THURSDAY, SEPTEMBER 29, 2016

Researchers trace origin of TB strain

Researchers study MDR tuberculosis strain origin | Courtesy of pinterest.com

Scientists recently published results from a study about the origins of the mycobacterium strain responsible for tuberculosis (TB), especially the Beijing lineage, in efforts to develop better treatments and diagnoses for multidrug resistant (MDR) TB in Eurasia.

Researchers studied nearly 5,000 strains from 99 countries, representing the largest collection of strains studied to date. They tested 100 bacterial genomes, tracking their origin and spread.

The genetic study shows that the Beijing lineage of TB began approximately 7,000 years ago in northeastern China, Japan and Korea. From that region, TB spread from east to west.

During the industrial revolution and World War I, Beijing TB first expanded its bacterial population. Experts state that these changes were due to increased human population and poverty, both attributes of those historical times.

During the 1960s, TB briefly declined due to antibiotic treatments, but it multiplied again in the 1980s when HIV/AIDS and multidrug resistance became more widespread.

The team has discovered that the bacteria has had many variations that parallel important events in human history. For example, two MDR strains (cloned from the East Asia lineage) began to spread at the same time as the former Soviet Union’s public health system ended. These facts support the importance of controlling TB.

Tuberculosis kills approximately 1.5 million people each year, and its strains continue to become more resistant to drugs. Using this genomic sequencing, researchers can determine how to best treat and diagnose MDR TB.

The research team included scientists from the Centre d'Infection et d'Immunité de Lille (CNRS/Institut Pasteur de Lille/Inserm/Université de Lille), the Institut de Systématique, Evolution, Biodiversité (CNRS/Muséum national d'Histoire naturelle/UPMC/EPHE), and other nations. The study was originally published in Nature Genetics on January 19.