More than 80% of people suffering from tuberculosis do not have a persistent cough, according to a study, which calls into question current diagnostic tools and screening strategies.
- More than 80% of patients with tuberculosis, the world’s deadliest infection, do not suffer from persistent cough, even though it has long been considered a key symptom of the disease, according to a study with 600,000 people.
- “This means that the diagnosis will be delayed and made later, probably after the infection has already been transmitted to many others – or not at all,” according to Professor Frank Cobelens. “These findings may explain why, despite enormous efforts to diagnose and treat the disease, the burden of tuberculosis in Africa and Asia is hardly decreasing.”
- A quarter of TB patients who didn’t cough at all had “a high load of bacteria” in their sputum, making them “likely very contagious.” The researchers deduced that “the infection is transmitted mainly by coughing, but perhaps also by simple breathing.”
Should we rethink the diagnostic criteria? More than four in five patients with tuberculosis, the world’s deadliest infection, do not suffer from a persistent cough, even though it has long been considered a key symptom of the disease. This is the surprising conclusion of a large study recently published in the journal The Lancet Infectious Diseases.
10.6 million people will develop tuberculosis in 2022
To achieve this observation, researchers from the University Medical Center of Amsterdam and the Amsterdam Institute for Global Health and Development (AIGHD), in the Netherlands, relied on the analysis of data from more than 600,000 people from from twelve countries in Africa and Asia, collected through national health surveillance programs between 2007 and 2020. It appeared that 82.8% of people with tuberculosis did not present with persistent cough, and even that 62.5% did They didn’t cough at all.
“These findings may explain why, despite enormous efforts to diagnose and treat the disease, the burden of tuberculosis in Africa and Asia is hardly decreasing, assures Professor Frank Cobelens, lead author of the research, in a communicated. We already knew that there was a huge gap between the 10.6 million people who fall ill with tuberculosis and the 7.5 million cases that were recorded by health authorities in 2022.” As a reminder, the World Health Organization estimates the number of deaths from tuberculosis at 1.6 million in 2021.
“A persistent cough is often the entry point for a diagnosis, adds the specialist. But since 80% of TB patients don’t have it, that means the diagnosis will be delayed and made later, probably after the infection has already been transmitted to many others – or not at all. “
Tuberculosis “is transmitted by coughing, but perhaps also by simple breathing”
According to the study, apart from the absence of cough, more than a quarter of tuberculosis patients, and the majority of women, had no symptoms (absence of fever, chest pain, night sweats, etc.) . The fact remains: a quarter of those who did not cough still presented “a high load of bacteria in the secretions produced by their respiratory tract” (aka spit), which makes them people “probably very contagious”. Deduction of researchers, “The infection is transmitted mainly by coughing, but perhaps also by simple breathing.”
The team of scientists believes that these new factors require “rethink the way we identify people with tuberculosis”. It would be better, according to her, to concentrate more on “X-ray screening and the development of new inexpensive and easy-to-use tests”.
