SEROLOGIC EVIDENCE FOR HUMAN EHRLICHIOSIS IN AFRICA

Human ehrlichiosis is a recently recognized rickettsial disease. It is caused by Ehrlichia chaffeensis, an intraleucocytic Gram-negative, ob ligate intracellular bacterium, grouped within the genus Ehrlichiae. M ost human cases of ehrlichiosis have been diagnosed in the USA. Two ca ses have been reported outside of the USA, one in Europe and one in Af rica. From 1 January to 30 June 1992, 765 sera from blood donors or ot her asymptomatic subjects in 8 African countries, including Ivory Coas t, Burkina Faso, Mall, Central African Republic, Angola, Zimbabwe, Moz ambique and Commores Islands, were tested by indirect immunofluorescen ce for the presence of E. chaffeensis antibodies. Positive sera were c onfirmed by Western immunoblotting. Only two of 765 sera tested were p ositive. One serum obtained from Burkina Faso had an IgG titer of 1:20 0 and one from Mozambique had an IgG titer of 1:80. Human ehrlichiosis seems to occur infrequently in Africa, although many more sera from a dditional African countries need to be evaluated.