Dromedaries are an important livestock, used as beasts of burden and for meat and milk production. However, they can act as an intermediate source or vector for transmitting zoonotic viruses to humans, such as the Middle East respiratory syndrome coronavirus (MERS-CoV) or Crimean-Congo hemorrhagic fever virus (CCHFV). After several outbreaks of CCHFV in the Arabian Peninsula, recent studies have demonstrated that CCHFV is endemic in dromedaries and camel ticks in the United Arab Emirates (UAE). There is no apparent disease in dromedaries after the bite of infected ticks; in contrast, fever, myalgia, lymphadenopathy, and petechial hemorrhaging are common symptoms in humans, with a case fatality ratio of up to 40%. We used the in-solution hybridization capture of 100 annotated immune genes to genotype 121 dromedaries from the UAE tested for seropositivity to CCHFV. Through univariate linear regression analysis, we identified two candidate genes belonging to the innate immune system: FCAR and CLEC2B. These genes have important functions in the host defense against viral infections and in stimulating natural killer cells, respectively. This study opens doors for future research into immune defense mechanisms in an enzootic host against an important zoonotic disease.

Al Ain City Municipality Al Ain 505055 United Arab Emirates

Center for Virology Medical University of Vienna 1090 Vienna Austria

College of Medicine Mohammed Bin Rashid University of Medicine and Health Sciences Dubai 505055 United Arab Emirates

Department of Animal Genetics University of Veterinary Sciences Brno 61242 Brno Czech Republic

Division of Infectious Diseases and Tropical Medicine Department of Medicine 1 Medical University of Vienna 1090 Vienna Austria

Research Institute of Wildlife Ecology Department of Interdisciplinary Life Sciences University of Veterinary Medicine Vienna 1160 Vienna Austria

RG Animal Immunogenomics CEITEC VETUNI Brno 61242 Brno Czech Republic

Viral Zoonoses Emerging and Vector Borne Infections Group Institute of Virology University of Veterinary Medicine Vienna 1210 Vienna Austria

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