The historical question of acquired immunodeficiency syndrome in the 1960s in the Congo River basin area in relation to cryptococcal meningitis.

In Europe before the advent of the acquired immunodeficiency syndrome (AIDS), fatal cases of infection with Cryptococcus neoformans resembling acute meningitis were rarely described and never in young adults. However, rapidly fatal cryptococcal meningitis in young Africans has been known to exist in central Africa for at least 30 years, mainly in the lower area of the Congo River basin. Cases have been reported in this area since 1953, particularly in young patients during the 1950s. It is also known that central African AIDS patients frequently suffer from cryptococcosis, and there is a possibility that earlier clinical reports of encephalitis were actually fatal cases of AIDS in young Africans. It appears possible that the central part of the African continent is the area where human immunodeficiency virus originated.