背景:2017年,在比科岛上建造了几个新的住房区,赤道几内亚。本案例研究评估了建设项目对蚊子幼虫栖息地的影响以及幼虫源管理在降低周边地区疟疾病媒密度方面的有效性。
方法:在11个新的建筑工地,通过包含按蚊的幼虫栖息地和晚龄幼虫期的比例来评估按蚊幼虫的存在。以色列苏云金芽孢杆菌(Bti)杀幼剂每周应用于9个地点,持续30周,而两个地方没有收到杀幼虫,并作为对照。通过六个建筑工地邻近社区的人类登陆收集物监测成年蚊子密度,包括两个控制地点。
结果:接受Bti的站点对两种p的观察率都显着降低(3.2%vs.18.0%;p<0.001)和晚龄按蚊。蚊子(14.1vs.43.6%;p<0.001)与两个未处理的位点相比。按蚊。占人类登陆收集物收集的蚊子的67%,与未经处理的地点相比,在处理过的建筑工地附近的社区中捕获的蚊子的水平明显较低(p<0.001),估计人类咬伤率降低38%(IRR:0.62,95%CIIRR:0.55,0.69)。研究开始七个月后,未经治疗的部位因伦理问题而接受治疗,需要立即申请Bti。接下来的一周,栖息地的数量,幼虫部位与按蚊的比例。蛹,晚年,与这些地点相邻的社区中的成人咬人率都下降到所有地点的可比水平。
结论:研究结果表明,幼虫源管理是在基础设施发展过程中抑制蚊子种群的有效干预措施。将幼虫源管理纳入正在进行和计划中的建设计划中,代表了一个机会,可以根据人为遗传变化对媒介控制进行微调。理想情况下,这应该成为疟疾流行地区的标准做法,以减少作为建筑常见副产品的活蚊子栖息地。
BACKGROUND: In 2017, several new housing districts were constructed on Bioko Island, Equatorial Guinea. This
case study assessed the impact construction projects had on mosquito larval habitats and the effectiveness of larval source management in reducing malaria vector density within the surrounding area.
METHODS: Anopheline larval presence was assessed at 11 new construction sites by the proportion of larval habitats containing Anopheline pupae and late instar larval stages. Bacillus thuringiensis israelensis (Bti) larvicide was applied weekly to nine locations for 30 weeks, while two locations received no larvicide and acted as controls. Adult mosquito density was monitored via human landing collections in adjacent communities of six construction sites, including the two control sites.
RESULTS: The sites that received Bti had significantly lower observation rates of both pupae (3.2% vs. 18.0%; p < 0.001) and late instar Anopheles spp. mosquitoes (14.1 vs. 43.6%; p < 0.001) compared to the two untreated sites. Anopheles spp. accounted for 67% of mosquitoes collected with human landing collections and were captured at significantly lower levels in communities adjacent to treated construction sites compared to untreated sites (p < 0.001), with an estimated 38% reduction in human biting rate (IRR: 0.62, 95% CI IRR: 0.55, 0.69). Seven months after the start of the study, untreated sites were treated due to ethical concerns given results from treatment sties, necessitating immediate Bti application. The following week, the number of habitats, the proportion of larval sites with Anopheles spp. pupae, late instars, and adult biting rates in adjacent communities to these sites all decreased to comparable levels across all sites.
CONCLUSIONS: Findings suggest larval source management represents an effective intervention to suppress mosquito populations during infrastructure development. Incorporating larval source management into ongoing and planned construction initiatives represents an opportunity to fine tune vector control in response to anthropogenetic changes. Ideally, this should become standard practice in malaria-endemic regions in order to reduce viable mosquito habitats that are common by-products of construction.