Observational studyBMJ global health2023
Using routine health data to evaluate the impact of indoor residual spraying on malaria transmission in Madagascar.
Observational study in BMJ global health, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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The trial behind it
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Who cites it
14 citing papers in PubMed, 19 citations in OpenAlex.
- Trial
- Effects of Drug Resistance on the Global Spread of Malaria: A Systematic Literature Review.Health science reports · 2026Review
- The Malaria Vaccine Implementation Programme reduced clinical malaria in Kenya, 2020 to 2022 : Impact evaluation with predictive time-series models of routine surveillance data.Malaria journal · 2026Article
- Impact of indoor residual spraying and insecticide-treated nets on malaria burden in 8 districts in West Nile and Acholi regions, Uganda: a quasi-experimental study.BMC global and public health · 2026Article
- Understanding inequities in the malaria landscape of Madagascar: a scoping review of current evidence.Malaria journal · 2026Review
- Assessing the effectiveness of seasonal malaria chemoprevention on malaria burden among children under 5 in northern Benin: a statistical modelling approach.BMJ public health · 2026Article
- Epidemiology of Malaria in Northern Madagascar as Exemplified by the Mampikony District.Pathogens (Basel, Switzerland) · 2025Article
- Public health surveillance of tropical diseases in Madagascar: a scoping review of population burden, intervention strategies, and health system responses.BMC public health · 2025Article
- Testing indoor residual spraying coverage targets for malaria control, Bioko, Equatorial Guinea.Bulletin of the World Health Organization · 2025Article
- Reconsidering indoor residual spraying coverage targets: A retrospective analysis of high-resolution programmatic malaria control data.Proceedings of the National Academy of Sciences of the United States of America · 2025Article
- Process and Methodological Considerations for Observational Analyses of Vector Control Interventions in Sub-Saharan Africa Using Routine Malaria Data.The American journal of tropical medicine and hygiene · 2025Article
- Cost of the national malaria control program and cost-effectiveness of indoor residual spraying and insecticide-treated bed net interventions in two districts of Madagascar.Cost effectiveness and resource allocation : C/E · 2024Article
- Analysis of the 24-h biting patterns and human exposures to malaria vectors in south-eastern Tanzania.Parasites & vectors · 2024Article
- Observational
Corrections and comments
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Authors and funding
12 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
introductionIndoor residual spraying (IRS) and insecticide-treated bed nets (ITNs) are cornerstone malaria prevention methods in Madagascar. This retrospective observational study uses routine data to evaluate the impacts of IRS overall, sustained IRS exposure over multiple years and level of spray coverage (structures sprayed/found) in nine districts where non-pyrethroid IRS was deployed to complement standard pyrethroid ITNs from 2017 to 2020.
methodsMultilevel negative-binomial generalised linear models were fit to estimate the effects of IRS exposure overall, consecutive years of IRS exposure and spray coverage level on monthly all-ages population-adjusted malaria cases confirmed by rapid diagnostic test at the health facility level. The study period extended from July 2016 to June 2021. Facilities with missing data and non-geolocated communes were excluded. Facilities in IRS districts were matched with control facilities by propensity score analysis. Models were controlled for ITN survivorship, mass drug administration coverage, precipitation, enhanced vegetation index, seasonal effects and district. Predicted cases under a counterfactual
resultsExposure to IRS overall reduced case incidence by an estimated 30.3% from 165.8 cases per 1000 population (95% CI=139.7 to 196.7) under a counterfactual no IRS scenario, to 114.3 (95% CI=96.5 to 135.3) over 12 months post-IRS campaign in nine districts. A third year of IRS reduced malaria cases 30.9% more than a first year (incidence rate ratio (IRR)=0.578, 95% CI=0.578 to 0.825, p<0.001) and 26.7% more than a second year (IRR=0.733, 95% CI=0.611 to 0.878, p=0.001). There was no significant difference between the first and second year (p>0.05). Coverage of 86%-90% was associated with a 19.7% reduction in incidence (IRR=0.803, 95% CI=0.690 to 0.934, p=0.005) compared with coverage ≤85%, although these results were not robust to sensitivity analysis.
conclusionThis study demonstrates that non-pyrethroid IRS appears to substantially reduce malaria incidence in Madagascar and that sustained implementation of IRS over three years confers additional benefits.
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