Mink farmers in the Netherlands have been dealing with outbreaks of coronavirus but it’s not the workers that are sick, it’s the animals. Cases have been confirmed on at least nine mink farms since April and there are two instances where the mink may have passed the virus to humans. Of course the science is still out on all this but it does raise some concerns for farmers as there is so much they still don’t understand about the coronavirus.
Health experts have stressed that the chances of animal-to-human transmission is low but the Dutch health ministry believes two humans caught the disease from infected mink on farms where they worked. The Dutch government isn’t taking chances and has ordered the culling of all the mink at the nine farms where animal outbreaks have been found, fearing they could lead to more human infections.
Researchers say there were “strong similarities” between the virus found in the workers and in the minks but there’s not really a way to definitively proof that it jumped from the mink to the workers. All they can say is it’s highly probable. If it is indeed true, it’s the only known case that the virus has spread to humans from animals. It’s certainly not beyond probabilities. After all, they believe the virus originated in animals though that may be impossible to prove as well.
Roughly a dozen animals are known to be susceptible to the virus. Several species, including pet dogs and cats, captive lions and tigers, and now farmed mink are believed to have caught the virus from humans. According to Jürgen Richt, a veterinary virologist at Kansas State University in Manhattan, it is likely that related canids, felids and mustelids, the group that includes mink, could also be susceptible but no one has checked. Lab experiments indicate hamster, rabbits, and common marmosets are susceptible. So far it does not appear that it has been transmitted between species but it could be spreading undetected in some animals that we don’t know about.
Experiments in pigs, ducks, and chickens show that they are not susceptible, but there have been no studies of other livestock animals, such as cows, sheep, and horses. There is a real concern that the if the virus gets established in wildlife or other species that have close contact with livestock, that it could increase the chances of interspecies transmission. It is not uncommon for pathogens to jump between species and authorities in the Netherlands actually think feral cats might be spreading coronavirus between the mink farms.
Animals that have become infected with coronavirus seem to have mixed outcomes, much like humans. Most appear to only have minor symptoms. The Dutch farmers noticed the mink showing respiratory symptoms like runny noses. A few of the animals showed severe breathing trouble. At the two farms where the first cases were reported, the animal mortality rate was two- to four-fold the normal levels and 28 of the 36 mink autopsied had pneumonia. (Sources: Nature, National Geographic, Medical Science News)