Guagliardo Sarah Anne, Barboza José Luis, Morrison Amy C, Astete Helvio, Vazquez-Prokopec Gonzalo, Kitron Uriel
Department of Environmental Sciences, Emory University, Atlanta, Georgia, United States of America.
Universidad Nacional de la Amazonía Peruana, Iquitos, Peru.
PLoS Negl Trop Dis. 2014 Aug 7;8(8):e3033. doi: 10.1371/journal.pntd.0003033. eCollection 2014 Aug.
In the Peruvian Amazon, the dengue vector Aedes aegypti is abundant in large urban centers such as Iquitos. In recent years, it has also been found in a number of neighboring rural communities with similar climatic and socioeconomic conditions. To better understand Ae. aegypti spread, we compared characteristics of communities, houses, and containers in infested and uninfested communities.
We conducted pupal-demographic surveys and deployed ovitraps in 34 communities surrounding the city of Iquitos. Communities surveyed were located along two transects: the Amazon River and a 95 km highway. We calculated entomological indices, mapped Ae. aegypti presence, and developed univariable and multivariable logistic regression models to predict Ae. aegypti presence at the community, household, or container level.
Large communities closer to Iquitos were more likely to be infested with Ae. aegypti. Within infested communities, houses with Ae. aegypti had more passively-filled containers and were more often infested with other mosquito genera than houses without Ae. aegypti. For containers, large water tanks/drums and containers with solar exposure were more likely to be infested with Ae. aegypti. Maps of Ae. aegypti presence revealed a linear pattern of infestation along the highway, and a scattered pattern along the Amazon River. We also identified the geographical limit of Ae. aegypti expansion along the highway at 19.3 km south of Iquitos.
In the Peruvian Amazon, Ae. aegypti geographic spread is driven by human transportation networks along rivers and highways. Our results suggest that urban development and oviposition site availability drive Ae. aegypti colonization along roads. Along rivers, boat traffic is likely to drive long-distance dispersal via unintentional transport of mosquitoes on boats.
在秘鲁亚马逊地区，登革热媒介埃及伊蚊在伊基托斯等大型城市中心大量存在。近年来，在一些气候和社会经济条件相似的邻近农村社区也发现了这种蚊子。为了更好地了解埃及伊蚊的传播情况，我们比较了受感染社区和未受感染社区的社区、房屋及容器的特征。
我们在伊基托斯市周边的34个社区进行了蛹种群调查并设置了诱蚊产卵器。被调查的社区分布在两条样带上：亚马逊河和一条95公里长的公路。我们计算了昆虫学指标，绘制了埃及伊蚊的分布地图，并建立了单变量和多变量逻辑回归模型，以预测埃及伊蚊在社区、家庭或容器层面的存在情况。
距离伊基托斯较近的大型社区更有可能受到埃及伊蚊的感染。在受感染的社区中，有埃及伊蚊的房屋比没有埃及伊蚊的房屋有更多被动积水容器，并且更常被其他蚊属感染。对于容器来说，大型水箱/水桶以及暴露在阳光下的容器更有可能被埃及伊蚊感染。埃及伊蚊分布地图显示，沿公路呈线性分布模式，沿亚马逊河呈分散分布模式。我们还确定了埃及伊蚊沿公路向南扩展的地理极限在伊基托斯以南19.3公里处。
在秘鲁亚马逊地区，埃及伊蚊的地理传播是由河流和公路沿线的人类交通网络推动的。我们的研究结果表明，城市发展和产卵场所的可用性推动了埃及伊蚊沿道路的定殖。在河流沿线，船只交通可能通过无意间在船上运输蚊子而推动远距离扩散。
