Department of Parasitology and Entomology, Kilimanjaro Christian Medical University College, Moshi, Tanzania.
Department of Allied Health Sciences, School of Health and Medical Sciences, The State University of Zanzibar, Zanzibar, Tanzania.
PLoS Negl Trop Dis. 2020 Dec 7;14(12):e0008949. doi: 10.1371/journal.pntd.0008949. eCollection 2020 Dec.
In Zanzibar, little is known about the arboviral disease vector Aedes aegypti in terms of abundance, spatio-temporal distribution of its larval habitats or factors associated with its proliferation. Effective control of the vector requires knowledge on ecology and habitat characteristics and is currently the only available option for reducing the risk of arboviral epidemics in the island nation of Zanzibar.
We conducted entomological surveys in households and surrounding compounds from February to May 2018 in the urban (Mwembemakumbi and Chumbuni) and rural (Chuini and Kama) Shehias (lowest government administrative unit) situated in the Urban-West region of Unguja island, Zanzibar. Larvae and pupae were collected, transported to the insectary, reared to adult, and identified to species level. Characteristics and types of water containers were also recorded on site. Generalized linear mixed models with binomial and negative binomial distributions were applied to determine factors associated with presence of Ae. aegypti immatures (i.e. both larvae and pupae) or pupae, alone and significant predictors of the abundance of immature Ae. aegypti or pupae, respectively.
The survey provided evidence of widespread presence and abundance of Ae. aegypti mosquitoes in both urban and rural settings of Unguja Island. Interestingly, rural setting had higher numbers of infested containers, all immatures, and pupae than urban setting. Likewise, higher House and Breteau indices were recorded in rural compared to the urban setting. There was no statistically significant difference in Stegomyia indices between seasons across settings. Plastics, metal containers and car tires were identified as the most productive habitats which collectively produced over 90% of all Ae. aegypti pupae. Water storage, sun exposure, vegetation, and organic matter were significant predictors of the abundance of immature Ae. aegypti.
Widespread presence and abundance of Ae. aegypti were found in rural and urban areas of Unguja, the main island of Zanzibar. Information on productive habitats and predictors of colonization of water containers are important for the development of a routine Aedes surveillance system and targeted control interventions in Zanzibar and similar settings.
在桑给巴尔，关于病媒埃及伊蚊的丰度、幼虫栖息地的时空分布以及与蚊媒滋生相关的因素知之甚少。这种病媒的有效控制需要了解其生态和生境特征，而这也是降低桑给巴尔这个岛国发生虫媒病毒病风险的唯一可行选择。
我们于 2018 年 2 月至 5 月期间在桑给巴尔 Unguja 岛西部城市（Mwembemakumbi 和 Chumbuni）和农村（Chuini 和 Kama）Shehias（最低级别的政府行政单位）的家庭及其周边场所进行了昆虫学调查。收集幼虫和蛹，将其运往昆虫饲养室进行饲养，并将其鉴定到种的水平。还在现场记录了各种类型的储水容器的特征。应用二项式和负二项式分布的广义线性混合模型来确定与埃及伊蚊幼虫（即幼虫和蛹）或蛹存在相关的因素，以及分别预测埃及伊蚊幼虫或蛹丰度的显著预测因子。
调查结果表明，埃及伊蚊蚊子在 Unguja 岛的城市和农村地区广泛存在和大量滋生。有趣的是，与城市环境相比，农村环境中受感染的容器数量更多，包括所有的幼虫和蛹。同样，农村地区的房屋指数和布雷图指数均高于城市地区。不同季节和不同环境下的 Stegomyia 指数无统计学差异。塑料、金属容器和汽车轮胎被确定为最具生产力的栖息地，共产生了超过 90%的埃及伊蚊蛹。水的储存、阳光照射、植被和有机物是埃及伊蚊幼虫丰度的重要预测因子。
在桑给巴尔的农村和城市地区均发现了埃及伊蚊的广泛存在和大量滋生。有关生产性栖息地和水容器滋生预测因子的信息对于开发常规埃及伊蚊监测系统和在桑给巴尔及类似环境中开展有针对性的控制干预措施非常重要。
