Evaluation of CCHF Virus Infection in Hard Ticks, Razavi Khorasan Province, Iran

Background: Crimean-Congo hemorrhagic fever (CCHF) is a potentially fatal tick-borne viral disease. Hard ticks are both carriers and reservoirs of the CCHF virus. In this regard, the present study is aimed to investigate the CCHF virus infection in collected ticks from livestock in Gonabad City (southwest of Razavi Khorasan province) in eastern Iran. Methods: This descriptive study was performed in rural areas of Gonabad City in 2018. The forceps sampling method collected hard ticks from livestock (goats, sheep, and cattle). The ticks were identified based on a valid taxonomic key; finally, the CCHF virus infection was evaluated using RT-PCR the technique. Results: Between April and October 2018, 100 ticks were collected from 13 rural areas of Gonabad. The frequency of ticks collected from goats, sheep, and cows were 6.4%, 3.7%, and 89.9%, respectively. 90% of ticks were Hyalomma (Hyalomma anatolicum excavatum (n=9), Hyalomma lusitanicum (n=59), Hyalomma marginatum (n=4), Hyalomma anatolicuman (n=18)) and the remaining 10% were Rhipicephalus sanguine.  Overally, CCHF infection was observed in 14% of the ticks (Hy. excavatum, Hy. lusitanicum, Hy. anatolicumand Rhipicephalus sanguineus). Conclusion: Hyalomma species is the main vector of the CCHF virus. Due to the abundance of hard ticks in nature and the livestock environment, special required in the villages with a high abundance of such hard ticks. Also, regarding higher scattered ticks in the northern country’s northern half comprehensive studies covering a wide geographical area and a larger sample size are necessary.