MRSA
What is it?
MRSA (methicillin resistant Staphylococcus aureus) is now killing more people in the United States each year than HIV/AIDS. It is a type of Staphylococcus aureus a common bacterium, which lives harmlessly on the skin or in the nose of 20-40 per cent of people that has become resistant to a range of antibiotics.
History
MRSA was discovered in the UK in 1961. In the late ’90s it became clear that community acquired MRSA infections were caused by strains of MRSA that differed from the older and better studied hospital associated strains.
Source
In recent years, MRSA cases are increasingly likely to be community rather than hospital acquired and there is evidence to suggest that factory farms are a source. The majority of farmed pigs are kept in crowded conditions where bugs can be easily spread. A recent study found that nearly half of Dutch pig farmers and 39 per cent of pigs in Dutch slaughterhouses were carriers of MRSA. Canadian researchers also found a strong link between pigs and the bug. There’s evidence that people can transmit MRSA to pigs. Human or animal carriers who do not display any signs of illness can spread MRSA.
Symptoms in animals
MRSA infected farmed animals often show no symptoms.
Symptoms in people
MRSA does not usually harm healthy people but those with compromised immune systems or those who have gone through surgery are vulnerable. An infection can occur when bacteria get into the body through a break in the skin and multiply, causing symptoms such as boils, abscesses, styes, carbuncles (large pus filled lumps under the skin), cellulitis (infection of the deep layer of the skin, fat and tissues) or impetigo (highly contagious skin infection that causes blisters). If they get into the bloodstream the result can be more serious infections, such as blood poisoning, septic shock (infection of blood that can lead to organ failure), septic arthritis (severe joint inflammation), osteomyelitis (bone infection), abscesses, meningitis, pneumonia or endocarditis (infection of the heart lining).
Routes of transmission
A new deadly strain M MRSA ST398 M which has been linked to deaths from pneumonia, has been discovered by researchers across Europe. It has been found in both pigs and people. It was first identified in 2003 in the Netherlands, where it is now responsible for 30 per cent of all human cases. In 2008, the Daily Mail reported that MRSA ST398 had been transmitted to people in the UK. Scientists warned that it could already be in the food chain, as none of those infected worked with animals. A small number of tests found the bug in 20 per cent of raw pork samples, 3 per cent of raw beef and 21 per cent of raw chicken. It is feared that this new form of MRSA could pose a far greater risk to the general population than the hospital variant. Once it is in the human population, it lives inside the nose, so coughing and sneezing facilitate its spread.