Yes, the Coronavirus is Mutating, and That’s No Reason to Freak Out
There is a new variant of COVID-19 circulating in the UK, but there is no reason to worry or panic: the new variant may spread faster but it is not more deadly and there is no reason to believe the vaccines won’t work to stop it.
On December 13, Public Health England confirmed that they identified a variant in 1,108 cases of COVID-19, which UK Prime Minister Boris Johnson said “may be up to 70 percent more transmissible than the earlier strain.”
While we cannot be absolutely sure about the transmissibility just yet (are the higher case numbers due to a more infectious strain, or human behavior?), there is no denying that cases with the variant are exploding in London, now accounting for 60 percent of cases.
Here’s what we know so far.
Will the vaccines still work?
A mutation in a virus that has killed more than 380,000 in the United States and 1.7 million people worldwide sounds like a god-must-really-hate-us turn of events at the end of this Hell year, but don’t worry: scientists expected and prepared for the virus to mutate.
“It’s mutating at the rate we expect it to,” said Melissa Nolan, PhD, assistant professor of epidemiology at the University of South Carolina’s Arnold School of Public Health.
We have seen other mutations in COVID-19 already. A study in Houston, Texas, showed that the strain infecting people in June and July was different than the one in March and April.
The mutation doesn’t mean we have to give up on our vaccine dreams. “It is not an unexpected setback; we anticipate this RNA virus to mutate, albeit slower than the influenza virus,” said S.S. Vasan, the COVID-19 Project Leader at Australia’s science agency, the Commonwealth Scientific and Industrial Research Organisation.
The mutations in the UK variant are mutations to the spike protein, the key that lets it open the door to the cells. Vasan’s team studied a similar spike mutation and showed that the vaccines are unlikely to have any trouble with even the mutated form of the spike protein.
This is by design: the vaccines are engineered to create an enormous immune response to the entire spike protein, so that the virus will have to accumulate many more mutations to escape it.
Don’t be surprised, though, if such vaccine escape happens one day. “As we put selective pressure on the virus with new therapeutics or vaccines, evolution will ‘search’ for a solution by selecting new variants of the viral RNA genome. We may have to be prepared to adapt the vaccines to emerging new variants, as we do for influenza,” said Lucio Miele, MD., PhD, chair of the department of genetics at the Louisiana State University Health Sciences Center New Orleans.
Is the new variant more deadly?
“No, any changes to the biology of the virus are likely to be influencing how transmissible it is, not how deadly it is,” said David Robertson, PhD, head of viral genomics and bioinformatics at the Institute of Infection, Immunity and Inflammation at the University of Glasgow.
The new variant likely first appeared in September, but got onto the public health radar in November, when public health researchers were investigating the persistently high cases rates in Kent. By December 13, UK officials were able to confirm 1,108 cases of the mutated virus.
That means we know this new variant of COVID-19 pretty well and the good news is that it isn’t any more deadly. Chris Whitty, the chief medical officer of England, said in a statement on Saturday, “There is no current evidence to suggest the new strain causes a higher mortality rate or that it affects vaccines and treatments although urgent work is underway to confirm this.”
If the new variant were more deadly, we would know by now. “This is a work in progress, but the dataset of positive cases with the mutation is now huge and there would have been plenty of opportunity to see any disproportionate effect on severe or lethal cases, but that hasn’t been the case,” said Danny Altmann, professor of immunology at Imperial College London.
But what about new strains making for more severe disease?
One concern that’s been floated is whether the appearance of new strains of COVID-19 will lead to something called antibody dependent enhancement.
Antibody dependent enhancement is very rare and happens when there are multiple strains of a virus circulating and someone gets infected for a second or third time with a different strain of the virus.
“The way that viruses get into our cells is through a lock and key. Think of the spikes as a kind of key going into different doors to see if they let them in. With antibody dependent enhancement, they have the master key and can get into any door they want,” says Nolan.
The classic example is Dengue fever. If someone is infected once with Dengue fever but then infected with a different strain for a second or third time, the antibodies in the body will mistakenly attach to the new look virus and sneak it into cells—making the disease far worse than it would be on its own.
“The virus is able to get inside the locked door and hide from the cameras,” says Nolan.
While antibody dependent enhancement has been a problem for coronaviruses, there is no evidence yet that the virus has mutated significantly enough for it to be a problem for COVID-19.
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