Seid Mohammed, Aklilu Esayas, Animut Abebe
Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.
Department of Biology, College of Natural and Computational Sciences, Mattu University, Mattu, Ethiopia.
Trop Med Health. 2024 Aug 2;52(1):51. doi: 10.1186/s41182-024-00612-5.
Describing spatio-temporal occurrence and habitat characteristics of Aedes mosquito larvae is crucial for the control of Aedes borne viral diseases. This study assessed spatio-temporal abundance and habitat characteristics of Aedes larvae in the Southern Afar Region, Ethiopia.
Immature mosquitoes were surveyed in Awash Sebat, Awash Arba, and Werer towns of the Southern Afar Region once per month from May 2022 to April 2023. Larvae and pupae surveys were carried out along the available water-holding containers. The collected larvae/pupae were reared to adults and identified by species/genus morphologically. The physical and chemical properties of the habitats were also characterized.
A total of 9099 Aedes larvae/pupae were collected, of which 53.6% (4875) were from Awash Sebat, 29.5% (2687) from Awash Arba and 16.9% (1537) from Werer. Water-holding tyres harboured the highest number of Aedes larvae/pupae followed by water-storage drums. All the Aedes larvae/pupae reared to adults were morphologically identified as Aedes aegypti. The overall Container Index was 47.28%, House Index 18.19%, Breteau Index 59.94% and Pupal Index 171.94. Significant positive relations were observed in the occurrences of Ae. aegypti larvae/pupae with water-holding tyre (AOR = 15.89, CI = 3.55-71.09, p < 0.001), water storage drums (AOR = 19.84, CI = 4.64-84.89, p < 0.001), domestic habitat (AOR = 3.76, CI = 1.27-11.12, p = 0.017), and significant negative relations were observed with Ae. aegypti larvae/pupae occurrence and tap water source (AOR = 0.08, CI = 0.02-0.31, p = 0.001). Ae. aegypti larvae/pupae densities showed positive relations with dissolved oxygen (β = 0.523, p < 0.001) and total hardness (β = 0.475, p = 0.034) of water.
Diverse types of artificial water-holding containers were positive for Ae. aegypti larvae/pupae. Ae. aegypti larvae/pupae were abundant in used water-holding tyres, water storage drums, and cement tanks in Awash Sebat, Awash Arba, and Werer towns. This could put the residents of the towns at high risk of infections with Ae. aegypti transmitted viral diseases such as chikungunya and dengue outbreaks. Thus, we recommend artificial water-holding container management as a strategy to control Ae. aegypti and hence the arboviral diseases transmission.
描述埃及伊蚊幼虫的时空分布及栖息地特征对于控制由埃及伊蚊传播的病毒性疾病至关重要。本研究评估了埃塞俄比亚阿法尔南部地区埃及伊蚊幼虫的时空丰度及栖息地特征。
于2022年5月至2023年4月期间，每月对阿法尔南部地区的阿瓦什·塞巴特、阿瓦什·阿尔巴和韦雷尔镇的未成熟蚊子进行一次调查。沿着现有的蓄水容器开展幼虫和蛹的调查。将收集到的幼虫/蛹饲养至成虫，并通过形态学鉴定其种类/属。同时对栖息地的物理和化学性质进行了表征。
共收集到9099只埃及伊蚊幼虫/蛹，其中53.6%（4875只）来自阿瓦什·塞巴特，29.5%（2687只）来自阿瓦什·阿尔巴，16.9%（1537只）来自韦雷尔。蓄水轮胎中埃及伊蚊幼虫/蛹的数量最多，其次是储水桶。所有饲养至成虫的埃及伊蚊幼虫/蛹经形态学鉴定均为埃及伊蚊。总体容器指数为47.28%，房屋指数为18.19%，布雷托指数为59.94%，蛹指数为171.94。观察到埃及伊蚊幼虫/蛹的出现与蓄水轮胎（优势比=15.89，置信区间=3.55 - 71.09，p<0.001）、储水桶（优势比=19.84，置信区间=4.64 - 84.89，p<0.001）、家庭栖息地（优势比=3.76，置信区间=1.27 - 11.12，p = 0.017）呈显著正相关，与埃及伊蚊幼虫/蛹的出现和自来水水源呈显著负相关（优势比=0.08，置信区间=0.02 - 0.31，p = 0.001）。埃及伊蚊幼虫/蛹密度与水中溶解氧（β=0.523，p<0.001）和总硬度（β=0.475，p = 0.034）呈正相关。
多种类型的人工蓄水容器是埃及伊蚊幼虫/蛹的滋生场所。在阿瓦什·塞巴特、阿瓦什·阿尔巴和韦雷尔镇，使用过 的蓄水轮胎、储水桶和水泥罐中埃及伊蚊幼虫/蛹数量较多。这可能使这些城镇的居民面临感染由埃及伊蚊传播的病毒性疾病（如基孔肯雅热和登革热暴发）的高风险。因此，我们建议将人工蓄水容器管理作为控制埃及伊蚊及虫媒病毒疾病传播的一项策略。
