Histoplasmosis in Africa: a review.

Classical histoplasmosis caused by Histoplasma capsulatum var. capsulatum, and African histoplasmosis caused by H. capsulatum var. duboisii are both endemic in Africa. In South Africa, only classical histoplasmosis caused by Histoplasma capsulatum var. capsulatum is known to occur and cases are seen frequently. It occurs sporadically in several other African countries. Histoplasma capsulatum var. capsulatum is known to occur naturally in caves inhabited by bats in some parts of South Africa, namely, Transvaal and Cape province, Zimbabwe and Tanzania. Outbreaks of histoplasmosis have been reported in cave explorers. Surveys of histoplasmin skin sensitivity carried out in Africa have shown the rate of positive reactors to be from 0.0% to 28%. African histoplasmosis caused by H. capsulatum var. duboisii is prevalent in Western and Central Africa, and in the island of Madagascar between the Kalahari and Sahara deserts, that is between latitudes 20 degrees North and 20 degrees South of the Equator. A natural reservoir of this fungus in soil admixed with bat guano has been found in a bat cave in a rural area, viz. Ogbunike in Anambra State of Nigeria. The clinical features and epidemiology of the two forms of the disease in Africa are reviewed.