Department of Preventive Medicine, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Asgedom Haile
- Ethiopian Institute of Architecture, Building Construction, and City Development (EiABC), Addis Ababa University, Addis Ababa, Ethiopia
| | - Yue Yuan
- Faculty of Medicine, University of British Columbia, Vancouver, Canada
| | | | - Delenasaw Yewhalaw
- Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
| | - Adamu Addissie
- Department of Preventive Medicine, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Koen Peeters Grietens
- Department of Public Health, Unit of Socio-Ecological Health Research, Institute of Tropical Medicine, Antwerp, Belgium
- Witteveen+Bos Belgium N.V., Antwerp, Belgium
- Research Group for Urban Development, Faculty of Design Sciences, University of Antwerp, Antwerp, Belgium
- Department of Preventive Medicine, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
- Ethiopian Institute of Architecture, Building Construction, and City Development (EiABC), Addis Ababa University, Addis Ababa, Ethiopia
- Faculty of Medicine, University of British Columbia, Vancouver, Canada
- Department of Medical Laboratory Sciences and Pathology, College of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center, Jimma University, Jimma, Ethiopia
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
| |
Collapse
|
49
|
Sangoro OP, Fillinger U, Saili K, Nkya TE, Marubu R, Masaninga F, Trigo SC, Tarumbwa C, Hamainza B, Baltazar C, Mberikunashe J, Chisanga B, Menale K, Chanda E, Mutero CM. Evaluating the efficacy, impact, and feasibility of community-based house screening as a complementary malaria control intervention in southern Africa: a study protocol for a household randomized trial. Trials 2021; 22:883. [PMID: 34872600 PMCID: PMC8646012 DOI: 10.1186/s13063-021-05768-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 10/27/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Concerted effort to control malaria has had a substantial impact on the transmission of the disease in the past two decades. In areas where reduced malaria transmission is being sustained through insecticide-based vector control interventions, primarily long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), non-insecticidal complementary tools will likely be needed to push towards malaria elimination. Once interruption in local disease transmission is achieved, insecticide-based measures can be scaled down gradually and eventually phased out, saving on costs of sustaining control programs and mitigating any unintended negative health and environmental impacts posed by insecticides. These non-insecticidal methods could eventually replace insecticidal methods of vector control. House screening, a non-insecticidal method, has a long history in malaria control, but is still not widely adopted in sub-Saharan Africa. This study aims to add to the evidence base for this intervention in low transmission settings by assessing the efficacy, impact, and feasibility of house screening in areas where LLINs are conventionally used for malaria control. METHODS A two-armed, household randomized clinical trial will be conducted in Mozambique, Zambia, and Zimbabwe to evaluate whether combined the use of house screens and LLINs affords better protection against clinical malaria in children between 6 months and 13 years compared to the sole use of LLINs. Eight hundred households will be enrolled in each study area, where 400 households will be randomly assigned the intervention, house screening, and LLINs while the control households will be provided with LLINs only. Clinical malaria incidence will be estimated by actively following up one child from each household for 6 months over the malaria transmission season. Cross-sectional parasite prevalence will be estimated by testing all participating children for malaria parasites at the beginning and end of each transmission season using rapid diagnostic tests. CDC light traps and pyrethrum spray catches (PSC) will be used to sample adult mosquitoes and evaluate the impact of house screening on indoor mosquito density, species distribution, and sporozoite rates. DISCUSSION This study will contribute epidemiological data on the impact of house screening on malaria transmission and assess the feasibility of its implementation on a programmatic scale. TRIAL REGISTRATION ClinicalTrials.gov PACTR202008524310568 . Registered on August 11, 2020.
Collapse
Affiliation(s)
- Onyango P Sangoro
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya.
| | - Ulrike Fillinger
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Kochelani Saili
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- School of Health Systems & Public Health, University of Pretoria, Pretoria, South Africa
| | | | - Rose Marubu
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | | | | | | | | | | | | | - Brian Chisanga
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- Department of Social Sciences, Wageningen University and Research, Wageningen, Netherlands
| | - Kassie Menale
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
| | - Emmanuel Chanda
- World Health Organization, Regional Office for Africa, Brazzaville, Congo
| | - Clifford Maina Mutero
- International Centre of Insect Physiology and Ecology, Nairobi, Kenya
- School of Health Systems & Public Health, University of Pretoria, Pretoria, South Africa
| |
Collapse
|
50
|
The Effect of Socioeconomic Factors and Indoor Residual Spraying on Malaria in Mangaluru, India: A Case-Control Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182211853. [PMID: 34831610 PMCID: PMC8618973 DOI: 10.3390/ijerph182211853] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/05/2021] [Accepted: 11/10/2021] [Indexed: 11/17/2022]
Abstract
India faces 0.5 million malaria cases annually, including half of all Plasmodium vivax malaria cases worldwide. This case–control study assessed socioeconomic determinants of urban malaria in coastal Mangaluru, Karnataka, southwestern India. Between June and December 2015, we recruited 859 malaria patients presenting at the governmental Wenlock Hospital and 2190 asymptomatic community controls. We assessed clinical, parasitological, and socioeconomic data. Among patients, p. vivax mono-infection (70.1%) predominated. Most patients were male (93%), adult (median, 27 years), had no or low-level education (70.3%), and 57.1% were daily labourers or construction workers. In controls (59.3% male; median age, 32 years; no/low-level education, 54.5%; daily labourers/construction workers, 41.3%), 4.1% showed asymptomatic Plasmodium infection. The odds of malaria was reduced among those who had completed 10th school grade (aOR, 0.3; 95% CI, 0.26–0.42), lived in a building with a tiled roof (aOR, 0.71; 95% CI, 0.53–0.95), and reported recent indoor residual spraying (aOR, 0.02; 95% CI, 0.01–0.04). In contrast, migrant status was a risk factor for malaria (aOR, 2.43; 95% CI, 1.60–3.67). Malaria in Mangaluru is influenced by education, housing condition, and migration. Indoor residual spraying greatly contributes to reducing malaria in this community and should be promoted, especially among its marginalised members.
Collapse
|