<i>Coxiella burnetii</i> in dogs and ticks from the Northeastern Anatolia region of Türkiye: serological and molecular findings.

The Q fever is a zoonotic bacterial infection caused by an obligate intra-cellular bacterium, <i>Coxiella burnetii</i>. Members of the Canidae family (Mammalia), including dogs and foxes, are potential reservoirs of <i>C. burnetii</i>, which has a wide host range from mammals and birds to arthropods (primarily ticks). Infected dogs can transmit the disease to other animals and humans. This study aimed to investigate the presence of <i>C. burnetii</i> in dogs and ticks collected from infested dogs in the Kars, Ardahan, and Iğdir provinces of Türkiye by serological and molecular methods. Three hundred canine serum samples were analyzed for phase I and phase II <i>C. burnetii</i> antibodies using indirect enzyme-linked immunosorbent assay. Whole blood samples (n = 300) from the dogs sampled for sera and 184 ticks randomly collected from these dogs were also analyzed for <i>C. burnetii</i> with touch-down polymerase chain reaction. The ticks were classified according to the taxonomic characteristics. In result, 107 tick DNA samples collected from individual females and pooled males were evaluated. The <i>C. burnetii</i> was detected in 3.73% (of the tick samples. However, <i>C. burnetii</i> was not detected in any of the canine blood samples by polymerase chain reaction. Out of the 300 dogs, 18.33% presented antibodies against <i>C. burnetii</i> in their blood serum. When assessed for location, <i>C. burnetii</i> seropositivity was found to be significantly high especially in the Northeastern Anatolia region (18.33%). Study data highlighted the zoonotic risk of ticks, demonstrating that ticks on dogs can carry <i>C. burnetii</i>.