Brucella Seroprevalence and Associated Risk Factors in Occupationally Exposed Humans in Selected Districts of Southern Province, Zambia

Background: Brucellosis is a neglected debilitating zoonosis widely recognized as an occupational health hazard. The seroprevalence of human anti-Brucella antibodies in high-risk populations, as well as their risk factors, have not been well-documented in Zambia. This study aimed at estimating the Brucella seroprevalence in herdsmen and abattoir workers and assess the associated risk factors. Methods: A cross-sectional seroepidemiological study was carried out between May and December 2020 among abattoir workers and herdsmen in Namwala, Monze and Choma districts of Southern Province in Zambia. Seroprevalence was assessed by indirect enzyme-linked immunosorbent assay (i-ELISA) or competitive enzyme-linked immunosorbent assay (c-ELISA) while a questionnaire was administered to obtain epidemiological data. Results: A total of 153 individuals were recruited in the study. The overall Brucella seroprevalence was 20.3% (95% CI: 14.6–27.5). Seropositivity among herdsmen and abattoir workers was 14.4% (95% CI: 9.2–21.8) and 46.4%, (95% CI: 28.8–65.0), respectively. Comparable seropositive results among districts showed Namwala with 26.9%, which was the highest, seconded by Monze 19.0%, and the least was Choma with 11.36%, seropositivity. The multivariate logistic regression model showed that occupation, age category, and district of residence were predictors of being seropositive to Brucella spp. antibodies. The odds of abattoir workers being seropositive to Brucella antibodies were 8.6 (95% CI: 2.6–28.2) higher than that of herdsmen being the reference group. The odds of age category 17–50 years being seropositive to Brucella antibodies were 7.0 (95% CI: 0.7–72.2) higher than being