Most Common Form of TB Originated Among and Spread By Europeans

Tuberculosis is one of the most common infections you can catch today; at one time in history, it was also one of the most devastating.  While Mycobacterium tuberculosis still takes more lives than any other infectious disease we deal with today, its global toll has been on the slow decline for many decades.  Still, there is a very real threat for TB to make a comeback thanks to antibiotic resistance, according to a study from researchers at the University College London, in the United Kingdom.

Published in the journal Science Advances, this study is actually the most thorough genomic analysis of this most widely spread strain of TB, which is called Lineage 4 TB.  The new information extracted from this study adds significant data to the way we understand not only how this most common strain of TB continues to spread, but also—and perhaps more importantly—where it came from.

This study managed to map the evolution of drug-resistant of antibiotic resistance to determine that drug-resistant strains of the Lineage 4 TB have most spread only among the people of its country of origin. For the study, the researchers took 1,669 DNA samples of the lineage 4 strain taken previously from specimens collected in Europe, Vietnam, Africa, and North and South America.

According to study author Vegard Eldholm, of the Norwegian Institute of Public Health, “Our findings strongly suggest that at least for Lineage 4, antibiotic resistance is a local challenge present in multiple countries and regions, but with a minimal spread between them.”

“Therefore,” he continues, “countries that succeed in halting transmission of resistant strains within their territory should expect to see a massive decrease of drug-resistant TB.”

Most importantly, though, he advises that while we can certainly pinpoint the origin and contained the spread of this most common form of ABR TB, we cannot simply discount its potential spread across international populations. After all, the study examines that the disease might have originated in Europe but it did eventually spread to Asia, Africa, and the Americas when Europeans began exploring [and colonizing] the globe.

In addition, Johns Hopkins Bloomberg School of Public Health epidemiologist David Dowdy—who was not involved in the study—comments that this study could intimate the possibility of more control of the disease. He says, “It means we may be able to control tuberculosis resistance at the local level.”