The evolution and contagion methods of the Mycobacterium tuberculosis bacterium which causes tuberculosis were under scrutiny in a major international study with particular focus on Russian tuberculosis patients.
Inefficient treatment bolsters bacteria
Unlike the bacteria causing traditional tuberculosis, most of the recently discovered tuberculosis strains displayed both a powerful resistance to existing drugs and specialised genetic mutations, making them more resilient and more contagious.
These discoveries reveal the biological reasons why the programmes aiming to treat tuberculosis and prevent its spread in Eastern Europe have proven ineffective. For example, researchers suggest that treatment with kanamycin could even promote the spread of bacteria capable of causing the disease.
Comprehensive source material
The study sequenced the genome of the tuberculosis bacterium based on 1,000 patient samples, encompassing the forms of bacterial strains found both in Russia and around the world.
“The genetic material was unparalleled in scope, and therefore highly credible,” states Professor Jukka Corander from the Department of Mathematics and Statistics at the University of Helsinki. Corander was responsible for the population genetic analysis of the material.
The Russian bacteria population mainly consisted of mutated strains known as the Beijing and Euro-American lineages. A majority of the samples represented multi-resistant strains of the Mycobacterium tuberculosis.
Resistant tuberculosis strains spreading in the EU
The same new resistant tuberculosis strains were also discovered in patients in the UK. The researchers believe that tuberculosis could spread extensively within the European Union unless sufficient preventative steps are taken in time.
Tuberculosis is the second most common cause of infection-related death in the world. In 2011 alone, it is estimated that 8.7 million new people were infected and 1.4 million died from the disease.