EPIDEMIOLOGY OF BRUCELLOSIS IN PASTORALIST VS. SEDENTARY COMMUNITIES.

Abstract

Brucellosis is a neglected zoonotic disease affecting both humans and livestock, particularly in regions where animal husbandry is central to livelihoods. This study compared the prevalence of brucellosis and associated human–livestock risk factors in pastoralist and sedentary communities in northern Nigeria. A cross-sectional, community-based design was employed, integrating serological surveys in humans and livestock with behavioral risk assessments. A total of 540 adults (270 pastoralist; 270 sedentary) and 300 livestock (150 per community type) were sampled. Human and livestock sera were screened using the Rose Bengal Test and confirmed by indirect ELISA. Human seroprevalence was 24.1% among pastoralists and 10.4% among sedentary participants, while livestock seroprevalence was 40.7% and 18%, respectively. Cattle exhibited the highest infection rates, followed by goats and sheep. Logistic regression identified direct livestock contact, consumption of raw milk, handling of aborted materials, and assisting with animal births as significant human risk factors. Herd-level factors, including history of abortion and larger herd size, were associated with livestock seropositivity. Behavioral observations corroborated higher exposure among pastoralists. The study demonstrates a strong human–livestock epidemiological interface, emphasizing the need for a One Health approach. Findings underscore the importance of targeted community education, livestock vaccination, integrated surveillance, and cross-sectoral policy interventions to reduce brucellosis transmission. This research fills a critical knowledge gap in community-based zoonotic epidemiology and provides evidence to inform culturally appropriate, sustainable disease prevention strategies in both pastoralist and sedentary populations.