Background: Francisella tularensis is a Gram-negative bacterium that causes tularemia in both human and animals. Tularemia is a potential serious zoonotic disease that is transmitted by different routes, including tick bites. Materials and Methods: This study deals with investigating the prevalence of F. tularensis in the ticks of local animal farms in Kurdistan region since the farmers are normally in close contact with livestock. We used molecular methods for this purpose. A total of 412 tick and 126 blood samples were gathered from goat, sheep, and cow flocks. The existence of F. tularensis 16Sr RNA gene was examined in the samples using nested-PCR technique. Results: In the animal blood specimens, no F. tularensis was found. The incidence of F. tularensis was 1.7% (7 out of 412) in the tick samples, representing a very lower possibility of tuleremia infection. Moreover, the two subspecies of F. tularensis novicida and holarctica were identified based on the sequencing of pdpD and RD genes, respectively. The F. tularensis subsp. novicida was isolated from four species of ticks, Hyalomma anatolicum, Rhipicephalus annulatus, Rhipicephalus sanguineus, and Ornithodoros spp., whereas the F. tularensis subsp. holarctica was isolated from Haemaphysalis parva and Hyalomma dromedarii species of ticks. Conclusion: Although its prevalence is very low, the isolation of F. tularensis subsp. holarctica from the ticks of farm animals suggests possible transmission of Tularemia through tick bite in Kurdistan region of Iraq. Ref: IR-UU-AEC-3/22.
Keywords: 16Sr RNA; Francisella tularensis; Iraq; livestock; tick.