Molecular detection of Coxiella burnetii in ticks collected from different parts of Sistan, south-east of Iran

Background and Objective: Q fever is a worldwide zoonosis caused by Coxiella burnetii (Gammaproteobacteria: Legionellales: Coxiellaceae), the causative agent of Q fever in human and coxiellosis in animals. More than ۴۰ tick species have been reported as carriers of C. burnetii. Transmission of Coxiellaburnetii in the human population is generally air-borne. However, ticks maintain bacterial cycle in nature. The aim of the present study was to examine the potential role of hard ticks found on livestock in transmitting Coxiella burnetii in Sistan region, south-east of Iran.Materials and Methods: ۲۲۰ livestock including ۱۵۰ sheep, ۵۰ goats and ۲۰ cows in five counties of Sistan province (Zabol, Zehak, Hirmand, Nimruz and Hamun) were sampled. Species were diagnosed under stereomicroscope according to valid morphological keys. Ticks were washed with ۷۰% ethanol and air dried for ۱۰ min. DNA was extracted using the QIAamp DNA Mini Kit (Qiagen, Hilden, Germany) according to the manufacturer’s instructions. Polymerase chain reaction (PCR) method was used to detect the Coxiella burnetii genome in ۱۰۰ ticks (based on IS۱۱۱۱ gene which is a transposon-like repetitive region). Negative and positive controls were distilled water and Coxiella burnetii Nine Mile phase I DNA, respectively Findings: In terms of diversity, two genera and three species were identified as follows: ۲۳۹ RhipicephalusSanguineus (۴۰.۱%), ۳ nymphs of Rhipicephalus (۰.۵%), ۲۸۳ Hyalomma Anatolicum (۴۷.۵%), ۹ Hyalomma spp. (۱.۵%) and ۶۲ Hyalomma nymphs (۱۰.۴%). PCR results showed that none of the tested ticks were infected with Coxiella burnetiiConclusion: Although no positive sample was detected, it should not be forgotten that Sistan and Baluchestan province is considered as an endemic foci of Q-fever. As a result, further investigation with larger sample sizes and different molecular methods are required to clarify and confirm our outcome

Keywords:

Q-fever , Coxiella burnetii , PCR , Tick , Sistan