Cornelia Hildegard Anita Silaghi Prevalence and Genetic Analysis of Anaplasma Phagocytophilum and Spotted Fever Group Rickettsiae in the Tick Ixodes Ricinus in Urban and Periurban Sites in Southern Germany

Anaplasma phagocytophilum DNA was detected by real-time PCR, which targeted the msp2 gene, in 2.9% of questing Ixodes ricinus ticks (adults and nymphs; n = 2,862), collected systematically from selected locations in Bavaria, Germany, in 2006. Prevalence was significantly higher in urban public parks in Munich than in natural forests. Anaplasma phagocytophilum, an obligate intracellular bacterium, causes a febrile disease in ruminants and granulocytic anaplasmosis in dogs, horses, and humans (1). A reorganization of the order Anaplasmataceae reclassified Ehrlichia equi, E. phagocytophila, and the human granulocytic ehrlichiosis (HGE) agent to the single species A. phagocytophilum (2), which in Europe is transmitted by the sheep tick, Ixodes ricinus (3). The agent is found among the I. ricinus population in Germany; average prevalence rates are 1% to 4.5% (4,5). The English Garden, a large (3.7km2) public park in Munich (state of Bavaria, Germany), has been suggested in 2 previous studies as a focal point for A. phagocytophilum (5,6). We investigated A. phagocytophilum in questing ticks in urban areas of Munich and focused on seasonal and geographic effects on the prevalence.