Identification of Anaplasma phagocytophilum on the basis of a fragment of the 16S rDNA gene.

Anaplasma phagocytophilum is a bacterial parasite of human and animal granulocytes. Instances of granulocytic anaplasmosis (formerely HGE--human granulocytic ehrlichiosis) have been noted in Europe, including northeastern Poland. Here the results of studies on the occurrence of Anaplasma pathogens in ticks Ixodes ricinus in Western Pomerania are presented. 4,6% of the tick population was infected. Sequence analysis of the 16S rDNA gene, necessary for the classification of the bacteria, revealed that the pathogens were A. phagocytophilum, causing disease in people and domestic animals. The DNA sequences were identical to the sequence considered as a prototype for human granulocytic anaplasmosis (U02521, USA). A neighbor-joining tree was constructed using the A. phagocytophilum sequence (AY303572) from Western Pomerania and 10 sequences from the Ehrlichiae and Anaplasmataceae families downloaded from GenBank. The AY303572 sequence clusters with other pathogenic species found in Europe and the U.S.A.