The coronavirus has counted thousands of mutations since the outbreak over a year ago. The most famous mutant is the British. But South African, Japanese and Brazilian variants also emerge. How many mutants are there worldwide and how dangerous are they?
“ Coronavirus mutates at the assembly line”, knows veterinarian and researcher Reina Sikkema from the Rotterdam Erasmus MC. “It has a genetic code of about 30,000 ‘letters’ in which mutations always occur.”
Some mutations deviate so much that they are also examined more accurately. “Certain variants may leave their mark on important characteristics of the virus, such as the infectiousness and the degree of evasion of our immune responses. That‘s why around five variants are now being watched worldwide,” explains Chantal Reusken, virologist at RIVM.
What corresponds to all mutations monitored is the N501Y mutation of the so-called S-gene. The S-protein, also known as spike protein, is a protein on the surface of the coronavirus that binds to ‘cell receptors‘. Many antibodies also bind to this spike protein. This will allow the virus that gets stuck in our airways to adhere better.
The D614G mutation is the most dominant mutant, which has displaced the original virus from China. This variant is most common in Europe.
“ Mutations can be seen as branches in a tree,” explains Chantal Reusken. “You have the D614G mutation, but we have not given it a (country) name. You have so many variants, all of them are marked in the branches of the tree.”
The British variant
The variant known as the British corona variant, also known as the B.1.1.7, appears more contagious and may eventually overgrow the other dominant variant (D614G).
British and Danish studies show that the British mutant is spreading 40% to 70% faster than the coronavirus we have so far.
“ The British variant most research has been done because in the UK many samples determine the genetic code, and there are many researchers and money available to study the spread of this variant. These studies are even less advanced in Brazil and South Africa,” points out researcher Sikkema.
The consequences of, for example, the British mutant can be great, show CCEit on 3 in these five images:
The South African variant
The South African variant is the most feared variant: experts are not sure whether the South African variant is susceptible to the vaccines that are now being produced.
“ The South African and the Brazilian variant have a mutation that may affect the efficiency of immune reactions. That mutation is called E484K, and it’s also in the South African and both Brazilian variants. This is now being investigated by WHO and vaccine producers, Pfizer for example,” says virologist Reusken.
The Brazilian and the Japanese variant
In Brazil, two mutants have been found, which, like the British and South African variant, seem to be more contagious. Also in the Brazilian variant there is a mutation of the spike protein.
The Japanese variant is not actually Japanese, but Brazilian, says researcher Sikkema. “The variant found in Japan is in fact the Brazilian variant, which is now increasing there.”
Finally, can we expect new variants, for example from Iceland or Mongolia? “That is possible,” says virologist Reusken. “This can happen in other countries, but also here if the virus goes from man to animal species again. For example, through mink, a variation can develop that can have a great influence. Or because of the increasing pressure on the virus due to the roll-out of vaccinations and the introduction of antiviral therapies.”