Science

1950s superbug re-emerges as 'souped-up' MRSA

Genetic study of today's community-acquired MRSA superbug suggests it evolved from resistant bacteria that first emerged in Canada in 1950s.

Today's MRSA superbug that is spreading through communities can be traced back to antibiotic-resistant bacteria that first emerged in the 1950s.

The first examples of penicillin-resistant Staphylococcus aureus type 80/81 were isolated in Canada and Australia in 1953.

Mark Enright of the University of Bath in the U.K. and his team sequenced key genes from the decades-old bacteria.

MRSA and hospital hygiene

Although deaths from MRSA superbugs have occurred at the same time hospital cleaning staff are being outsourced in the country, an editorial in The Lancet notes this is merely a circumstantial link.

The editorial comments on how political parties in the U.K. have seized on public fears over unclean hospitals.

"This tit-for-tat political posturing has certainly helped keep health in the public eye," the editorial reads. "But none of these policies reflect the real failure in U.K. hospitals: non-adherence to basic infection control.

Evidence shows that housekeeping practices are unlikely to have an overall effect on transmission of MRSA unless essential infection-control practices – the use of gloves and hand hygiene – are prioritised. But this is rarely the case."

At the time, the microbes caused skin lesions, sepsis and pneumonia in children and young adults worldwide.

Hospital- and community-acquired infections waned as doctors began prescribing the antibiotic meticillin in the 1960s.

By comparing the 1950s samples to the same regions of genes from a community-acquired MRSA in England and Scotland today, the researchers found a match.

Nearly all of the samples were identical. Bacteria from both time periods also shared the same highly-virulent toxin.

The results suggest today's community-acquired MRSA evolved from the earlier type, which evolved resistance to meticillin in the last 30 years or so.

"We have shown that 80/81 and its souped-up community-acquired MRSA descendent share many of the same features, which explains why the 1950s pandemic was so successful," Enright said in a release.

Writing in the April 2 issue of the medical journal The Lancet, the team warns the community-acquired superbug may spread faster and be more widespread than expected.