A high level of hygiene ensures that as little MRSA CC398 as possible is transmitted from livestock farms to the surrounding society, according to the Danish Pig Research Centre. To limit the transmission of MRSA CC398 it is therefore crucial that everyone working on pig farms are aware of their responsibility in this regard.

As of 1 October 2014, all Danish farmers with a health advisory agreement must implement a biosecurity protocol and must have an entry room where staff and visitors can wash their hands before leaving the premises. These requirements will decrease the risk of transmitting MRSA bacteria from livestock housing to the surrounding society.

What is MRSA?

MRSA are Staphylococcus bacteria resistant to the antibiotic called methicillin (Methicillin-Resistant Staphylococcus aureus). Nevertheless, all humans who are infected with MRSA can be treated as there are other types of antibiotics that are effective against MRSA.

MRSA is known in Denmark since the mid-1960s, and has so far only affected humans. A few years ago, a new type was detected: MRSA CC398. It is found in livestock, in particular in pigs, calves, poultry and horses. In Denmark, it is primarily found in pigs.

Pigs carry MRSA CC398 on the skin or in their snout. Inside the pig house, MRSA CC398 is present in dust, on all surfaces and in the air. MRSA CC398 does not affect the well-being of pigs.

MRSA is considered widespread among Danish pigs; Pig Research Centre estimates that MRSA CC398 is found on more than 50 per cent of all Danish pig farms. In the Netherlands, Germany, Spain and Italy, all pig farms are considered infected with MRSA, and have been so for several years.

MRSA CC398 may cause disease in humans, even though many are “healthy carriers” of the disease. MRSA CC398 may, just like other staphylococcus bacteria, cause infections, in particular skin infections with ulcer and abscesses.

In rare cases, infection may cause blood poisoning, and deaths have been recorded in Denmark. Records show four deaths up to August 2014 that can be associated with MRSA CC398; in that same period, 700 people have died from infections associated with other staphylococci.