The MRSA staphylococcus is an example of a pathogen, the likes of which are often called superbugs. These are resistant to most antibiotics and can cause serious infections.
“In the case of MRSA, these bacteria have also spread in hospitals almost world-wide,” says Jukka Corander, professor at the University of Helsinki, who was a member of the international research team that mapped several millennia of the evolution of the staphylococcus.
In their extensive study, the researchers sequenced whole genomes of the superbugs from a large sample from different animals as well as humans, and were able to study the DNA changes that helped the bacteria to adapt to new host organisms during thousands of years.
First, there were humans
Based on genome analysis, humans were most probably the original hosts to these superbugs, and judging from DNA changes, the ability to colonise domestic animals appeared in an age when the first animals were domesticated to become livestock on farms.
Read more at University of Helsinki
Image: This is a cow. (Credit: Univ. of Helsinki)