Review of Diagnostic Tests for Detection of Mycobacterium bovis Infection in South African Wildlife

Abstract

Wildlife tuberculosis is a major economic and conservation concern globally. Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis), is the most common form of wildlife tuberculosis. In South Africa, to date, M. bovis infection has been detected in 24 mammalian wildlife species. The identification of M. bovis infection in wildlife species is essential to limit the spread and to control the disease in these populations, sympatric wildlife species and neighboring livestock. The detection of M. bovis-infected individuals is challenging as only severely diseased animals show clinical disease manifestations and diagnostic tools to identify infection are limited. The emergence of novel reagents and technologies to identify M. bovis infection in wildlife species are instrumental in improving the diagnosis and control of bTB. This review provides an update on the diagnostic tools to detect M. bovis infection in South African wildlife but may be a useful guide for other wildlife species.

Keywords: Mycobacterium bovis; South African wildlife; bovine tuberculosis; cytokine release assays; diagnostics; direct detection of mycobacteria; gene expression assays; immunological assays.

Figure 1

Index cases of Mycobacterium bovis infection in free-ranging wildlife species in South Africa over the last century (35). Species correspond to the superscript numbers in Table 1.