Approximate home locations of 10 patients identified to contain Mycobacterium bovisDNA (n = 10, pink dots with patient study identifiers) in their sputum samples. Locations are shownrelative to Hluhluwe-iMfolozi Park, iSimangaliso Wetland Park, Primary Health Care Clinics, and HlabisaDistrict Hospital in Hlabisa Sub-district, KwaZulu-Natal Province, South Africa.Credit: Wynand Goosen
Zoonotic Mycobacterium bovis has been detected in people living near a wildlife park in rural South Africa. A study, published in One Health, by a team from South Africa, Switzerland, the United States, the United Kingdom, and Australia, showed that bovine TB has possibly jumped from livestock and wildlife to humans in the area around Hluhluwe-iMfolozi Park in the KwaZulu-Natal province.
This is the first time that the DNA of M. bovis has been isolated from human samples collected in South Africa, despite many reports from elsewhere on the continent. M. bovis is endemic to this conservation area, the country’s oldest game reserve.
The team found detectable DNA of pathogenic MTBC in 20 of the 68 samples tested.
Four of the human samples were found to contain one of two different M. bovis strains, SB0130 and SB1474. The first strain is frequently detected in cattle and wildlife in the region, and the second only in African buffaloes. Wynand Goosen, team member, and a molecular biologist at Stellenbosch University (SU), says this suggests possible recent or historic cross-species transmission at the wildlife-livestock-human interface around the park. The team also recently investigated the presence of M. bovis DNA in water samples collected from shared water sources used by people and animals living on park borders adjacent to the reserve.
“M. bovis DNA in sputum from people living near the reserve underscores zoonotic TB transmission potential in South Africa. The results can have far-reaching consequences for conservation, the livestock industry, and public health,” he warns.
The researchers say their findings highlight the need for integrated TB surveillance, control strategies, and the use of multiple molecular techniques with different sensitivities to curb potential spillover.
“Understanding this spillover into people could help identify the TB ‘missing middle’ — cases of TB infection in humans that are going undetected and untreated. There should be no one-size-fits-all approach for TB surveillance, as M. bovis infections among humans can easily go unnoticed.”
