November 27, 2020

I, Science

The science magazine of Imperial College

By Keegan Schroeder

Just as we are beginning to see the glimmer of light at the end of a very troublesome tunnel, we hit another small furry bump in the road. After spreading from human farmers, a new strain (variant) of Coronavirus has evolved in minks, a relative to ferrets that is widely farmed for their fur, with over 214 people in Denmark reportedly having been infected by the new strain.

The news has attracted the attention of the World Health Organisation (WHO) who are now conducting a biosecurity risk assessment as millions of minks are being slaughtered.

Minks by Jo-Anne McArthur on Unsplash
Mink Farm by Jo-Anne McArthur on Unsplash

This concern arises due to the way in which these mink farms are a catalyst for viral mutations. The new environment and selective pressures of a mink host, and the close proximity of thousands of minks allowing for a high viral reproduction number (R), causes mutation to occur at a faster rate which could potentially produce a COVID-19 strain that is far less susceptible to current treatments.

Of particular concern is any change to the structure of the spike protein present on the surface of the coronavirus that gives it its name. The spike protein is what allows the virus to infect human cells and is the major target for the immune system if correctly prompted by a vaccine. Change the spike protein and you will likely need a new vaccine which would be a devastating setback.

In a recent letter to the journal, Science, three scientists, from Denmark, China and Malaysia, wrote: “It is urgent to monitor, restrict, and – where possible – ban mink production.”

The decision to cull the minks and to rigorously prevent the spread of this new strain has been called a “precaution” and scientists are waiting on evidence that will show the nature of the mutations new strain which will require sharing of the genomic sequence.