Flesh-eating Bug that You can Catch on the Bus or Train

• Strain of MRSA from the U.S. causes large boils and is resistant to several front-line antibiotics

• Survives on surfaces so can be picked up on public transport

By Lauren Paxman

A flesh-eating form of pneumonia that is easily passed between healthy people on public transport is spreading across the UK, experts have warned.

The deadly strain of MRSA called USA300 passes easily through skin-to-skin contact. It can also survive on surfaces and so has the potential to be picked up on crowded buses and tubes.

It was first seen in the U.S but cases are now being reported in the community and not just hospitals in Britain.

USA300: The deadly MRSA strain can cause large boils on the skin

Dr Ruth Massey, from the Department of Biology and Biochemistry at the University of Bath, said extra vigilance was required around this and similar MRSA bugs known as PVL-positive community acquired strains.

USA300 is resistant to treatment by several front-line antibiotics and can cause large boils on the skin. In severe cases, USA300 can lead to fatal blood poisoning or a form of pneumonia that can eat away at lung tissue.

Dr Massey said there were 1,000 cases of PVL-positive community acquired MRSA in England in the last year, of which 200 were USA300 strains.

‘These community-acquired strains seem to be good at affecting healthy people – they seem to be much better than the hospital ones at causing disease.

‘They don’t rely on healthcare workers moving them around, which the hospital ones seem to.’

Dr Massey said USA300 is ‘a really big issue in the U.S. and it’s starting to emerge here.

‘But hopefully because we are aware of it and are working to understand it, it won’t become as big of a problem (in the UK).’

In a new research paper published in the Journal of Infectious Diseases, Dr Massey and colleagues analyse the way community-acquired MRSAs are able to adapt and fine tune themselves to spread outside of hospitals.

MRSA bacteria in hospitals has not been able to migrate into the community in the same way.

Dr Massey said: ‘Our research found that the composition of the cell wall of the bacteria is critical to the community-acquired bacteria being more toxic.

Different danger: MRSA bacteria in hospitals have a different kind of cell wall to community-acquired MRSA strands which have evolved further

‘The ability of the MRSA bacteria to secrete toxins is one of the main ways it causes disease.

‘Using a sensing system, it carefully controls when it switches on its ability to do this, so as not to cause disease until it is firmly established within the human.

‘Many antibiotics target the cell walls of harmful bacteria, and to resist this, the bacteria have to make changes to their cell wall.’

Community-acquired MRSA strains have cell walls that are different to those seen in hospitals, allowing them to sense their environment and switch toxin expression on at the right time. …  MORE AT: THE ENTIRE SOUCRE