Epidemic o'nyong-nyong fever in southcentral Uganda, 1996-1997: Entomologic studies in Bbaale village, Rakai district

Entomologic studies were conducted between January 27 and February 2, 1997, in Bbaale village in southcentral Uganda during an o'nyong-nyong (ONN) vir us epidemic, which began in mid 1996 and continued into 1997. The objective s were to confirm the role of anophelines in ONN virus transmission and to examine other mosquito species as epidemic vectors of ONN virus. Of 10,050 mosquitoes collected using light traps and pyrethrum knockdown sprays, Anop heles (Cellia) funestus Giles was presumed to be the principal vector becau se it was the most abundant mosquito species from which a strain of ONN vir us was isolated. This virus was isolated for the first time from a culicine species. Mansonia (Mansonioides) uniformis Theobald. Bwamba virus and Nyan do virus were also isolated from An. funestus.