Abstract Insecticide-treated nets (ITNs) are most effective against malaria if mosquitoes attempt to bite people when they are in bed. Collecting the biting behaviour data required to quantify a key metric - the proportion of bites taken when people are in bed - is challenging. We tested the reliability of a simplified mosquito sampling method against data from a published systematic review. Using the methodology in the remote, malaria-endemic Bijagos archipelago, Guinea-Bissau, we estimate this proportion is 0.95 (95% Credible intervals, CrI: 0.84, 1.00). Transmission modelling suggests that pyrethroid-only ITNs in a Bijagos-like setting could avert 86% of Plasmodium falciparum clinical cases in under 5-year-olds (95% CrI: 77, 89%), compared to without ITNs. Due to agricultural work, some islanders sleep without ITNs in temporary outdoor shelters, potentially reducing the predicted population-level impact of ITNs by 35%. Our methodology increases the feasibility of monitoring the impact of indoor malaria control interventions in resource-limited settings.
Chandradeva et al. (Tue,) studied this question.