Diversity and Distribution of Hyalomma Ticks and Tick-Borne Pathogens in Dromedary Camels in Chad

Ticks of the genus Hyalomma are major ectoparasites of dromedary camels and serve as important vectors for diverse tick-borne pathogens (TBPs) affecting both animals and humans. In this study, we determined the tick species diversity and distribution and estimated the prevalence of TBPs in those ticks. A total of 780 ticks collected from camels in Bol, Chad, were identified into four species: Hyalomma dromedarii (49.0%), H. rufipes (22.6%), H. impeltatum (19.1%), and H. truncatum (9.4%). Sixty ticks were selected proportionally across the four Hyalomma species and screened for TBPs using PCR. Coxiella burnetii was detected in 11.7% of the ticks, and Rickettsia aeschlimannii in 1.7%. Anaplasmataceae-specific 16S rRNA primers detected Candidatus Midichloria mitochondrii, a tick endosymbiont, in 10% of the ticks. No protozoan pathogens (Theileria or Babesia) were detected. This study highlights the need for integrated surveillance of ticks and their associated microorganisms in Chadian camels to mitigate zoonotic and veterinary risks. Strengthening such efforts will support camel health and pastoral livelihoods in the region.