Isolation and Molecular Characterization of<i> Mycobacterium Africanum</i> from the Sputum of Butchers in a Municipal Abattoir in

Abstract

Tuberculosis (TB) caused by the Mycobacterium tuberculosis complex (MTC) remains a major public health concern due to its high rate of person to person transfer as well as a high level of morbidity and mortality. The risk factors for transmission of zoonotic TB to humans are close physical contact with cattle, consumption of unpasteurised milk and milk products and unhealthy meat processing by butchers are common in developing countries like Nigeria. However, the circulating MTC among the occupationally exposed are unknown therefore the need to determine the prevalence of tuberculosis and to characterize the mycobacterial species in them. A crosssectional study was conducted among butchers, cattle traders and herders in Bodija Municipal Abattoir, Akinyele International Cattle Market and some herds respectively. Using systematic random sampling, 93 sputum samples were collected and analyzed by culture, Mycobacterium Genus Typing as well as Deletion Typing (Multiplex Polymerase Chain Reaction (PCR)). Of the 93 sputa collected, two (2.2%) were positive for mycobacteria by culture which were confirmed to be Mycobacterium africanum by molecular characterization. These bacilli were isolated from two butchers; one of which had the habit of eating raw meat and cherish ‘wara’ (a local soft cheese made from milk). The isolation of M. africanum from butchers in this study raises public health concern on the contamination of the meat processed as well as highlights its importance in the epidemiology of tuberculosis in Nigeria.