The absence of the drhm gene is not a marker for human-pathogenicity in European Anaplasma phagocytophilum strains

Parasites & Vectors

Jasmin Skuballa¹  Martin Ganter²  Joanna Zajkowska³  Tove Hoffman⁴  Friederike D. von Loewenich⁵  Denis B. Langenwalder⁵  Sabine Schmidt⁵  Erik Salaneck⁶  Ioana A. Matei⁷  Andrei D. Mihalca⁷  Urs Gilli⁸  Nikola Pantchev⁹  Cornelia Silaghi^1,10  Miroslav Petrovec^1,11 

[1] Chemical and Veterinary Investigations Office Karlsruhe (CVUA Karlsruhe), Weissenburgerstrasse 3, 76187, Karlsruhe, Germany;Clinic for Swine and Small Ruminants, University of Veterinary Medicine Hannover, Bischofsholer Damm 15, 30173, Hannover, Germany;Department of Infectious Diseases and Neuroinfections, Medical University of Białystok, ul.Żurawia 14, 15-345, Białystok, Poland;Department of Medical Biochemistry and Microbiology (IMBIM), Zoonosis Science Center, Uppsala University, Uppsala, Sweden;Department of Medical Microbiology and Hygiene, Medical Center of the Johannes Gutenberg-University Mainz, Obere Zahlbacherstrasse 67, 55131, Mainz, Germany;Department of Medical Sciences, Zoonosis Science Center, Uppsala University, Uppsala, Sweden;Department of Parasitology and Parasitic Diseases, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Calea Manastur 3-5, 400372, Cluj-Napoca, Romania;IDEXX Diavet AG, Schlyffistrasse 10, 8806, Bäch, Switzerland;IDEXX Laboratories, Mörikestrasse 28/3, 71636, Ludwigsburg, Germany;Institute of Infectology, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald-Insel Riems, Germany;Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Zaloška 4, 1000, Ljubljana, Slovenia;

关键词: Anaplasma phagocytophilum;    ankA;    APH_0919;    APH_0922;    Asia;    drhm;    Europe;    Human;    Multilocus sequence typing (MLST);    North America;    Pathogenicity;   

DOI  :  10.1186/s13071-020-04116-z

来源: Springer

【 摘 要 】

BackgroundAnaplasma phagocytophilum is a Gram-negative obligate intracellular bacterium that replicates in neutrophil granulocytes. It is transmitted by ticks of the Ixodes ricinus complex and causes febrile illness in humans and animals. The geographical distribution of A. phagocytophilum spans the Americas, Europe, Africa and Asia. However, human disease predominantly occurs in North America but is infrequently reported from Europe and Asia. In North American strains, the absence of the drhm gene has been proposed as marker for pathogenicity in humans whereas no information on the presence or absence of the drhm gene was available for A. phagocytophilum strains circulating in Europe. Therefore, we tested 511 European and 21 North American strains for the presence of drhm and compared the results to two other typing methods: multilocus sequence typing (MLST) and ankA-based typing.ResultsAltogether, 99% (478/484) of the analyzable European and 19% (4/21) of the North American samples from different hosts were drhm-positive. Regarding the strains from human granulocytic anaplasmosis cases, 100% (35/35) of European origin were drhm-positive and 100% (14/14) of North American origin were drhm-negative. Human strains from North America and Europe were both part of MLST cluster 1. North American strains from humans belonged to ankA gene clusters 11 and 12 whereas European strains from humans were found in ankA gene cluster 1. However, the North American ankA gene clusters 11 and 12 were highly identical at the nucleotide level to the European cluster 1 with 97.4% and 95.2% of identity, respectively.ConclusionsThe absence of the drhm gene in A. phagocytophilum does not seem to be associated with pathogenicity for humans per se, because all 35 European strains of human origin were drhm-positive. The epidemiological differences between North America and Europe concerning the incidence of human A. phagocytophilum infection are not explained by strain divergence based on MLST and ankA gene-based typing.

【 授权许可】

CC BY