Doctors believe a new strain of the MRSA superbug that has been found in British cows is infecting humans. The Health Protection Agency, however, says the risk of becoming infected is “very low.”
MRSA, which stands for Methicillin-resistant Staphylococcus Aureus, is a type of staph bacteria that is resistant to certain antibiotics, such as penicillin. It is most often found in hospitals, where these and other antibiotics and disinfectants are used on a regular basis.
The doctors who discovered the strain found the bacteria are resistant to most antibiotics, as is the case with most MRSA strains. New MRSA is very genetically different, and further research showed the strain was also appearing in humans, which has doctors very worried.
Environmentalists believe the so-called “new MRSA” is a result of the overuse of antibiotics by dairy farmers. Farmers use antibiotics to treat mastitis, or inflammation of the mammary gland, in cows. Cows often get mastitis as a result of being fed corn instead of grass, as well as being confined in close and often unsanitary quarters. The Soil Association, the UK’s leading organic organization, has since called for a ban on antibiotic use in farming.
A spokesman for the Department of Health said the new strain of MRSA is rare in the UK, and is not causing infections in humans. It has infected fewer than 100 people a year but Dr. Mark Holmes of Cambridge University, who led the research on new MRSA, says the numbers appear to be increasing.
As a precaution, the Advisory Committee on Antimicrobial Resistance and Healthcare Associated Infection (ARHAI) will be reviewing the research and considering safety issues.
A spokesman for the Food Standards Agency said the study did not provide evidence that humans were contracting MRSA from cattle (by drinking milk), since the majority of cow’s milk is pasteurized, which “destroys all types of MRSA.” He did not, however, offer an explanation as to what could be causing the outbreaks.