MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
Nuffield Department of Primary Care Health Science, University of Oxford, Oxford, UK.
Malar J. 2021 Mar 17;20(1):151. doi: 10.1186/s12936-021-03684-4.
Attractive targeted sugar baits (ATSBs) are a promising new tool for malaria control as they can target outdoor-feeding mosquito populations, in contrast to current vector control tools which predominantly target indoor-feeding mosquitoes.
It was sought to estimate the potential impact of these new tools on Plasmodium falciparum malaria prevalence in African settings by combining data from a recent entomological field trial of ATSBs undertaken in Mali with mathematical models of malaria transmission. The key parameter determining impact on the mosquito population is the excess mortality due to ATSBs, which is estimated from the observed reduction in mosquito catch numbers. A mathematical model capturing the life cycle of P. falciparum malaria in mosquitoes and humans and incorporating the excess mortality was used to estimate the potential epidemiological effect of ATSBs.
The entomological study showed a significant reduction of ~ 57% (95% CI 33-72%) in mosquito catch numbers, and a larger reduction of ~ 89% (95% CI 75-100%) in the entomological inoculation rate due to the fact that, in the presence of ATSBs, most mosquitoes do not live long enough to transmit malaria. The excess mortality due to ATSBs was estimated to be lower (mean 0.09 per mosquito per day, seasonal range 0.07-0.11 per day) than the bait feeding rate obtained from one-day staining tests (mean 0.34 per mosquito per day, seasonal range 0.28-0.38 per day).
From epidemiological modelling, it was predicted that ATSBs could result in large reductions (> 30% annually) in prevalence and clinical incidence of malaria, even in regions with an existing high malaria burden. These results suggest that this new tool could provide a promising addition to existing vector control tools and result in significant reductions in malaria burden across a range of malaria-endemic settings.
有吸引力的靶向糖饵（ATSBs）是一种有前途的疟疾控制新工具，因为它们可以针对户外觅食的蚊子种群，而不是目前主要针对室内觅食蚊子的病媒控制工具。
我们试图通过结合在马里进行的最近的 ATSB 昆虫学实地试验数据和疟疾传播的数学模型，来估计这些新工具对非洲地区间日疟原虫疟疾流行率的潜在影响。决定对蚊子种群影响的关键参数是由于 ATSB 而导致的过度死亡率，这是从观察到的蚊子捕获数量减少中估算出来的。一个捕获蚊子和人类间日疟原虫生命周期并纳入过度死亡率的数学模型，用于估计 ATSB 的潜在流行病学效应。
该昆虫学研究表明，蚊子捕获数量显著减少了约 57%（95%CI 33-72%），由于事实上，在有 ATSB 的情况下，大多数蚊子没有足够长的寿命来传播疟疾，昆虫接种率也出现了更大的减少，约 89%（95%CI 75-100%）。由于 ATSB 而导致的过度死亡率估计低于（每天每只蚊子 0.09 只，季节性范围为每天 0.07-0.11 只），从为期一天的染色试验中获得的诱饵摄食率（每天每只蚊子 0.34 只，季节性范围为每天 0.28-0.38 只）。
从流行病学模型预测，即使在疟疾负担已经很高的地区，ATSB 也可以导致疟疾流行率和临床发病率大幅下降（每年超过 30%）。这些结果表明，这种新工具可以为现有的病媒控制工具提供有希望的补充，并在一系列疟疾流行地区显著降低疟疾负担。
