Sneaky Superbugs

Denmark may not strictly curate its pigs’ health, but not all countries follow suit. Nearby Norway, for instance, carefully maintains its herds’ disease-free status through extensive screening and a tight lock on live imports. Nevertheless, several outbreaks of LA-MRSA overtook Norwegian pigs even after the introduction of import bans – so the authorities began asking: how?

The answer, it seems, lies in a novel transmission route. Humans – namely, laborers who had previously worked on Danish pig farms – likely brought the CC398 strain of LA-MRSA with them to Norway, where they passed it on to the livestock they handled (1). Although those workers, like most humans, were able to carry the bacterium without ill effects, some are not so lucky. The same strain has caused numerous illnesses and even six deaths in Denmark, where it is endemic. Patients need not have had direct contact with livestock to contract the disease; it can be transmitted through contaminated meat as well.

Although Norway’s strict protocols have thus far prevented CC398 from becoming widespread, this new mode of transmission may mean that the country needs to crack down even more – and in fact, mandatory screening of farm workers has already been suggested. One thing is certain: the ability to transfer infections back and forth between species reinforces the need for both human and veterinary medical specialists to speak out for better stewardship wherever possible.