The bacterium responsible for tuberculosis is evolving in response to HIV infection, with potentially serious implications for vaccine design.

It is well known that antibiotics and vaccines affect the evolution of bacteria, often leading to treatment-resistant strains.

Now researchers have shown the bug responsible for TB, Mycobacterium tuberculosis, can evolve in response to HIV, a finding, they suggest, that could influence the design of TB vaccines for regions where HIV is endemic.

HIV and TB co-infection is very common. According to the World Health Organisation (WHO), out of 9.6 million new cases of TB in 2014, 1.2 million were people with HIV.

The current study was carried out by a team led by Anastasia Koch from the University of Cape Town, and is publishedin the journal Molecular Biology and Evolution.

The researchers’ hypothesis draws on Darwin’s theory of natural selection, which proposes that changes in the environment can favour or disadvantage certain characteristics of organisms. The researchers point out that by routing the unfortunate human host’s defences, HIV dramatically alters the immune environment of TB and plausibly introduces selection pressures.

Read the full article in Cosmos magazine here