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Saili K, de Jager C, Masaninga F, Chisanga B, Sinyolo A, Chiwaula J, Chirwa J, Hamainza B, Chanda E, Bakyaita NN, Mutero CM. Community perceptions, acceptability, and the durability of house screening interventions against exposure to malaria vectors in Nyimba district, Zambia. BMC Public Health 2024; 24:285. [PMID: 38267927 PMCID: PMC10809574 DOI: 10.1186/s12889-024-17750-4] [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: 07/22/2023] [Accepted: 01/11/2024] [Indexed: 01/26/2024] Open
Abstract
BACKGROUND House screening remains conspicuously absent in national malaria programs despite its recognition by the World Health Organization as a supplementary malaria vector-control intervention. This may be attributed, in part, to the knowledge gap in screen durability or longevity in local climatic conditions and community acceptance under specific cultural practices and socio-economic contexts. The objectives of this study were to assess the durability of window and door wire mesh screens a year after full house screening and to assess the acceptability of the house screening intervention to the participants involved. METHODS This study was conducted in Nyimba district, Zambia and used both quantitative and qualitative methods of data collection and analysis. Both direct observation and questionnaires were employed to assess the durability of the screens and the main reasons for damage. Findings on damage were summarized as percentages. Focus group discussions were used to assess people's knowledge, perceptions, and acceptability of the closing eaves and house screening intervention. Deductive coding and inductive coding were used to analyse the qualitative data. RESULTS A total of 321 out of 400 (80.3%) household owners of screened houses were interviewed. Many window screens (90.3%) were intact. In sharp contrast, most door screens were torn (n = 150; 46.7%) or entirely removed (n = 55; 17.1%). Most doors (n = 114; 76%) had their wire mesh damaged or removed on the bottom half. Goats (25.4%), rust (17.6%) and children (17.1%) were cited most as the cause of damage to door screens. The focus group discussion elicited positive experiences from the participants following the closing of eaves and screening of their windows and doors, ranging from sleeping peacefully due to reduced mosquito biting and/or nuisance and having fewer insects in the house. Participants linked house screening to reduced malaria in their households and community. CONCLUSION This study demonstrated that in rural south-east Zambia, closing eaves and screening windows and doors was widely accepted. Participants perceived that house screening reduced human-vector contact, reduced the malaria burden and nuisance biting from other potentially disease carrying insects. However, screened doors are prone to damage, mainly by children, domestic animals, rust, and termites.
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Affiliation(s)
- Kochelani Saili
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. Box 30772-00100, Kenya.
- School of Health Systems & Public Health, University of Pretoria Institute for Sustainable Malaria Control, University of Pretoria, Pretoria, South Africa.
| | - Christiaan de Jager
- School of Health Systems & Public Health, University of Pretoria Institute for Sustainable Malaria Control, University of Pretoria, Pretoria, South Africa
| | | | - Brian Chisanga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. Box 30772-00100, Kenya
- Development Economics Group, Wageningen University and Research, Wageningen, Netherlands
| | - Andy Sinyolo
- National Malaria Elimination Centre, Lusaka, Zambia
| | | | - Jacob Chirwa
- National Malaria Elimination Centre, Lusaka, Zambia
| | | | - Emmanuel Chanda
- World Health Organization, Regional Office, Brazzaville, Congo
| | | | - Clifford Maina Mutero
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, P.O. Box 30772-00100, Kenya
- School of Health Systems & Public Health, University of Pretoria Institute for Sustainable Malaria Control, University of Pretoria, Pretoria, South Africa
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Saili K, de Jager C, Masaninga F, Sangoro OP, Nkya TE, Likulunga LE, Chirwa J, Hamainza B, Chanda E, Fillinger U, Mutero CM. House Screening Reduces Exposure to Indoor Host-Seeking and Biting Malaria Vectors: Evidence from Rural South-East Zambia. Trop Med Infect Dis 2024; 9:20. [PMID: 38251217 PMCID: PMC10821011 DOI: 10.3390/tropicalmed9010020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/31/2023] [Accepted: 01/09/2024] [Indexed: 01/23/2024] Open
Abstract
This study evaluated the impact of combining house screens with long-lasting insecticidal nets (LLINs) on mosquito host-seeking, resting, and biting behavior. Intervention houses received house screens and LLINs, while control houses received only LLINs. Centre for Disease Control light traps, pyrethrum spray collections and human landing catches were used to assess the densities of indoor and outdoor host-seeking, indoor resting, and biting behavior of malaria vectors in 15 sentinel houses per study arm per sampling method. The protective efficacy of screens and LLINs was estimated through entomological inoculation rates (EIRs). There were 68% fewer indoor host-seeking Anopheles funestus (RR = 0.32, 95% CI 0.20-0.51, p < 0.05) and 63% fewer An. arabiensis (RR = 0.37, 95% CI 0.22-0.61, p < 0.05) in screened houses than unscreened houses. There was a significantly higher indoor biting rate for unscreened houses (6.75 bites/person/h [b/p/h]) than for screened houses (0 b/p/h) (χ2 = 6.67, df = 1, p < 0.05). The estimated indoor EIR in unscreened houses was 2.91 infectious bites/person/six months, higher than that in screened houses (1.88 infectious bites/person/six months). Closing eaves and screening doors and windows has the potential to reduce indoor densities of malaria vectors and malaria transmission.
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Affiliation(s)
- Kochelani Saili
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (O.P.S.); (T.E.N.); (U.F.); (C.M.M.)
- University of Pretoria Institute for Sustainable Malaria Control, School of Health Systems & Public Health, University of Pretoria, Pretoria 0028, South Africa;
| | - Christiaan de Jager
- University of Pretoria Institute for Sustainable Malaria Control, School of Health Systems & Public Health, University of Pretoria, Pretoria 0028, South Africa;
| | - Freddie Masaninga
- Country Office, World Health Organization, P.O. Box 32346, Lusaka 10101, Zambia;
| | - Onyango P. Sangoro
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (O.P.S.); (T.E.N.); (U.F.); (C.M.M.)
| | - Theresia E. Nkya
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (O.P.S.); (T.E.N.); (U.F.); (C.M.M.)
- Mbeya College of Health and Allied Sciences, University of Dar es Salaam, Mbeya 35063, Tanzania
| | - Likulunga Emmanuel Likulunga
- Department of Biological Sciences, University of Zambia, Great East Road Campus, P.O. Box 32379, Lusaka 10101, Zambia;
| | - Jacob Chirwa
- National Malaria Elimination Centre, P.O. Box 32509, Lusaka 10101, Zambia; (J.C.); (B.H.)
| | - Busiku Hamainza
- National Malaria Elimination Centre, P.O. Box 32509, Lusaka 10101, Zambia; (J.C.); (B.H.)
| | - Emmanuel Chanda
- WHO Regional Office for Africa, Cite du Djoue, Brazzaville P.O. Box 06, Congo
| | - Ulrike Fillinger
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (O.P.S.); (T.E.N.); (U.F.); (C.M.M.)
| | - Clifford Maina Mutero
- International Centre of Insect Physiology and Ecology (icipe), Nairobi P.O. Box 30772-00100, Kenya; (O.P.S.); (T.E.N.); (U.F.); (C.M.M.)
- University of Pretoria Institute for Sustainable Malaria Control, School of Health Systems & Public Health, University of Pretoria, Pretoria 0028, South Africa;
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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.
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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.
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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.
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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
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Xu M, Hu YX, Lu SN, Idris MA, Zhou SD, Yang J, Feng XN, Huang YM, Xu X, Chen Y, Wang DQ. Seasonal malaria chemoprevention in Africa and China's upgraded role as a contributor: a scoping review. Infect Dis Poverty 2023; 12:63. [PMID: 37403183 DOI: 10.1186/s40249-023-01115-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 06/14/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Children under five are the vulnerable population most at risk of being infected with Plasmodium parasites, especially in the Sahel region. Seasonal malaria chemoprevention (SMC) recommended by World Health Organization (WHO), has proven to be a highly effective intervention to prevent malaria. Given more deaths reported during the COVID-19 pandemic than in previous years due to the disruptions to essential medical services, it is, therefore, necessary to seek a more coordinated and integrated approach to increasing the pace, coverage and resilience of SMC. Towards this end, fully leverage the resources of major players in the global fight against malaria, such as China could accelerate the SMC process in Africa. METHODS We searched PubMed, MEDLINE, Web of Science, and Embase for research articles and the Institutional Repository for Information Sharing of WHO for reports on SMC. We used gap analysis to investigate the challenges and gaps of SMC since COVID-19. Through the above methods to explore China's prospective contribution to SMC. RESULTS A total of 68 research articles and reports were found. Through gap analysis, we found that despite the delays in the SMC campaign, 11.8 million children received SMC in 2020. However, there remained some challenges: (1) a shortage of fully covered monthly courses; (2) lack of adherence to the second and third doses of amodiaquine; (3) four courses of SMC are not sufficient to cover the entire malaria transmission season in areas where the peak transmission lasts longer; (4) additional interventions are needed to consolidate SMC efforts. China was certified malaria-free by WHO in 2021, and its experience and expertise in malaria elimination can be shared with high-burden countries. With the potential to join the multilateral cooperation in SMC, including the supply of quality-assured health commodities, know-how transfer and experience sharing, China is expected to contribute to the ongoing scale-up of SMC. CONCLUSIONS A combination of necessary preventive and curative activities may prove beneficial both for targeted populations and for health system strengthening in the long run. More actions are entailed to promote the partnership and China can be one of the main contributors with various roles.
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Affiliation(s)
- Ming Xu
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Yun-Xuan Hu
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Shen-Ning Lu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Shanghai, China
| | | | - Shu-Duo Zhou
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Jian Yang
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Xiang-Ning Feng
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Yang-Mu Huang
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China
- Institute for Global Health and Development, Peking University, Beijing, China
| | - Xian Xu
- Anhui Provincial Center for Disease Control and Prevention, Hefei, China
| | - Ying Chen
- Department of Global Health, School of Public Health, Peking University, Haidian District, 38 Xue Yuan Road, Beijing, 100191, China.
- Institute for Global Health and Development, Peking University, Beijing, China.
| | - Duo-Quan Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Shanghai, China.
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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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.
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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.
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Kua KP. Better health through better housing - Current impact and future prospects of randomized trials. Contemp Clin Trials 2023; 127:107114. [PMID: 36758933 DOI: 10.1016/j.cct.2023.107114] [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: 01/20/2023] [Revised: 02/04/2023] [Accepted: 02/05/2023] [Indexed: 02/10/2023]
Abstract
Safe and stable housing in integrated neighborhoods with access to basic amenities and social elements is indispensable for good health. Recent randomized controlled trials have demonstrated that improvements in the built environment have positive impacts on malaria, fall injuries, and gun violence outcomes. There are several challenges associated with performing studies that assess house improvement as an intervention for advancing human health and well-being, including ethical issues, lack of blinding, spillover effects, and differential behavior. Future research is warranted to evaluate the clinical benefits and cost-effectiveness of prototype houses or energyefficient prefabricated modular homes by employing more holistic strategies, such as integration of data analytics, peer support, and whole health coaching, addition of social contextual perspectives on mobile technology-supported community-based interventions, and combination of digital technology-informed community-engaged citizen science and participatory action programs with multi-sector partnerships. Gleaning stronger evidence from clinical trials and model-based economic analyses that ascertain the effects of multiple intersecting factors on individuals and communities would illuminate effective policymaking options in healthy housing and guide successful implementation of sustainable public health policies. Straightforward and cost-effective pathways should therefore be created based on highest-quality scientific data to lead the scaling up of novel housing interventions and capacity building for health-in-all-policies to support population health equity, thereby ensuring that everyone has access to housing and the chance to live a healthy and productive life.
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Affiliation(s)
- Kok Pim Kua
- Stanford University, Stanford, CA 94305, USA.
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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.
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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.
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9
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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.
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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
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10
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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.
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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
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11
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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
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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.
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12
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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.
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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
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13
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Mmbando AS, Bradley J, Kazimbaya D, Kasubiri R, Knudsen J, Siria D, von Seidlein L, Okumu FO, Lindsay SW. The effect of light and ventilation on house entry by Anopheles arabiensis sampled using light traps in Tanzania: an experimental hut study. Malar J 2022; 21:36. [PMID: 35123497 PMCID: PMC8818140 DOI: 10.1186/s12936-022-04063-3] [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: 10/14/2021] [Accepted: 01/26/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
In sub-Saharan Africa, house design and ventilation affects the number of malaria mosquito vectors entering houses. This study hypothesized that indoor light from a CDC-light trap, visible from outside a hut, would increase entry of Anopheles arabiensis, an important malaria vector, and examined whether ventilation modifies this effect.
Methods
Four inhabited experimental huts, each situated within a large chamber, were used to assess how light and ventilation affect the number of hut-entering mosquitoes in Tanzania. Each night, 300 female laboratory-reared An. arabiensis were released inside each chamber for 72 nights. Nightly mosquito collections were made using light traps placed indoors. Temperature and carbon dioxide concentrations were measured using data loggers. Treatments and sleepers were rotated between huts using a randomized block design.
Results
When indoor light was visible outside the huts, there was an 84% increase in the odds of collecting mosquitoes indoors (Odds ratio, OR = 1.84, 95% confidence intervals, 95% CI 1.74–1.95, p < 0.001) compared with when it was not. Although the odds of collecting mosquitoes in huts with closed eaves (OR = 0.54, 95% CI 0.41–0.72, p < 0.001) was less than those with open eaves, few mosquitoes entered either type of well-ventilated hut. The odds of collecting mosquitoes was 99% less in well-ventilated huts, compared with poorly-ventilated traditional huts (OR = 0.01, 95% CI 0.01–0.03, p < 0.001). In well-ventilated huts, indoor temperatures were 1.3 °C (95% CI 0.9–1.7, p < 0.001) cooler, with lower carbon dioxide (CO2) levels (mean difference = 97 ppm, 77.8–116.2, p < 0.001) than in poorly-ventilated huts.
Conclusion
Although light visible from outside a hut increased mosquito house entry, good natural ventilation reduces indoor carbon dioxide concentrations, a major mosquito attractant, thereby reducing mosquito-hut entry.
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