A recent chikungunya outbreak associated with the occurrence of Aedes vectors (Diptera: Culicidae) in Kassala state, eastern Sudan in 2018

Aedes aegypti and Ae. albopictus (Diptera: Culicidae) are primary vectors of human arboviral diseases such as dengue, chikungunya, yellow fever, and Zika viruses. Aedes aegypti is well distributed in Sudan, except in Northern and Khartoum states, while Ae. albopictus has not been previously reported. Recently, Eastern Sudan witnessed an unprecedented large outbreak of chikungunya fever between 31 May 2018 and 30 March 2019. The outbreak was composed of four waves; one of them was in Kassala state. Aedes survey in localities of Kassala state (rather than Kassala city) is carried out to assess the possible expansion of the disease in the state. The results showed the presence of immature stages of Aedes spp. in four localities from ten localities. From the four localities that recorded Aedes spp., two localities (Rural Kassala and West Kassala) were reported with chikungunya cases. From this investigation, Ae. albopictus was reported for the first time in Sudan. Also, this investigation showed the importance of conducting entomological surveys with epidemiological surveys during outbreaks of arboviral diseases.