Rickettsioses have been reported all over Africa. Serologic investigations have been driven using non specific methods as Giroud microagglutination and Weil-Felix test which led to numerous false positive. This explains the difficulties encountered in the evaluation of the prevalence of such diseases in Africa. However, three recent studies made in Tunisia, Central Africa and Zimbabwe show that seroprevalence of spotted fever group rickettsiae infections is close to 45% using MIF as reference method. New technics as Western and Line immunoblotting and RFLP PCR should allowed to new studies and revision of epidemiologic data on rickettsioses in Africa.