How drug resistant TB evolved and spread globally

The most common form of Mycobacterium tuberculosis (TB) originated in Europe and spread to Asia, Africa and the Americas with European explorers and colonialists, reveals a new study led by UCL and the Norwegian Institute of Public Health. TB takes more lives than any other infectious disease and while its global burden has slowly declined over the past decade, the rise of antibiotic resistance (ABR) presents a major obstacle to its control. The study, published today in Science Advances , is the most thorough genomic analysis to date of the most widespread form of TB, called Lineage 4 TB, and significantly adds to our understanding of the origin and subsequent spread of the most common form of TB. The team also mapped the evolution of drug resistant strains to investigate the mechanisms of ABR and found that drug resistant strains of Lineage 4 TB have hardly spread beyond the country in which they originated more recently. "Our findings strongly suggest that at least for Lineage 4, antibiotic resistance is a local challenge present in multiple countries and regions, but with minimal spread between them.