PREVALENCE OF ANTIBODIES TO COXIELLA-BURNETII, RICKETTSIA-CONORII, AND RICKETTSIA-TYPHI IN 7 AFRICAN COUNTRIES

The prevalences of antibodies reactive with Coxiella burnetii, Rickett sia conorii, and Rickettsia typhi were determined by indirect fluoresc ent antibody testing of sera from seven African countries. The seropre valences of antibodies reactive with C. burnetii and R. conorii in cou ntries from North Africa were similar to those reported from southern Europe. In countries of sub-Saharan Africa, the seroprevalence of anti bodies reactive with C. burnetii varied greatly; the generally higher figures for West Africa, where stock breeding is prominent, suggested that domestic animals might be the main reservoirs of infection. The p revalence of antibodies to the recently described species Rickettsia a fricae was higher than that reported for spotted fever-group rickettsi ae from elsewhere in the world and paralleled the distribution of Ambl yomma species. Western blot results suggested that the antibodies dete cted were more likely to be reactive with R. africae than with R. cono rii, the main vector of which (Rhipicephalus species) rarely feeds on humans. The seroprevalences of antibodies reactive with R. typhi were higher in coastal regions, where Rattus norvegicus-the natural host of the vector Xenopsylla-is more prevalent, than in inland areas.