背景:不相容性昆虫技术(IIT)与不育昆虫技术(SIT)相结合,通过释放不育雄性Wolbachia感染的蚊子,是控制伊蚊传播疾病的有希望的工具。然而,关于IIT-SIT对蚊子丰度的抑制作用的现实证据仍然主要限于在较短的试验持续时间内的半农村小村庄和郊区地区。然而,很大一部分伊蚊传播疾病发生在密集,城市,和高层位置,限制了以前研究对这些高疾病负担环境的适用性。这项技术多年来的可持续性和使用也是未知的。
方法:在这项综合对照研究中,我们进行了大规模的,针对埃及伊蚊的IIT-SIT在新加坡高层公共住宅区中的现场试验,赤道城邦.定期收集大量数据,全国监测系统的57990个独特的蚊子诱捕器,结合一组高维度的人为和环境混杂因素,我们收集了蚊子的丰度及其关键驱动因素。选择了四个乡镇作为干预组(截至2022年,人口规模约为607872名居民),其中在研究期间进行了将ITT与SIT相结合的干预措施。乡镇每周两次释放wAlbB-SG雄性埃及伊蚊。在流行病学周(EW)的过程中评估数据,提供记录的Wolbachia释放时间表和蚊子丰度数据的最佳时间分辨率。然后开发了一个新的综合控制框架,以说明干预措施在试验部门的非随机和交错采用设置,以确定IIT-SIT对女性埃及伊蚊种群的直接抑制作用。非释放区域的溢出效应,以及干预对其他蚊子种群如白纹伊蚊的影响。此外,我们根据日历时间重新计算了有效性,自干预以来的时间,并在多个站点上检查IIT-SIT有效性的异质性。
结果:在EW272018和EW262022之间,Wolbachia发布了117个部门,其中97个有足够的陷阱数据,这是在2019年EW8和2022年EW26之间收集的。我们发现,基于Wolbachia的IIT-SIT在3个月内平均减少了野生型雌性A埃及伊蚊种群62·01%(95%CI60·68至63·26),到6个月,78·40%(77·56至79·18),和91·32%(90·95至91·66),至少18个月的释放。我们还发现了一个较小但不可忽视的溢出抑制作用,随着时间的推移逐渐增加(平均溢出干预有效性61·02%[95%CI57·89至63·72],非干预部门)。尽管Wolbachia释放后,四个干预乡镇的白纹伊蚊种群没有一致的变化,所有释放部门对白纹伊蚊种群的平均干预效果为-25·80%(95%CI-30·93至-21·05),这是由两个城镇的增长推动的。
结论:我们的结果表明IIT-SIT具有增强长期,热带城市的大规模病媒控制,登革热负担最大的地方。应在今后的工作中评估这些干预措施在不同地理环境中的效果。
背景:新加坡财政部,可持续发展与环境部,国家环境局,国家机器人项目。
BACKGROUND: Incompatible insect technique (IIT) coupled with sterile insect technique (SIT) via the release of sterile male Wolbachia-infected mosquitoes is a promising tool for Aedes-borne disease control. Yet, real-world evidence on the suppressive effectiveness of IIT-SIT on mosquito abundance remains mostly limited to small semi-rural village and suburban localities over short
trial durations. However, a large proportion of Aedes-borne diseases occur in dense, urban, and high-rise locations, limiting the applicability of previous studies for these settings with high disease burden. The sustainability and use of this technology over multiple years is also unknown.
METHODS: In this synthetic control
study, we conducted a large-scale, field
trial of IIT-SIT targeting Aedes aegypti among high-rise public housing estates in Singapore, an equatorial city state. Routinely collected data from a large, nationwide surveillance system of 57 990 unique mosquito traps, combined with a high-dimensional set of anthropogenic and environmental confounders were collected to ascertain mosquito abundance and its key drivers. Four townships were selected as the intervention groups (approximate population size of 607 872 residents as of 2022), wherein interventions that combined ITT with SIT over the course of the
study period were conducted. Townships were subject to releases of wAlbB-SG male A aegypti mosquitoes twice a week. Data were assessed over the course of epidemiological weeks (EWs), which provide the finest temporal resolution of recorded Wolbachia release schedule and mosquito abundance data. A novel synthetic control framework was then developed to account for the non-randomised and staggered adoption setting of the intervention across
trial sectors to identify the direct suppressive effectiveness of IIT-SIT on female A aegypti populations, the spillover effects in non-release areas, and the effect of the intervention on other mosquito populations such as Aedes albopictus. Furthermore, we recalculated effectiveness in terms of calendar time, time since intervention, and over multiple sites to examine heterogeneities in IIT-SIT effectiveness.
RESULTS: Between EW27 2018 and EW26 2022, Wolbachia releases were conducted across 117 sectors, of which 97 had sufficient trap data, which were collected between EW8 2019 and EW26 2022. We found that Wolbachia-based IIT-SIT reduced wild-type female A aegypti populations by a mean of 62·01% (95% CI 60·68 to 63·26) by 3 months, 78·40% (77·56 to 79·18) by 6 months, and 91·32% (90·95 to 91·66) by at least 18 months of releases. We also found a smaller but non-negligible spillover suppression effect that gradually increased over time (mean spillover intervention effectiveness 61·02% [95% CI 57·89 to 63·72] in adjacent, non-intervention sectors). Although no consistent change in A albopictus populations was seen across the four intervention townships after Wolbachia releases, the average intervention effectiveness on the A albopictus population across all release sectors was -25·80% (95% CI -30·93 to -21·05), which was driven by increases in two towns.
CONCLUSIONS: Our results demonstrate the potential of IIT-SIT for strengthening long-term, large-scale vector control in tropical cities, where dengue burden is the greatest. The effect of these interventions in different geographical settings should be assessed in future work.
BACKGROUND: Singapore\'s Ministry of Finance, Ministry of Sustainability and the Environment, National Environment Agency, and National Robotics Program.