It’s the breathing, not just the coughing.
Up to 90% of tuberculosis bacteria from an infected person may be carried in aerosols released when they exhale deeply, according to a study by University of Cape Town researchers presented yesterday at the 52nd Union World Conference on Lung Health.
Major revision: The finding overturns long-held beliefs that coughing plays the main role in TB transmission, the Indian Express reports.
It also calls into question the value of symptomatic screening of people believed to be “TB-transmitters,” said lead author Ryan Dinkele.
Rather than waiting to screen people for TB until they show up in a clinic with a wracking cough, the entire population should be screened, Boston University epidemiologist Robert Horsburgh, who wasn’t involved in the research, told The New York Times.
By the numbers: Consider that for an infected person who breathes 22,000 times per day and coughs up to 500, the coughs will contribute as little as 7% of the total bacteria emitted by the person, Dinkele said.
The COVID connection: The research highlights the role of aerosols in transmitting disease, as found with the coronavirus.
“Those of us who are TB people look at Covid and say, ‘Wow, it’s just a sped up version of TB,’” Horsbaugh said.
Largest ever global study of tuberculosis identifies genetic causes of drug resistance – University of Oxford (news release)
MSF clinical trial finds short, effective and safe drug-resistant tuberculosis treatment – MSF
Most resistance-causing mutations in TB have now been identified – The Economist