The first serological detection and risk factors analysis of tick-borne Crimean-Congo hemorrhagic fever virus among sheep in Algeria

The Crimean-Congo hemorrhagic fever (CCHF) is one of the zoonotic arboviral diseases transmitted by ticks. It is endemic in several parts of the world, including some African countries. This study was carried out to determine the possible circulation of the CCHF virus in Algeria. To this end, the study was carried out in several regions of northeastern Algeria, in which the sheep species was particularly targeted because of its importance in the epidemiology of the disease. Blood samples were collected from 276 sheep between September and November 2023, and the obtained sera were analyzed using an Enzyme-Linked Immunosorbent Assay (ELISA) to detect the presence of anti-CCHF virus antibodies. Region, age, sex, livestock farming type, and farm management system were analyzed as potential risk factors using a Chi-square (χ2) test and a multivariate regression analysis. The results revealed an overall prevalence rate of 39.13 %, suggesting the exposure of the sheep population to the CCHF virus, and hence the circulation of the virus throughout the study region. Region, age, and livestock farming type were determined to be potential risk factors associated with exposure to the CCHF virus. This is the first study to report the circulation of the CCHF virus among the Algerian sheep population. Further studies should be carried out to better understand CCHF epidemiology in the country.