Experts continue blood sample testing amid elephant TB concerns


Reitumetse Makwea, The Citizen 

Date Published
‘We have this ongoing programme to get a big enough sample so that hopefully we can have confidence to say that it is an issue or it isn’t.’

Although there is no evidence that elephant infections and deaths from tuberculosis (TB) which have been reported worldwide are currently creating a crisis in Kruger National Park (KNP), experts are continuing blood sample testing to screen the larger part of the elephant population.

Following a sample extraction and testing earlier this year, KNP’s Veterinary Wildlife Services senior veterinary manager Dr Peter Buss and his team conducted another sample testing due to concerns that elephants in the park were still at risk of human-borne TB, after one was killed by the disease in 2016.

Buss said the ongoing research programme to test at least half the elephants in the park was crucial to determine whether or not the human TB which was found in one of the elephants previously was a big problem or if they could rule out the possibility of a crisis in the future.

“We have a huge population of elephants, about 30 000 elephants. We have this ongoing programme to get a big enough sample so that hopefully we can have confidence to say that it is an issue or it isn’t,” he said.

“But the results to date suggest that it isn’t, because we haven’t found any other elephants with TB.”

Buss also said that following a study conducted by Stellenbosch University’s Animal Tuberculosis Research Group, South African National Parks and the San Diego Zoo Wildlife Alliance in the US tested samples from 437 rhinos collected from 2016 to 2020 in KNP and they would also extend the research to other animals in the future.

The largest study conducted on a free-ranging population of rhinos revealed an estimated prevalence of M.bovis infection of 15.4% in black and white rhino populations in the park. Buss also said a lot of work to get baseline information and data on what was going on with TB in the park was now under way.

This meant that in the future they could start reflecting and conclude that the situation was deteriorating, was stable, or the disease had disappeared.

“The effects of the disease is not like Covid or HIV, where you see the results almost immediately, it can take decades for it actually to express itself completely,” Buss added.

“We know certain species are getting the disease and certain individuals get sick. But what we’re not sure about at this point is how’s that going to influence the population of these animals?

“Will it affect our buffalo population, our lion population and so forth.”

Kruger National Park veterinary technologist Tebogo Manamela said apart from TB there were many other bacterial diseases found in the park. These included brucellosis, anthrax and parasitic diseases from parasites and ticks as well as viral diseases.

South African research chair in animal tuberculosis at Stellenbosch University professor Michelle Miller previously said they were hoping to get more information to help them better understand how the animals were infected, and how it would impact on them in the long term.

“We didn’t think that elephants were necessarily affected by tuberculosis, such as buffalo and lions are, but since that time we have developed a testing programme to look for the bacteria in respiratory secretions,” Miller said.