Background: Resistance of anopheline mosquitoes to pyrethroid insecticides is spreading rapidly across sub-Saharan Africa, diminishing the efficacy of insecticide-treated nets (ITNs) - the primary tool for preventing malaria. The entomological efficacy of indoor vector control interventions can be measured in experimental hut trials (EHTs), which are specially designed to quantify the protection provided under controlled conditions. Experimental hut structures resemble local housing but allow collection of surviving exiting mosquitoes as well as dead or dying mosquitoes. There is a need to understand how the spread of resistance changes ITN efficacy and to elucidate factors influencing EHT results, including differences in experimental hut construction and design features, to support the development of novel vector control tools. Methods: A comprehensive database of EHTs was compiled and summarised following a systematic review to identify all known trials investigating ITNs or indoor residual spraying (IRS) across sub-Saharan Africa. This analysis focuses on EHTs investigating ITNs and uses Bayesian statistical models to characterise the complex interaction between ITNs and mosquitoes, the variability between studies, and the impact of pyrethroid resistance. Results: As resistance rises, the entomological efficacy of ITNs declines. They induce less mortality and are less likely to deter mosquitoes from entering huts. Despite this, ITNs continue to offer considerable personal protection by reducing mosquito feeding until resistance reaches high levels. There are clear associations between the different entomological impacts of ITNs, though there is still substantial variability between studies, some of which can be accounted for by hut design. The relationship between EHT outcomes and the level of resistance (as measured by discriminating dose bioassays) is highly uncertain. Conclusions: The meta-analyses show that EHTs are an important reproducible assay for capturing the complex entomological efficacy of ITNs on blood-feeding mosquitoes. The impact of pyrethroid resistance on these measures appears broadly consistent across a wide geographical area once hut design is accounted for, suggesting results can be extrapolated beyond the sites where the trials were conducted. Further work is needed to understand factors influencing EHT outcomes and how the relationship between outcomes and resistance varies when different methods are used to assess the level of resistance in wild mosquito populations. This will allow more precise estimates of the efficacy of these important vector control tools.

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Measuring COVID-19 spread remains challenging in many countries due to testing limitations. In Java, reported cases and deaths increased throughout 2020 despite intensive control measures, particularly within Jakarta and during Ramadan. However, underlying trends are likely obscured by variations in case ascertainment. COVID-19 protocol funerals in Jakarta provide alternative data indicating a substantially higher burden than observed within confirmed deaths. Transmission estimates using this metric follow mobility trends, suggesting earlier and more sustained intervention impact than observed in routine data. Modelling suggests interventions have lessened spread to rural, older communities with weaker healthcare systems, though predict healthcare capacity will soon be exceeded in much of Java without further control. Our results highlight the important role syndrome-based measures of mortality can play in understanding COVID-19 transmission and burden.