REVIEW ARTICLE published: 22 July 2013 CELLULAR AND INFECTION MICROBIOLOGY doi: 10.3389/fcimb.2013.00031 Anaplasma phagocytophilum—a widespread multi-host pathogen with highly adaptive strategies Snorre Stuen 1*, Erik G. Granquist 2 and Cornelia Silaghi 3 1 Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, Sandnes, Norway 2 Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo, Norway 3 Department of Veterinärwissenschaftliches, Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität München, Munich, Germany Edited by: The bacterium Anaplasma phagocytophilum has for decades been known to cause Agustín Estrada-Peña, University of the disease tick-borne fever (TBF) in domestic ruminants in Ixodes ricinus-infested Zaragoza, Spain areas in northern Europe. In recent years, the bacterium has been found associated Reviewed by: with Ixodes-tick species more or less worldwide on the northern hemisphere. Lee-Ann H. Allen, University of Iowa, USA A. phagocytophilum has a broad host range and may cause severe disease in several Jason A. Carlyon, Virginia mammalian species, including humans. However, the clinical symptoms vary from Commonwealth University School of subclinical to fatal conditions, and considerable underreporting of clinical incidents is Medicine, USA suspected in both human and veterinary medicine. Several variants of A. phagocytophilum *Correspondence: have been genetically characterized. Identification and stratification into phylogenetic Snorre Stuen, Department of Production Animal Clinical Sciences, subfamilies has been based on cell culturing, experimental infections, PCR, and Norwegian School of Veterinary sequencing techniques. However, few genome sequences have been completed so Science, Kyrkjeveien 332/334, far, thus observations on biological, ecological, and pathological differences between N-4325 Sandnes, Norway genotypes of the bacterium, have yet to be elucidated by molecular and experimental e-mail:
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