HTLV-III Antibody in East Africa

To the Editor: In their article about AIDS virus infection in Nairobi prostitutes, (Feb. 13 issue), 1 Kreiss et al. concluded that their data support the hypothesis of transcontinental spread of AIDS from central Africa to Kenya. We believe that the data do not justify this conclusion. Kreiss et al. reported an odds ratio as the estimator of the relative risk of having HTLV-III/LAV antibody in association with sexual exposure to men from various African countries and from North America and Europe. The odds ratio is a good estimator of relative risk only when the disease is rare in the population . . . No extract is available for articles shorter than 400 words.