Department of Entomology, Center for Infectious Disease Dynamics, Pennsylvania State University, University Park, PA, USA.
Sightsavers - Yaoundé, Cameroon; Haywards Heath, UK.
Int Health. 2024 May 1;16(3):351-356. doi: 10.1093/inthealth/ihad066.
Human landing catches (HLCs) are required to collect blackflies for entomological evaluation to verify onchocerciasis elimination. However, there are ethical concerns regarding exposure of vector collectors to infectious blackflies and safer alternative methods are needed. This study evaluated a modified HLC technique where collectors wore coloured trousers (blue, black or blue-black), protecting them from bites during fly collection, and their performance was compared with the standard.
The study was conducted in Makouopsap, Cameroon, in the Massangam health district for 4 months. Four collector pairs-one 'standard' (bare-legged) and three modified-were placed 50 m apart along known breeding sites on the Mbam and Nja Rivers. Collections were performed from 07:00 to 17:00 h, 4 d/month. Hourly rates of flies caught were analysed using a negative binomial generalised linear model to explore associations between flies caught and collection techniques and seasons.
Overall, 17 246 blackflies were caught. There was no significant statistical difference in the number of blackflies and parous flies caught between black trousers and the standard. Thus there is a strong indication that wearing black trousers is a viable non-inferior alternative to the standard HLC.
Further studies are needed to confirm generalisability in different ecozones and transmission environments and among different blackfly species.
为了进行昆虫学评估以验证盘尾丝虫病的消除情况，需要进行人体着陆捕获（HLC）以收集采采蝇。然而，采集者接触传染性采采蝇会引发伦理问题，因此需要更安全的替代方法。本研究评估了一种改良的 HLC 技术，即采集者穿着彩色长裤（蓝色、黑色或蓝黑色），在采集飞蝇时可免受叮咬，将其与标准 HLC 进行了比较。
本研究在喀麦隆马库奥普萨的马桑加姆卫生区进行，为期 4 个月。沿着姆巴姆河和恩贾河已知的繁殖地，每 50 米放置一对采集者，其中一对是“标准”（赤脚），另外三对是改良的。采集时间为每天 07:00 至 17:00，每月 4 天。使用负二项广义线性模型分析每小时捕获的飞蝇数量，以探讨捕获飞蝇与采集技术和季节之间的关联。
共捕获了 17246 只采采蝇。黑裤和标准 HLC 之间捕获的采采蝇和产卵采采蝇数量没有统计学上的显著差异。因此，强烈表明穿黑裤是标准 HLC 的可行非劣效替代方法。
需要进一步研究以确认在不同生态区和传播环境以及不同采采蝇物种中的可推广性。
