Ebola virus infection in man: a serological and epidemiological survey in the Cameroons

The presence of antibodies to Ebola virus among 1,517 apparently healthy persons in five regions of the Cameroons was tested using indirect immunofluorescence. A positive rate of 9.7% was found, confirming that the virus circulates in the absence of clinical cases. Highest rates were found among Pygmies, young adults, and rain forest farmers.