In a unique "microbial safari," GenPath Africa colleagues Megan Matthews, Wynand J. Goosen and Michele A. Miller from Stellenbosch University have discovered the first evidence that the bacteria causing animal tuberculosis (TB) can persist in the soil of one of Africa’s largest game reserves. Their research provides a new perspective on how this pathogen might move through wild ecosystems.

What is this publication about?

Researchers set out to determine if Mycobacterium bovis (M. bovis)—the primary cause of animal TB—could be detected in the environment of the Kruger National Park (KNP), where the disease is endemic in several wildlife species. The team collected 180 soil samples from locations near water sources where animals frequently congregate. By using a combination of advanced molecular tools, including Sanger amplicon sequencing and region of difference (RD)-PCR, they screened the soil for bacterial DNA. They successfully identified DNA from the Mycobacterium genus in 44 samples and confirmed the presence of M. bovis DNA in two of the sampling sites.

Why is this important?

For a long time, it was believed that animal TB was spread almost entirely through direct contact, such as an infected animal coughing near another or through the sharing of saliva. This study provides the first definitive evidence that M. bovis DNA is present in the soil of KNP, suggesting that the environment itself may act as a hidden reservoir for the bacteria. This is particularly concerning because KNP is home to many threatened and endangered species, such as the black rhinoceros and African wild dog, which are vulnerable to TB infection.

How can this make a difference?

By proving that the pathogen DNA is detectable in soil, this research supports the development of non-invasive surveillance tools. Instead of having to capture and test wild animals directly—which is expensive, stressful, and risky—scientists may eventually be able to monitor the health of a whole ecosystem by sampling the environment. These insights are vital for developing more effective disease management strategies to protect South Africa’s unique biodiversity and to better understand the risks at the interface where wildlife, livestock, and humans meet.

M. C. Matthews, M. E. M. Toorians, T. J. Davies, R. D. Stewart, W. J. Goosen, and M. A. Miller, "A microbial safari: finding evidence of Mycobacterium bovis DNA in soil from the Kruger National Park, South Africa." Microbiology Spectrum, 2025; 13. doi:10.1128/spectrum.01658-25.