The role of different species of wild ungulates and Ixodes ricinus ticks in the circulation of genetic variants of Anaplasma phagocytophilum in a forest biotope in north-western Poland

The aim of this study was to reveal genetic variants of Anaplasma phagocytophilum strains occurring in different species of wild ungulates and in Ixodes ricinus ticks to check the role of the examined species in the circulation of the revealed variants in nature. The aim was also to determine if the detected variants of A. phagocytophilum are specific for particular game species as well as to examine their identity with other strains, including pathogenic ones. Sequences of the amplified groEL heat shock operon and msp2 gene fragments of A. phagocytophilum were obtained from samples collected between 2005 and 2007 from 14 roe deer (Capreolus capreolus), 13 red deer (Cervus elaphus), 1 fallow deer (Dama dama) and 4 wild boar (Sus scrofa) as well as 13 engorged and 11 questing I. ricinus ticks occurring in the area of Puszcza Wkrzańska Forest in north-western Poland. Analysis of the sequences showed the presence of five and four gene variants of groEL and msp2, respectively. The variants showed high identity with sequences derived from strains pathogenic to humans and/or domestic and companion animals. Cervids seem to play a more important role in the circulation of the detected variants in nature than wild boar. Some of the detected variants are not shared by roe and red deer. The results obtained on the basis of groEL and msp2 sequences are discrepant. Analysis of the groEL operon sequence provides more information on A. phagocytophilum strains than the msp2 gene sequence.