Anaplasma phagocytophilum

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A·na·plas·ma pha·go·cy·to·phil·um

(an'ă-plaz'mă fā'gō-sī-tŏ-f'il-um)
A bacterial species that causes human granulocytic ehrlichiosis; also causes tick-borne fever in cattle; spread by ticks (Ixodes), it occurs in the United States in the Middle Atlantic states, southern New England, and the lower Midwest.

Anaplasma phagocytophilum

(an″ă-plaz′mă fag″ŏ-sī-tof′ĭ-lŭm)
A small gram-negative coccus that is an obligate intracellular parasite. It can be transmitted to humans by tick bite and is the cause of the disease formerly known as human granulocytic ehrlichiosis (now known as anaplasmosis). It was formerly called Ehrlichia phagocytophila.


a genus of organisms in the family Anaplasmataceae, order Rickettsiales. Members parasitize erythrocytes, thrombocytes and leukocytes and are transmitted by ticks.

Anaplasma bovis
causes benign bovine rickettsiosis in Asia and Africa. Previously Ehrlichia bovis.
Anaplasma caudatum
often found in mixed infections with A. marginale in cattle.
Anaplasma centrale
causes a mild form of anaplasmosis in cattle and has been used as a vaccine against A. marginale.
Anaplasma marginale
a significant pathogen, the cause of anaplasmosis in ruminants. The infection is transmitted mechanically by many biting insects. Ticks, including Boophilus spp. and Dermacentor spp., are biological vectors.
Anaplasma ovis
the cause of anaplasmosis of sheep.
Anaplasma phagocytophilum
causes tickborne fever or 'pasture disease' in cattle, goats, sheep and wild ruminants; granulocytic ehrlichiosis in cattle, cats and llamas, both of which are characterized by leukopenia and thrombocytopenia, equine ehrlichiosis, and human granulocytic ehrlichiosis. Transmitted by Ixodes ticks. Previously Ehrlichia equi (Rickettsia phagocytophila and Rickettsia equi), E. phagocytophila and the human granulocytic ehrlichiosis (HGE) agent.
Anaplasma platys
the cause of canine infectious cyclic thrombocytopenia. The only rickettsia known to infect platelets. Thought to be transmitted by Rhipicephalus sanguineus. Previously called Ehrlichia platys.
References in periodicals archive ?
Equine and canine Anaplasma phagocytophilum strains isolated on the island of Sardinia (Italy) are philogenetically related to pathogenic strains from the United States.
first identified coinfections in ixodid ticks with Borrelia burgdorferi and Anaplasma phagocytophilum, the bacterial agent of anaplasmosis (formerly human granulocytic ehrlichiosis).
A serological survey of tick-borne pathogens in dogs in North America and the Caribbean as assessed by Anaplasma phagocytophilum, A.
Anaplasma phagocytophilum is a well recognized agent of granulocytic anaplasmosis, possessing influence on neutrophils and rarely eosinophils (2).
Anaplasma phagocytophilum adult, nymph, and larvae MDLs were determined to be 6,300; 6,900; and 5,400 copies, respectively.
Anaplasma phagocytophilum IFA equine Kit, sufficient for 2000 determinations,
In the study, researchers reported that a protein called OmpA on the surface of Anaplasma phagocytophilum is important for invading host cells.
Insights into pathogen immune evasion mechanisms: Anaplasma phagocytophilum fails to induce an apoptosis differentiation program in human neutrophils.
Researchers in many different countries and climates explore such topics as RNAi and the study of insect immunity, the Picorna-like Kakugo virus identified in aggressive honeybee workers, encephalitic arboviruses as an emerging and re-emerging problem, neurologic manifestations of West Nile Virus infection, the effects of co-infection with Borrelia Burgdorferi and Anaplasma Phagocytophilum in vector ticks and vertebrate hosts, and the cellular secretion of Sf21 cells upon baculovirus infection.
equi and is now referred to as Anaplasma phagocytophilum (which will be used throughout the rest of the discussion).
This publication was also the first and only report claiming human-to-human transmission of Anaplasma phagocytophilum (or, to my knowledge, of any rickettsial agent in the absence of a blood transfusion or a needlestick) and is frequently cited in articles on tickborne infections (2,3).