Rickettsial diseases in Eastern Africa

Rickettsial diseases have been described in Eastern Africa for over 50 years. These include: epidemic typhus (Rickettsia prowazekii), murine typhus, (Rickettsia typhi) and Mediterranean spotted fever also known as Kenyan tick typhus (Rickettsia conorii subsp. conorii). Contemporary reports describe these same diseases in addition to new rickettsiae and rickettsial diseases utilizing serological and molecular techniques. Some of the new agents and diseases include: Rickettsia felis (flea-borne spotted fever), Rickettsia felis-like organisms (e.g. Candidatus Rickettsia asemboensis), Rickettsia africae (African tick-bite fever), Rickettsia africae variants (e.g. Rickettsia sp. AVR4), Rickettsia aeschlimanni (an unnamed tick-borne rickettsiosis), Rickettsia sibirica subsp. mongolitimonae (lymphangitis-associated rickettsiosis), Rickettsia conorii subsp. israelensis (Israeli spotted fever) and Candidatus Rickettsia kulagini. These reports indicate that individuals residing in and those visiting Eastern Africa are at risk of various rickettsial diseases. Unfortunately, the dearth of comprehensive studies of the prevalence and distribution of these rickettsiae or the incidence of the particular rickettsioses hinder development of proper mitigation strategies.