A new study has suggested that a type of MRSA (methicillin-resistant Staphylococcus aureus) found in humans may have originated from cattle as far back as 40 years or more.
Researchers from the University of Edinburgh, Scotland, analyzed around 40 strains of the bacterium – Staphylococcus aureus, which is capable of building up methicillin antibiotic resistance, leading to MRSA.
Staphylococcus aureus spreads easily in humans through skin-to-skin contact.
The researchers found that at least two genetic subtypes of the bacterium, already present in widespread human MRSA, could be traced back to cattle.
The study, published in the journal mBio, suggests that the bacterium may have passed from cattle to humans by way of direct contact, possibly through people working with farm animals.
Professor Ross Fitzgerald of the Roslin Institute at the university and lead study author, said:
“Human infections caused by bacteria being transmitted directly from livestock are well known to occur.
However, this is the first clear genetic evidence of subtypes of Staph. aureus which jumped from cattle and developed the capacity to transmit widely among human populations.”