Jacobi C A, Enyong P, Renz A
Tropenmedizinisches Institut der Universität Tübingen, Wilhelmstrasse 27, D-72074 Tübingen, Germany.
Parasit Vectors. 2010 Jun 18;3:53. doi: 10.1186/1756-3305-3-53.
Onchocerca volvulus, the causative agent of river blindness, is transmitted through the black fly Simulium damnosum s.l., which breeds in turbulent river waters. To date, the number of flies attacking humans has only been determined by standard fly collectors near the river or the village. In our study, we counted the actual number of attacking and successfully feeding S. damnosum s.l. flies landing on individual villagers during their routine day-time activities in two villages of the Sudan-savannah and rainforest of Cameroon. We compared these numbers to the number of flies caught by a standard vector-collector, one positioned near the particular villager during his/her daily activity and the other sitting at the nearest Simulium breeding site.
Using these data obtained by the two vector-collectors, we were able to calculate the Actual Index of Exposure (AIE). While the AIE in the savannah was on average 6,3%, it was 34% in the rainforest. The Effective Annual Transmission Potential (EATP) for individual villagers was about 20 fold higher in the rainforest compared to the savannah.
Here we show for the first time that it is possible to determine the EATP. Further studies with more subjects are needed in the future. These data are important for the development of future treatment strategies.
盘尾丝虫是河盲症的病原体，通过在湍急河水中繁殖的黑蝇蚋（Simulium damnosum s.l.）传播。迄今为止，攻击人类的黑蝇数量仅通过河流或村庄附近的标准捕蝇器来确定。在我们的研究中，我们统计了在喀麦隆苏丹草原和雨林的两个村庄中，村民日常白天活动期间落在个体村民身上的正在攻击和成功吸血的蚋的实际数量。我们将这些数量与标准病媒捕集器捕获的苍蝇数量进行了比较，一个在特定村民日常活动期间放置在其附近，另一个放置在最近的蚋繁殖地点。
利用两个病媒捕集器获得的数据，我们能够计算实际暴露指数（AIE）。在草原地区，AIE平均为6.3%，而在雨林地区为34%。与草原地区相比，雨林地区个体村民的有效年传播潜力（EATP）高出约20倍。
我们首次表明可以确定EATP。未来需要对更多受试者进行进一步研究。这些数据对未来治疗策略的制定很重要。
