Venereal syphilis in tropical Africa.

A steady decline in the incidence of positive results to the Kahn test is reported in Malawian patients during the period 1968-75. Other studies have shown that the incidence of early and late syphilis in sub-Saharan Africa has dropped considerably over the past few decades. The number of reported cases of early syphilis in certain urban areas, however, appears to be high. It is suggested that the downward trend in the incidence of syphilis in Africa is related to the increased and often indiscriminate use of penicillin.