The impact of pyrethroid resistance on the efficacy and effectiveness of bednets for malaria control in Africa
Abstract
Long lasting pyrethroid treated bednets are the most important tool for preventing malaria. Pyrethroid resistant Anopheline mosquitoes are now ubiquitous in Africa though the public health impact remains unclear, impeding the deployment of more expensive nets. Meta-analyses of bioassay studies and experimental hut trials are used to characterise how pyrethroid resistance changes the efficacy of standard bednets, and those containing the synergist piperonyl butoxide (PBO), and assess its impact on malaria control. New bednets provide substantial personal protection until high levels of resistance though protection may wane faster against more resistant mosquito populations as nets age. Transmission dynamics models indicate that even low levels of resistance would increase the incidence of malaria due to reduced mosquito mortality and lower overall community protection over the life-time of the net. Switching to PBO bednets could avert up to 0.5 clinical cases per person per year in some resistance scenarios.
Data availability
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Data from: The impact of pyrethroid resistance on the efficacy and effectiveness of bednets for malaria control in AfricaAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
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Funding
Medical Research Council
- Thomas S Churcher
Department for International Development
- Thomas S Churcher
European Research Council
- Hilary Ranson
Innovative Vector Control Consortium
- Thomas S Churcher
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Churcher et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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Modelling the effectiveness of bednets against mosquitoes and malaria.
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- Epidemiology and Global Health
- Microbiology and Infectious Disease
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