Antibiotic use questioned as new strain of MRSA appears

Pressure is mounting for action to change farm practices after the emergence of a new strain of MRSA in cows and humans.

The discovery of the drug-resistant "superbug", found in contaminated milk, raises concerns about farm use of antibiotics posing a health risk to the general population.

Two leading charities have now called for an end to excessive use of the drugs, which can promote the growth of resistant bacteria.

They echoed claims made by the scientist behind the MRSA find. Dr Mark Holmes, from Cambridge University, said dairy farmers were forced to use the drugs by "tremendous financial pressure" from price-cutting supermarkets.

To maximise milk yields, farmers had to drive their cows "hard", resulting in health problems and greater use of antibiotics, said Dr Holmes.

Experts do not believe milk or dairy products pose a serious health risk because pasteurisation kills MRSA bacteria.

But Dr Holmes said there was "circumstantial evidence" that dairy cows were providing a "reservoir of infection". Farm workers could spread the bug if it got on to their hands or clothing.

Michele Danan, from Compassion in World Farming, said: "There must be something awry in today's farming systems if animals have to be treated with antibiotics on a regular basis."

The Soil Association has also strongly condemned the over use of antibiotics on dairy farms in light of the MRSA discovery.

The new MRSA strain has a different resistance gene to "normal" MRSA, making it impossible to detect using the standard molecular test.

Scientists have identified the strain in around 50 swab samples from people in Scotland, England and Denmark.