Anaplasmosis is an infectious, non-contagious, tick-borne hemoparasitic disease of domesticated and wild ruminants living in tropical and subtropical areas worldwide. Bovine anaplasmosis is caused by Anaplasma marginale, sometimes A. centrale and A. caudatum rickettsia. Anaplasmosis was first described in 1910 in South Africa. It is now found worldwide and is endemic in Africa, South and Central America, southern Europe, the Far and Middle East, India, Russia, and Australia.

The form of the disease including its duration and severity of signs depends on the age and the previous exposure to infection.

Transmission
Anaplasma spp are transmitted to cattle mechanically or biologically through arthropod vectors, most commonly ticks but also bloodsucking flies. Once infected, even cattle that recover from the disease will remain carriers of A. marginale for many years, and serve as sources of infection to other cattle.

Incubation period
The incubation period ranges between 2 to 5 weeks.