Anaplasma marginale and Anaplasma phagocytophilum are the most important tick-borne bacteria of veterinary and public health significance in the family Anaplasmataceae. The objective of current review is to provide knowledge on ecology and epidemiology of A. phagocytophilum and compare major similarities and differences of A. marginale and A. phagocytophilum. Bovine
anaplasmosis is globally distributed
tick-borne disease of livestock with great economic importance in cattle industry. A. phagocytophilum, a cosmopolitan zoonotic tick transmitted pathogen of wide mammalian hosts. The
infection in domestic animals is generally referred as tick-borne
fever. Concurrent
infections exist in ticks, domestic and wild animals in same geographic area. All age groups are susceptible, but the prevalence increases with age. Movement of susceptible domestic animals from tick free non-endemic regions to disease endemic regions is the major risk factor of bovine
anaplasmosis and tick-borne
fever. Recreational activities or any other high-risk tick exposure habits as well as
blood transfusion are important risk factors of
human granulocytic anaplasmosis. After
infection, individuals remain life-long carriers. Clinical
anaplasmosis is usually diagnosed upon examination of stained blood smears. Generally, detection of serum
antibodies followed by molecular diagnosis is usually recommended. There are problems of sensitivity and cross-reactivity with both the Anaplasma species during serological tests.
Tetracyclines are the drugs of choice for treatment and elimination of
anaplasmosis in animals and humans. Universal
vaccine is not available for either A. marginale or A. phagocytophilum, effective against geographically diverse strains. Major control measures for bovine
anaplasmosis and tick-borne
fever include rearing of tick-resistant breeds, endemic stability, breeding Anaplasma-free herds, identification of regional vectors, domestic/wild reservoirs and control, habitat modification,
biological control,
chemotherapy, and vaccinations (
anaplasmosis and/or tick vaccination). Minimizing the tick exposure activities, identification and control of reservoirs are important control measures for
human granulocytic anaplasmosis.