Serologic Survey of Crimean-Congo Haemorrhagic Fever among Sheep in Ardabil Province, Northwest Iran

Livestock is a known source of Crimean-Congo Hemorrhagic Fever (CCHF) virus infection in humans. Although CCHF is endemic in Iran, limited human cases of CCHF are reported from northwest of Iran. Considering the lack of complete and updated information on the status and distribution of CCHF infection among domestic animals in Ardabil province, this study was conducted to investigate the CCHF status among sheep in this area.
In this study, 256 sera from sheep were collected from various geographical regions of Ardabil in 2011, and tested for specific CCHF IgG antibodies by ELISA.
The Seroprevalence of CCHF in this area was 27.34%. The seropositivity rate of CCHF in northern regions (36.36%) was higher than in central (26.27%) and southern (20%) regions. The highest and lowest seropositivity of CCHF were seen in Parsabad (45.57%) and Khalkhal counties (17.78%), respectively.
In this study, a relatively high seroprevalence of CCHF was seen among livestock in the province. Therefore, health care system should increase its surveillance for the detection of CCHF patients. Molecular studies to compare the virus strains circulating in this province and those in the eastern regions of the country can shed more light on the epidemiology of the disease.