Ehrlichiosis and Anaplasmosis: Zoonotic Species

Ehrlichiosis and anaplasmosis are tick-borne diseases caused by obligate intracellular bacteria in the genera Ehrlichia and Anaplasma. These organisms are widespread in nature; the reservoir hosts include numerous wild animals, as well as some domesticated species. For many years, Ehrlichia and Anaplasma species have been known to cause illness in pets and livestock. The consequences of exposure vary from asymptomatic infections to severe, potentially fatal illness. Some organisms have also been recognized as human pathogens since the 1980s and 1990s