Estimation of Brucella and Mycobacterium bovis contamination in bovine milk in Africa

Abstract

Background and Aim: Bovine brucellosis and tuberculosis are zoonotic bacterial diseases transmitted through the consumption of raw milk and dairy products. Many developed countries have eliminated bovine brucellosis and tuberculosis in their cattle herds, however, the diseases are still endemic in Africa. Despite the public health risk of these pathogens, the sale and consumption of unpasteurized milk are still common in some African countries. This study aimed to estimate the prevalence of Brucella and Mycobacterium bovis in bovine milk. Materials and Methods: A conceptual model for milk contamination was constructed and 1 million simulations were performed using data from published articles. Results: Brucella milk contamination was estimated at a median of 8.68% (interquartile range [IQR]: 5.95-11.97%; range: 2.41-25.16%). The median prevalence of M. bovis was estimated at 6.86% (IQR: 4.25-9.40%; range: 0.01-15.16%). Conclusion: These results indicate that there is a risk of Brucella and M. bovis transmission through the consumption of unpasteurized milk. The findings of this study highlight the need to improve the safety and quality of informally marketed milk in the region.