Coughs of Cape patients used to develop TB detection app

A patient’s cough being recorded.

A patient’s cough being recorded.

Published Mar 24, 2024


Cape Town - Stellenbosch University (SU) scientists are developing a mobile application (app) that will be able to distinguish a cough caused by tuberculosis (TB) from non-TB-related coughs.

This innovation will be used as a screening tool to determine which patients require further testing, thereby fast-tracking the TB diagnosis process.

The cutting-edge project, called Cough Audio Triage for TB (CAGE-TB), is conducted by researchers in the Clinical Mycobacteriology and Epidemiology (CLIME) Group in SU’s Division of Molecular Biology and Human Genetics, along with partners in Europe and Africa.

“Mobile-based cough audio classification represents a potential holy grail for triage testing, with no specimens collected, negligible cost, and inexpensive smartphones have high-quality microphones and computational power to analyse audio on-device,” said CLIME’s Professor Grant Theron, the lead investigator on the project.

“The CAGE-TB app represents a tremendously exciting opportunity to transform TB diagnosis at scale, ensuring more people are tested, testing itself is done more efficiently, and TB is diagnosed earlier, stopping transmission in its tracks.”

TB is one of the deadliest infectious diseases globally, but many cases remain undiagnosed, particularly in low-income communities, due to outdated screening models. Conversely, many people who do not have TB are tested for it, unnecessarily using scarce resources.

CAGE-TB project co-ordinator Daphne Naidoo said the project will address a critical diagnostic gap in TB.

“CAGE-TB aims to systematically identify people in need of costly yet essential confirmatory testing. The app will transform the process in which potential TB patients are managed upon clinic entry.”

The CAGE-TB project recently received a funding boost of R20 million from the European and Developing Countries Clinical Trials Partnership, which aims to reduce the burden of poverty-related diseases in developing countries through the development of medical interventions.

The research was initiated in 2021 and is based on the CAGE-TB team’s proof-of-concept work which found TB patients have a distinct-sounding cough compared with healthy people and people with other respiratory diseases.

Naidoo stressed that the app will not diagnose TB but will be used for triage. The app will screen patients to establish who are most likely to have TB, and prioritise them for further sputum tests.

“Currently, there is a high level of TB passing through clinics, but these cases are either picked up too late or completely missed. We want to speed up TB diagnosis.”

According to Naidoo, the research is being conducted in two phases: discovery and validation.

“In the discovery phase, data will be collected from a cohort in Cape Town to refine the cough audio signal specific to TB. This involves advanced machine learning methods tailored for TB patient cough audio analysis.

“The validation phase will use the optimised TB audio signature from the discovery cohort to validate the technology in a broader population in Cape Town and Kampala, Uganda.”

Weekend Argus