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bioRxiv · 10.1101/435438

Malaria control dynamics may explain inconsistent outcomes from bednet trials: a modeling study

Orsborne, J.·Walker, T.·Yakob, L.
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Abstract

BACKGROUNDLong-lasting insecticidal bednets have unparalleled efficacy in reducing malaria burden. However, insecticidal resistance and bednet avoidance behaviors among the mosquito vectors are now widespread.\n\nMETHODSReviewing the relevant field and semi-field studies highlights the ubiquity of zoophagic and spatiotemporal (biting outdoors or at different times of day) plasticity among vectors in response to bednet deployment. Transmission models coupled with the population genetics of vectors are developed to assess the impact on malaria control caused by insecticide resistance and the avoidance behaviors of mosquitoes.\n\nRESULTSInteractions between physiological resistance and behavioral resilience among mosquito vectors can significantly impact malaria control efforts both in the short- and long-term. The possibility of misleading observations from injudiciously timed assessments of malaria control programs is demonstrated through simulation.\n\nCONCLUSIONSCurrently, there are no guidelines to inform when during a bednet trial its effectiveness should be measured. The importance of this oversight is described in the context of recent randomized controlled bednet trials.

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Orsborne, J., Walker, T., Yakob, L.. 2018-10-04. Malaria control dynamics may explain inconsistent outcomes from bednet trials: a modeling study. https://doi.org/10.1101/435438

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