Blood test gives early warning of TB danger
BREAKTHROUGH: Researcher Adam Penn-Nicholson, who helped develop the new test in a University of Cape Town laboratory SOUTH African researchers are testing a breakthrough approach that they say could mean the end of the tuberculosis epidemic.
The team at the South African Tuberculosis Vaccine Initiative have developed a test that detects a particular type of “inflammation in the blood”, allowing them to predict up to a year in advance if someone will get TB.
Preventative medication could be prescribed to people who tested positive, said Thomas Scriba, deputy director of immunology at the initiative’s University of Cape Town laboratory.
Four out of five South Africans carry the bacteria that cause TB. Although only one in 100 get the actual disease every year, it still accounts for one in seven deaths in the 15-44 age group.
“We can’t treat 80% of the adult population with preventative therapy,” said Scriba. But “among all those that are conceivably at risk we can now start identifying people who are truly at risk”.
More than 10 000 people are being tested for TB risk with the new technique in Worcester, Durban, Stellenbosch, Rustenburg and Klerksdorp.
The Correlate of Risk Targeted Intervention Study is funded by the Bill and Melinda Gates Foundation and the South African Medical Research Council.
In Worcester, 18-year-old Rashieda Kriel is undergoing preventative treatment after the blood test showed she had a risk of progressing to TB within a year.
“An uncle of mine has TB and an auntie who works with me also has TB,” she said. “Many people in the community have it. It’s in everyone’s bodies, it just takes a certain time until you get it.”
Her mother, Saadiqa Kriel, said she was “fed up” with Rashieda’s uncle because he refused to take medication, drank from the children’s cups and “spits on the ground”.
“He can infect anyone. They say he’s got that difficult [drug-resistant] TB,” said Saadiqa.
“He feels he doesn’t want to go to the day hospital every day, and the injections are painful.”
Two field nurses with the TB vaccine initiative, Anne Swarts and Sophie Keffers, said this attitude was common, and doctors and researchers were often treated with suspicion.
“Many people won’t tell us if there is a TB contact in the household or if someone is on TB medication,” said Keffers.
In 2014, TB killed 38 000 South Africans and 1.4 million people globally, making it the biggest infectiousdisease killer of humans.
Initiative director and principal investigator Mark Hatherill said: “If we get it right, and if we can show that the prevention hypothesis works, then this is something that can be rolled out, given sufficient resources and will of the health services.
“This is something that can really have an impact on the TB epidemic.”
Researcher Adam Penn-Nicholson said results of the trial would be available in 2019.
This is something that can really have an impact on the TB epidemic
STIGMA: Field nurses Anne Swarts and Sophie Keffers say many people will not tell them if there is a TB contact in the house