Prevalence of Tuberculosis in Pigs Slaughtered at Two Abattoirs in Ethiopia13 July 2013
Researchers have found that six per cent of pigs at two abattoirs in Ethiopia were positive for Mycobacterium tuberculosis and therefore that pigs may be a source of infection in humans.
Tuberculosis (TB) is an infectious, granulomatous disease caused by acid-fast bacilli of the genus Mycobacterium, according to Sintayehu Mulugeta Arega of the University of Gondar in Ethiopia and others at Friedrich-Loeffler-Institute in Germany and Addis Ababa University.
The disease affects practically all species of vertebrates. Although mammalian tuberculosis has been nearly controlled in many developed countries, it is still a serious problem in humans and domestic animals including pigs in developing countries.
In Ethiopia, the authors report in a paper in BMC Veterinary Research, the prevalence of TB in pigs is not known. Therefore, this study was designed to estimate the prevalence of TB in pigs in central Ethiopia and to characterise the causative agents using molecular techniques.
The estimated prevalence of TB was 5.8 per cent (49/841). Age and origin of pigs were significantly associated (P<0.001) with the prevalence. In contrast, an association of sex, floor type and water source with the prevalence could not be shown.
Culture positivity was confirmed in 30.6 per cent (15/49) of the tuberculous-like lesions.
Of the 15 isolates, 12 were acid fast positive while five of the latter were confirmed by multiplex PCR as members of the M. tuberculosis complex. Speciation of the five isolates further confirmed that they were M. tuberculosis, belonging to SIT1088 (two isolates) and SIT1195 (one isolate).
The remaining two isolates belong to an identical spoligotype, the pattern of which was not found in the spoligotype database (SpolDB4).
Arega and co-authors concluded that the isolation of M. tuberculosis from pigs suggests a possible risk of transmission between humans and pigs. Hence, establishing feasible control methods is required.
Arega S.M., F.J. Conraths and G. Ameni. 2013. Prevalence of tuberculosis in pigs slaughtered at two abattoirs in Ethiopia and molecular characterization of Mycobacterium tuberculosis isolated from tuberculous-like lesions in pigs. BMC Veterinary Research. 9:97. doi:10.1186/1746-6148-9-97
You can view the full report (as a provisional PDF) by clicking here.
Find out more about tuberculosis in pigs by clicking here.