Burton Timothy A, Syahrani Lepa, Permana Dendi Hadi, Rozi Ismail Ekoprayitno, Risandi Rifqi, Zubaidah Siti, Zulfah Syarifah, Maloha Ma'as M, Efendi Rusli, Kristiana Maria, Asih Puji B S, Syafruddin Din, Lobo Neil F
Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA.
Eijkman Research Center for Molecular Biology, National Research and Innovation Agency (BRIN), Cibinong, Indonesia.
Malar J. 2025 Apr 10;24(1):118. doi: 10.1186/s12936-025-05284-y.
Interventions against adult Anopheles mosquitoes responsible for malaria transmission have traditionally been aimed at indoor spaces and biting behaviours. However, no globally recommended intervention exists which directly interrupt or target outdoor biting behaviours. A volatile pyrethroid spatial emanator (SE) containing transfluthrin aims to address this gap in protection via a simple-to-use, readily deployable device to provide multiple weeks of protection. The device was tested in open-walled households of the forest-dwelling Orang Rimba people in Sumatra, Indonesia, over the course of sixteen weekly entomological visits.
Double-net traps were used for all mosquito collections. Collections occurred near Bukit Duabelas National Park in central Sumatra, an area characterized by secondary forests undergoing widespread conversion to palm and rubber plantations. Four collections occurred per collection night within ten geographically separated small familial groups for a total of 40 trap-nights per week. Groups were assigned the SE or a control device after a seven-week baseline trapping period. Devices were replaced every four weeks. Results were compared using generalized linear models, incorporating treatment, weather, and landscape parameters as fixed effects, with date and location included as random effects.
Anopheles mosquitoes were captured on 63.2% of all collection nights. Overall nightly Anopheles host-seeking activity was lower in the presence of SE devices (RR: 0.29 [0.19-0.45], p < 0.001). Non-Anopheles mosquitoes experienced a smaller nightly decline in behaviour (RR: 0.78 [0.64-0.93], p = 0.007). The age of the device (1 month) did not impact modeled efficacy. Anopheles host-seeking activity was also positively correlated with humidity, topographic wetness, and local human structure density.
The SE device evaluated in this field trial was effective in reducing outdoor human exposure to Anopheles and non-Anopheles mosquito host-seeking activity. The effect was not found to depend upon the age of the device, suggesting that the protection was persistent over the 4-week replacement period during this study. There was an association between hour of collection and intervention efficacy, suggesting the possibility of species-specific effects which were not further investigated. The SE device is a promising, low-cost, easily deployable, and distributable intervention that reduces exposure to mosquitoes with consequent impacts on transmission in outdoor environments.
传统上，针对传播疟疾的成年按蚊的干预措施主要针对室内空间和叮咬行为。然而，目前尚无全球推荐的直接阻断或针对户外叮咬行为的干预措施。一种含有四氟甲醚菊酯的挥发性拟除虫菊酯空间散发器（SE）旨在通过一种简单易用、易于部署的设备来填补这一保护空白，提供数周的保护。在印度尼西亚苏门答腊岛森林居住的奥兰 Rimba 族的开放式房屋中，经过十六次每周一次的昆虫学访问，对该设备进行了测试。
所有蚊子采集均使用双层网捕蚊器。采集地点位于苏门答腊岛中部的布基杜阿贝拉斯国家公园附近，该地区以次生林为主，正广泛转变为棕榈和橡胶种植园。在十个地理上分开的小家庭组内，每个采集夜晚进行四次采集，每周总共 40 个诱捕夜。在为期七周的基线诱捕期后，将这些组分配使用 SE 设备或对照设备。设备每四周更换一次。使用广义线性模型比较结果，将处理、天气和景观参数作为固定效应纳入，日期和地点作为随机效应。
在所有采集夜晚中，63.2% 的夜晚捕获到了按蚊。在有 SE 设备的情况下，总体夜间按蚊寻找宿主活动较低（相对风险：0.29 [0.19 - 0.45]，p < 0.001）。非按蚊的夜间行为下降幅度较小（相对风险：0.78 [0.64 - 0.93]，p = 0.007）。设备使用时长（1 个月）对模拟效果没有影响。按蚊寻找宿主活动也与湿度、地形湿度和当地人类建筑密度呈正相关。
在该现场试验中评估的 SE 设备有效地减少了户外人类接触按蚊和非按蚊寻找宿主的活动。未发现效果取决于设备的使用时长，这表明在本研究的 4 周更换期内保护效果持续存在。采集时间与干预效果之间存在关联，这表明可能存在物种特异性效应，但未作进一步研究。SE 设备是一种有前景的、低成本、易于部署和分发的干预措施，可减少接触蚊子的机会，从而对户外环境中的传播产生影响。
