Scientists in Rwanda have discovered a new Tuberculosis strain which is “resistant to key drugs”, the Rwanda Biomedical Center (RBC) said on Tuesday.
The new Tuberculosis strain, known as Lineage 8 (L8), was “found by chance in Rwanda,” and is seemingly restricted to the African Great Lakes region.
This discovery is described as a “missing link” in the evolution of one of the world’s oldest and deadliest pathogens, the statement said.
Jean-Claude Semuto Ngabonziza, a researcher and the lead author, said understanding the new lineage tells scientists more about how TB pathogen adapted to the human host and managed to spread worldwide.
“As this strain seems not to be spreading as much as other known TB strains, further and deeper studies of this strain will likely inform TB control and help towards finding effective vaccine and cure,” he said in the statement.
Tuberculosis is one of the oldest pathogens to affect humans with several different strains or ‘lineages,’ according to scientists.
There are about six known lineages for over a decade and a seventh was discovered in Ethiopia about five years ago.
Now scientists have found an eighth lineage in Rwanda and Uganda, which seems to be much older than the other lineages and could be a missing link in the evolution of what causes TB, the RBC said.
It noted that remarkably, the strain is already resistant to key drugs in modern treatment of TB yet it seems to infect far fewer people than other strains.
“Despite massive screening, no additional L8 strain was identified. The Rwandan strain is the sole viable L8 strain identified so far.”
The research work was done in collaboration of the Rwanda Biomedical Centre, the Institute of Tropical Medicine in Belgium, the University of Bradford in UK, the Swiss Tropical and Public Health Institute in Switzerland, and the Centre National de Recherche Scientifique in France.
The findings have been published in the Nature Communications, a sister lineage of mycobacterium Tuberculosis Complex discovered in the African Great Lakes Region. At least 1.5 million people died of TB in 2018, according to the World Health Organization.