Prevalence of BTB in Ghana

The true prevalence of BTB in Ghana is not known as data on its occurrence in the different districts and administrative regions of the Veterinary Services Department (VSD) are minimal and are usually gathered from sporadic inspection and research activities.

Most sporadic studies were conducted in the Greater Accra Region (GAR). Between 2005 and 2010, 516 BTB cases were diagnosed at abattoirs and slaughter­houses in Ghana (Amemor 2012). Bonsu et al. (2000) tested a total of 1200 cattle, comprising 747 cows and 400 heifers, all 2-4 years old, and 53 bulls from the GAR using the SIT. Of the 1200 cattle tested, 166 reacted positively to bovine tuberculin, representing an average prevalence of 13.8% in cattle in the district, although the prevalence was as high as 50% in some kraals. All ages of animals and both sexes were affected, but the prevalence in cows was twice as high as that in heifers and in bulls. In another study conducted on four farms from the GAR, a crude prevalence of about 17% was reported (Thoen and Ebel 2006). Additionally, 685 cattle from two dairy farms in the same region were tested; of these, 17 were positive by the tuberculin test, giving a crude BTB prevalence of 2.5% (Asante-Poku et al. 2014). The main difference in the animals used in the later and previous two studies was the husbandry systems used: animals from a dairy farm were included in the later study; while the other two studies involved animals from free-range farms scattered in rural communities. These findings suggest that the control of BTB is more difficult in a free-range grazing system. Within the Accra Metropolis, 145 out of 2886 (5%) cattle slaughtered over a period of 4 months were found to contain BTB-like lesions, most of which were confirmed as being infected by M. bovis by further microbiological analysis (Atiadeve et al. 2014).

Additional information exists for the Volta Region where Ankugah (2000) reported a BTB prevalence of 3.1% in the Ho district even though it was as high as 5.9% in one cluster. Amemor (2012), using a rapid antigen capture assay, analyzed 200 cattle consisting of 14 bulls and 186 cows, and found a prevalence of 19% (38/200) (all females) in the North Tongu district of the same region.

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