Detection of brucellosis in dairy cows and humans in Wukro district, Tigray, Ethiopia

Brucellosis, a zoonotic disease, is a world-wide problem of both public health and economic importance. It impacts Ethiopia's economy and affecting both livestock and humans. Varying prevalence exists among different species, with risk factors in livestock including herd size, parity, abortion history, and production systems. A cross-sectional study was conducted to assess brucellosis sero-positivity in five dairy farms, 40 dairy farm workers and 31 patients with pyrexia of unknown origin and to investigate the allied risk-factors. Sera samples of human and dairy cows were screened with Rose Bengal Plate Test and confirmed using Complement Fixation Test (CFT). A structured questionnaire was used to assess potential risk factors among study participants. Descriptive and analytic statistics were employed, including multinomial logistic regression and Chi-square tests, to examine the association between these risk factors and seropositivity to Brucella antibody. Results revealed that i the overall seroprevalence of brucella antibodies in dairy animals was 6.3% with CFT. The seropositivity to brucella antibodies was statistically associated with age of dairy cows (χ2 = 5.1, P = 0.025), parity (χ2 = 11.9, P = 0.018), breed (χ2 = 8.3, P = 0.016) and history of abortion and retained foetal membrane (χ2 = 14.9, P = 0.0001). The seropositivity of brucellosis via CFT in dairy farm workers was 10%. Statistical associations were found between seropositivity and activities such as milking, raw milk/meat consumption, assisting during delivery, and contact with vaginal discharge. Among 31 patients with fever of unknown origin, 16.1% tested positive. To mitigate brucellosis in the study area, focus on vaccinating livestock, enhancing farm hygiene, and educating workers on risks associated with milking, raw milk consumption, and assisting during deliveries is important. Addressing these risk factors can reduce public health and economic impact of the disease.