Rift Valley Fever Virus Exposure in Camels and Horses Across Northern Nigeria Livestock Markets.

Rift Valley Fever (RVF) is a neglected vector-borne zoonotic disease of significant veterinary and public health concern in Sub-Saharan Africa. This study investigated the seroprevalence of Rift Valley Fever Virus (RVFV) exposure and associated risk factors among camels and horses marketed in northern Nigeria. A total of 1117 animals were sampled, comprising camels (812) and horses (305), across three major livestock markets (Maigatari, Maiduguri, and Illela). The overall seroprevalence was 18.8% (95% CI: 16.6-21.2%), with a striking six-fold disparity: camels showed a prevalence of 24.4% (95% CI: 21.6-27.4%), while horses exhibited only 3.9% (95% CI: 2.1-7.0%). Significant geographic clustering was observed, with Illela camels recording the highest prevalence (34.8%) compared to those in Maigatari (20.3%) and Maiduguri (20.2%). There were no significant associations with age or sex among camels. However, in horses, females were significantly more likely to test positive than males (OR = 0.27, 95% CI: 0.07-0.97). These findings demonstrate endemic RVFV circulation in Nigerian livestock, highlighting species- and location-specific differences, and underscore the zoonotic risks within regional and transboundary livestock trade networks.