Detection of Bluetongue Virus Antibodies and Associated Risk Factors Among Camels (Camelus dromedarius): A Cross-Sectional Study

Abstract

Bluetongue (BT) is a non-contagious, vector-borne viral disease transmitted primarily by biting midges of the genus Culicoides. It affects both wild and domestic ruminants, including sheep, goats, cattle, deer, elk, and camels. This study aimed to assess the seroprevalence of bluetongue virus (BTV) antibodies in camels reared in central Sudan and to identify potential risk factors associated with its transmission. A total of 184 blood samples were collected from six localities within Khartoum State using a multi-stage random sampling approach. Data on herd management and farm characteristics were obtained through a semi-structured questionnaire. Serological analysis for BTV antibodies was conducted using a competitive enzyme-linked immunosorbent assay (cELISA). The results revealed a high overall seroprevalence of BTV antibodies in camels (66.8%; 95% CI: 60-73%). Camels acquired from markets or other farms were significantly less likely to be seropositive (OR=0.42; 95% CI: 0.223-1.071; p=0.040) compared to those raised on-site. Additionally, camels reared alone had a significantly lower risk of infection (OR=0.176; 95% CI: 0.043-0.771; p=0.016) than those kept with other animals. These findings indicate that BTV is endemic in the region and that asymptomatic camels may play a role in its transmission. Preventive measures, including vector control, trade restrictions, and vaccination programs, are recommended to reduce the risk of BTV spread among susceptible livestock.