TICKS PARASITIZING THE SPUR-THIGHED TORTOISE (TESTUDO GRAECA) POPULATION OF TUNISIA

From March to April 2017, a total of 147 free-ranging spur-thighed tortoises (Testudo graeca) was captured in different habitat types of northern Tunisia and examined for tick infestation. A total of 134 was infested, yielding an infestation prevalence of 91.2%. From these tortoises, 1,174 ticks were collected, a subsample (10%, n=120) of which was randomly selected and identified; the remaining ticks were stored at -80 C and examined for zoonotic pathogens. Only adult Hyalomma aegyptium were found among the subsample of ticks collected for spur-thighed tortoise. The prevalence of tick infestation did not vary significantly within the study area but differences in intensity were observed in relation to the size of tortoises and the vegetation coverage. Our results provide strong evidence that adult H. aegyptium is the predominant tick species found on wild spur-thighed tortoises in northern Tunisia, where the species is commonly traded illegally across the Mediterranean Basin. Considering the potential transmission of several zoonotic pathogens by H. aegyptium to humans, we highlight the need to develop a surveillance system to prevent the introduction and the spread of tick-borne pathogens in the Mediterranean Basin.