Photo used for illustrative purpose.

While persistent cough has been a hallmark symptom of tuberculosis, there should be new ways identified to diagnose the world’s most deadly infection as a new study recently showed a majority of the patients do not have the common symptom, this was reported by IANS.

The study, published in the journal Lancet Infectious Diseases, analysed data on more than 600,000 individuals in Africa and Asia. The results showed that 82.8 per cent people with tuberculosis had no persistent cough and 62.5 per cent had no cough at all.

The infection is predominantly transmitted by coughing, but probably also through simply breathing, said researchers from the Amsterdam University Medical Center (UMC) in the Netherlands.

“Our results indicate the probable reason why, despite huge efforts to diagnose and treat the disease, the tuberculosis burden across Africa and Asia is hardly declining. We already knew that there was a giant gap between the 10.6 million who got ill with tuberculosis and the 7.5 million cases that were registered by health authorities in 2022,” said Frank Cobelens, Professor of Global Health at Amsterdam UMC, the news agency underlined.

“A persistent cough is often the entry point for a diagnosis, but if 80 per cent of those with TB do not have one, then it means that a diagnosis will happen later, possibly after the infection has already been transmitted to many others, or not at all,” he added.

Further, the analysis of national monitoring schemes in 12 countries showed similar results. While the majority lacked cough, more than a quarter of those with TB had no symptoms at all — these were seen more in women than men.

Also a quarter of the patients without cough showed high loads of bacteria in their sputum and were probably highly infectious.

“When we take all of these factors into account, it becomes clear that we need to really rethink large aspects of how we identify people with TB. It is clear that current practice, especially in the most resource-poor settings will miss large numbers of patients with TB. We should instead focus on X-ray screening and the development of new inexpensive and easy-to-use tests” Cobelens said.

Meanwhile, a report by the Institute for Health Metrics and Evaluation (IHME) of the University of Washington’s School of Medicine, titled “Global Burden of Disease, Injuries and Risk Factors Study (GBD) 2021 says that in an overwhelming majority of countries the fertility rate or birth rates would fall which would make sustaining the populations difficult.

That is, the demography would change in such a way that there would be increase in the number of the aged, there would not enough young people to take up jobs and run the economy, and the burden of taking care of the aged would increase. According to the report, 76 per cent of the countries, that is 155 out of 204, would witness decline in the total fertility rate by 2050, which is also known as the replacement rate, and this could lead to economic instability as well.

The crisis would deepen by 2100 when in 97 per cent of the countries, that is 198 of 204 countries, there would be fall in the total fertility rate. There will be only six countries, majority of them in sub-Saharan Africa, where there would be population boom. In 2021, 29 per cent of the babies were born in sub-Saharan Africa.

And by 2100, this would increase to 54 per cent. This situation would require a change in migration patterns, where people from the relatively crowded countries would have to be moved to those countries where there is a decline in population, and this has to be compensated through migrations.