Scientists have discovered a new type of the potentially deadly MRSA bacteria in dairy cows that is almost identical to one found in hospital patients.
Strains of MRSA, which causes infections in humans and is resistant to many existing antibiotics, have already been found in pigs, poultry and cattle in several other European countries.
However. the study by researchers from Cambridge University, published in the medical journal The Lancet today, is the first evidence of MRSA being discovered in UK farm animals.
In a significant development, the researchers found the new type of MRSA was already infecting humans and believe it is likely to have been transmitted from farm animals to people.
As well as discovering that the new type of MRSA was the cause of infections in humans in the UK, scientists in Denmark and Ireland have also found cases of it in patients in those countries.
Food safety officials this week moved quickly to try and reassure the public saying the risk of contracting the new strain of MRSA through drinking milk was 'extremely low' as the vast majority of cows milk was pasteurised, a process that destroys all types of MRSA.
'Additionally most of the samples of the new strain of MRSA found were in milk from cows with udder infections. Milk from these cows is banned for human consumption,' confirmed a spokesperson from the Food Standards Agency.
However, as the Ecologist reported last month as part of a special report into antibiotics, there are increasing concerns about the spread of deadly antibiotic-resistant infections from animals to humans. In particular, medical experts and campaigners say the overuse of antibiotics in farming is contributing to the ever-increasing amount of antimicrobrial-resistance as bacteria evolve to withstand existing drugs.
EU food safety officials had already predicted back in 2008 that it was likely to the source of some antibiotic-resistant strains of MRSA and E.coli - both potentially life-threatening infections.
Researchers who discovered the new type of MRSA in Irish patients say the findings highlighted how new and potentially deadly-types of MRSA could spread from animals to humans.
'The results of our study and the independent UK study indicate that new types of MRSA that can colonise and infect humans are currently emerging from animal reservoirs in Ireland and Europe,' said Professor David Coleman from the University of Dublin.
Campaigners put the blame for the emergence of new types of MRSA on the overuse of antibiotics on intensive dairy farms where cows are under pressure to produce high levels of milk.
The Soil Association have highlighted the overuse of cloxacillin and cephalosporins - both antibiotics suspected of promoting MRSA and used in dairy farming. Use of celphalosporins in farming has more than quadrupled over the past decade
'This new evidence confirms our long-held view of the importance of absolutely minimising the use of antibiotics especially those closely related to antibiotics used by people,' says Soil Association director Helen Browning.
'In the relentless drive for increased per animal productivity, and under acute price pressure, dairy systems are becoming ever more antibiotic dependent. We need to get farmers off this treadmill, even if that means that milk has to cost a few pennies more. That would be a very small price to pay for maintaining the efficacy of these life-saving drugs,' she says.
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