Unravelling the Genetics of Drug-Resistant TB in Argentina

Tuberculosis (TB) has reclaimed its position as the world’s leading infectious killer, attributed to approximately 1.3 million deaths in 2024 alone according to the World Health Organization. While standard therapies are generally effective, the emergence of extensively drug-resistant (XDR) strains poses a severe challenge to healthcare systems. These infections require prolonged, costly treatment and often result in a guarded prognosis.

In a detailed study, researchers applied whole-genome sequencing to characterise XDR-TB strains circulating in Argentina between 2006 and 2015. By comparing genetic variants against global databases, the team aimed to understand the molecular mechanisms allowing the bacteria to survive potent drugs. The analysis revealed a complex landscape: there were no common origins for the most frequently observed resistance mutations.

Instead, the bacteria displayed significant genetic diversity. The researchers identified specific variants in genes such as katG and rpoB that confer resistance to first-line drugs like isoniazid and rifampin. This lack of a single evolutionary path highlights the adaptability of the pathogen and emphasises the critical need for continued research and surveillance to combat this persistent global threat.