Anaplasma is a genus of rickettsiales bacteria. Anaplasmas reside in host blood cells and lead to the disease anaplasmosis. The disease most commonly occurs in tropical areas of the world. Anaplasmas require intermediate tick hosts (eg. Dermacentor ) for maturation, and flies may act as mechanical vectors. One of the major consequences of infection by red blood cells infecting Anaplasma is the development of haemolytic anaemia due to the damage done to red blood cells. Species of veterinary interest include: