| yellow fever in the gambia, 1978--1979: epidemiologic aspects with observations on the occurrence of orungo virus infections. | an epidemic of yellow fever (yf) occurred in the gambia between may 1978 and january 1979. retrospective case-finding methods and active surveillance led to the identification of 271 clinically suspected cases. a confirmatory or presumptive laboratory diagnosis was established in 94 cases. the earliest serologically documented case occurred in june 1978, at the extreme east of the gambia. small numbers of cases occurred in august and september. the epidemic peaked in october, and cases continued ... | 1980 | 7435793 |