Prevalence and Risk Factors of Tuberculosis Lesions in Cattle Slaughtered for Human Consumption at the Slaughterhouses in the City of Ngaoundéré, Cameroon.

INTRODUCTION

Bovine tuberculosis (bTB) is a zoonotic disease of major public health concern, particularly in developing countries such as Cameroon, where control measures are poorly implemented and there is a high risk of human infection. This study aimed to estimate the prevalence of bTB lesions in slaughtered cattle and identify the associated risk factors in slaughterhouses in the city of Ngaoundéré.

METHODOLOGY: A cross-sectional study was conducted to investigate the prevalence of tuberculosis lesions in two slaughterhouses between April and October 2024. Tuberculosis lesions were identified during postmortem inspections performed by veterinary inspectors on slaughtered animals, and the presence of acid-fast bacilli (AFB) in these lesions was detected using Ziehl-Neelsen (ZN) staining. In addition, a structured questionnaire was administered to assess potential risk factors, and their associations with the prevalence of tuberculosis were analyzed using univariate and multivariate logistic regression models.

RESULTS

Among the 1,256 cattle examined, the overall prevalence of bTB was 5.1% (95% CI: 3.88-6.22). Suspicious lesions were detected in 64 carcasses, of which 17.14% were positive for AFB, suggestive of Mycobacterium spp. Regarding the multivariable analysis, only cattle origin remained significantly associated with the outcome, particularly for animals from Touboro (OR = 18.9; 95% CI: 3.3-367.1) and Mbaiboum (OR = 14.9; 95% CI: 2.5-292.2). During the study period, financial losses were estimated based on 302.5 kg of organs condemned due to tuberculosis infection, using prevailing market prices. The total losses were estimated at 541,200 CFA francs. The organs contributing to the highest financial losses were the lungs and carcasses during the study period in the surveyed abattoirs.

CONCLUSION

This study confirmed the presence of tuberculosis in slaughterhouses in Ngaoundéré, with infected cattle originating from various border areas of the town. It also highlighted that the lungs and carcasses were the most frequently affected, resulting in significant financial losses for butchers. These findings raise food safety concerns in Ngaoundéré and indicate a potential risk of zoonotic transmission of the pathogen.