First molecular survey of Anaplasma phagocytophilum in hard ticks (Ixodidae) from Southwestern Iran.

Anaplasma phagocytophilum is a gram-negative obligate intracellular tick-borne rickettsia with veterinary and public health importance worldwide. This organism is an etiologic agent of tick-borne fever (TBF) in domesticated animals and human granulocytic anaplasmosis (HGA) as well. Hard ticks (Ixodida: Ixodidae) are incriminated as the main biologic vectors for Anaplasma spp. Studies represent that Ixodes spp. are the main vectors for A. phago-cytophilum and few reports hinted that other tick species may play this role. So, the goal of the presented work was to investigate the A. phagocytophilum in 2000 hard ticks in Khuzestan province of Iran by specific nested-PCR performing two consecutive amplifications of 16SrRNA gene fragment with highly variable nucleotide region. Each reaction included 10 salivary glands of distinct tick species. Specific nested-PCR on accumulated salivary glands detected specific bands in 15.5% of reactions (31 of 200) in electrophoresis only in Rhipicephalus sanguineous and Hyalomma marginatum ticks. We concluded that the broad distribution of A. phagocytophilum infection is not only is due to the existence of Ixodes spp. but other hard ticks may also play a role in this issue.