Moundai Tchonfienet, Hamit Mahamat Alio, Demba Kodindo Israël, Yangalbe Élise Kalnoné, Kerah Hinzoumbé Clément, Abdelsalam Tidjani, Kekeunou Sévilor
Programme national de lutte contre le paludisme, ministère de la Santé publique, Tchad.
Laboratoire des recherches, diagnostics et d'expertises scientifiques, Université de N'Djamena, Tchad.
Med Trop Sante Int. 2024 Dec 19;4(4). doi: 10.48327/mtsi.v4i4.2024.619. eCollection 2024 Dec 31.
The aim of this study was to identify chikungunya vectors and study their bioecology in order to contribute to the response to the 2020 epidemic in the cities of Abéché and Biltine in eastern Chad.
Immature stages of mosquitoes were collected and epidemic risk indices (Container index, House index and Breteau index) were calculated and compared using the Chi-square test. The collected larvae and nymphs were reared, and the resulting adults were morphologically identified using a dichotomous key. Residual endophilic fauna was sampled by morning insecticide spraying in chambers. Only female mosquitoes were collected.
A total of 2,039 mosquito specimens belonging to three genera were collected: 470 (23%) were identified as 731 spp (36%), and 838 Culex spp (41%). Flowerpots were the most common breeding sites (69%), followed by jars/water barrels (17%) abandoned tires or containers (14%). The risk indices were all well above the epidemic thresholds defined by the WHO. Between the two cities, only the house index showed a significant difference (p=0.004): it was higher in Abéché than in Biltine.
The study identified as a likely vector of chikungunya in both cities. It is important to understand its biting and resting behavior, as well as its sensitivity to different classes of insecticides, in order to organize effective vector control.
本研究旨在确定基孔肯雅热的病媒并研究其生物生态学，以便为应对2020年乍得东部阿贝歇和比尔廷两市的疫情做出贡献。
收集蚊虫的幼虫阶段，计算疫情风险指数（容器指数、房屋指数和布雷图指数），并使用卡方检验进行比较。对收集到的幼虫和若虫进行饲养，然后使用二分检索表对羽化出的成虫进行形态学鉴定。通过早晨在室内喷洒杀虫剂对残余嗜室内动物群进行采样。只收集雌蚊。
共收集到属于三个属的2039只蚊虫标本：470只（23%）被鉴定为伊蚊属，731只（36%）为按蚊属，838只（41%）为库蚊属。花盆是最常见的孳生地（69%），其次是罐子/水桶（17%）、废弃轮胎或容器（14%）。风险指数均远高于世界卫生组织定义的疫情阈值。在这两个城市之间，只有房屋指数显示出显著差异（p=0.004）：阿贝歇的房屋指数高于比尔廷。
该研究确定伊蚊属在这两个城市均可能是基孔肯雅热的病媒。了解其叮咬和栖息行为以及对不同种类杀虫剂的敏感性，对于组织有效的病媒控制很重要。
