Resting habitat, blood meal source and viral infection rate of Aedes aegypti (Diptera: Culicidae) in the Southern Afar Region of Ethiopia

BackgroundKnowledge of Aedes species distribution, preference to feed on humans, and susceptibility to viruses is crucial in preventing transmission of Aedes-transmitted viruses. This study aimed to determine resting behavior, blood sources, and viral infection status of Aedes aegypti in Awash Sebat, Awash Arba, and Werer towns of Afar Region.MethodsAdult mosquitoes were collected using a Prokopack aspirator between 8:00-14:00 and 15:00-18:00 h both indoor and outdoor of the house. The mosquitoes were sorted by sex, date of collection, collection places, and abdominal status and identified by species/genus using standard keys. Blood meal sources and dengue virus and chikungunya virus infection status of Ae. aegypti were determined using ELISA and RT-qPCR respectively.ResultA total of 2,745 adult mosquitoes comprising the genera Aedes (1433; 52.2%) Culex (1292; 47.1%) and Anopheles (20; 0.7%) were collected. The proportion of female Ae. aegypti in Awash Sebat (611; 36%) was highest as compared to females Ae. aegypti in Awash Arba (172; 33.8%), and in Werer (59; 11%). A higher proportion of outdoor resting of Ae. aegypti was caught from tyres rather than other indoor and outdoor locations (314; 37.29%) (X2 27.374, df = 12; p = 0.007). Seasonal and monthly variation was observed in Ae. aegypti collection, where the wet season and the months of August 2022, September 2022, and October 2022 had high Ae aegypti density. The overall human blood and bovine blood indices of Ae. aegypti were 53/145 (36.6%) and 18/145 (12.4%), respectively. Furthermore, dengue and chikungunya viruses were not detected from the Ae. aegypti examined.ConclusionThe majority of Ae. aegypti collections were made during the wet season from outdoor resting sites, particularly from tyres. Thus, outdoor targeted management of Ae. aegypti is recommended as a strategy particularly tyre removal during the wet season, to reduce resting and proliferation of Ae. aegypti and hence prevent the risks of Aedes-borne disease transmission.