- The virus that causes COVID-19 has mutated, as expected.
- Two mutations of the virus called variants are worrying health experts.
- There’s currently no evidence the variants will affect the efficacy of the vaccines or cause a more severe illness.
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A few weeks ago, news broke that a more transmissible strain of the coronavirus, the B.1.1.7 lineage, has been circling around the United Kingdom.
The strain, thought to be up to 70 percent more transmissible than the original strain, thrust the United Kingdom into a lockdown. And the B.1.1.7 lineage has already been detected in several locations in the United States.
On Jan. 4, South African health officials announced they, too, have detected a new, seemingly more contagious strain.
It’s no surprise that the coronavirus has mutated — that’s what viruses do. Most mutations are useless, but every so often, a mutation will improve a virus’s ability to infect people.
Given the swift spread of the new variants, experts suspect the new strains contain mutations that make it easier for the virus to bind to our cells.
There’s currently no evidence the variants will affect the efficacy of the vaccines or cause a more severe illness.
Still, more studies are needed to understand the mutations and the impact they could have on the pandemic.
Viruses mutate frequently
All viruses mutate often. Typically, the mutations aren’t functional and have no significant impact on the behavior of the virus.
As viruses mutate, their chance of survival increases. That is, the more diverse a species is, the more chances it has to survive, said Dr. Benjamin Neuman, a virologist at Texas A&M University Texarkana.
“Mostly the changes are bad for each individual virus, but together, a population of weaker but more diverse viruses has a better chance of survival than the same sized population of identical viruses,” Neuman said.
Sometimes, those mutations can improve the performance of the virus, as we may be seeing with the new variants detected in the United Kingdom and South Africa.
“Just like a good engineer can usually find a way to optimize a machine, mutations can change the speed with which parts of a virus work,” Neuman said.
A new strain in South Africa
Called the B.1.351 lineage, the new strain identified in South Africa is thought to be more transmissible.
According to the World Health Organization (WHO)Trusted Source, the variant replaced other leading strains circulating around the Eastern Cape, Western Cape, and KwaZulu-Natal provinces in November.
The strain has also been associated with a higher viral load, further suggesting it’s more transmissible than previous strains.
Some medical experts have sounded the alarm that the variant could potentially be resistant to vaccines or medications.
There’s no evidence that suggests the new variant in South Africa won’t respond to the vaccines, experts say. Researchers will need to follow the variant to determine if it may reduce vaccine performance.
One of the mutations involves the spike protein, the piece of the virus that binds to receptors in our cells.
The vaccine immunizes people against the spike protein, which is why some infectious disease experts have expressed concern.
But the vaccine induces a broad immune response that will likely be able to recognize and respond to most variants.
“I think it’s highly unlikely that there’s going to be a variant that the vaccine completely doesn’t touch,” said Dr. Ellen F. Foxman, PhD, an immunologist and Yale Medicine Laboratory Medicine physician.
However, antibody treatment may not work as well if the virus has mutated, according to former FDA Commissioner Dr. Scott Gottlieb. Antibody treatment consists of using antibodies taken from people who had COVID-19 to treat new patients.
The new variant in the U.K.
The new strain identified in the United Kingdom, that’s now also swarming around the United States, is thought to be up to 70 percent more infectious than the original variant dominating outbreaks in the United Kingdom.
Known as the B.1.1.7 lineage, the strain has caused the majority of cases in southern EnglandTrusted Source and has been linked to an uptick in hospitalizations.
It’s also caused a spike in infections among people under 20.
According to the WHO, like the variant detected in South Africa, the strain in the United Kingdom has mutations in the spike protein.
A more transmissible variant will inevitably make the pandemic harder to control. Though the strain isn’t thought to cause a more severe disease, it could lead to more cases overall, along with more illness, hospitalizations, and deaths.
At this point, scientists believe the vaccines will be effective against the strain originally detected in the United Kingdom.
More research needed
Neuman said the variants seem to be spreading more rapidly, and that’s the one thing we can be certain of.
“When you read about scientists suggesting things the new strain might do, you are really just seeing how an early step in the scientific process works — we think, worry, spitball, imagine, hypothesize, and just wander through a series of ‘what if’s’ until we hit on a question that might be answered with an experiment,” Neuman said.
More research is needed to conclude if the spike protein mutations are what’s causing the strains to be more transmissible and if the mutations could impact vaccine efficacy.
Foxman suspects there may be other mechanisms at play.
Other contributing factors, such as the population’s habits and behavior, will need to be looked at, Foxman said.
Additionally, the virus is already transmitting faster because it’s more widespread than it was in March. When a greater percentage of the population is infected, viruses have an easier time spreading.
“The evidence is all based on epidemiology,” Foxman said. “It’s based on looking at the fact that this strain has spread more and been a higher proportion of cases than other genetic strains of the virus.”
We don’t yet have proof that the virus is biologically better at infecting our cells, Foxman added.
If the messenger RNA vaccines end up being less effective against variants, they can be quickly reworked to target new sequences.
“That’s a big advantage of that type of vaccine,” Foxman said, noting this scenario could introduce delays in the vaccine manufacturing and distribution processes.
All virus variants are prevented the same way
“SARS-CoV-2 remains about as preventable as a speeding ticket, no matter which variant we are talking about,” Neuman said.
Wearing a mask that’s tightly sealed around your face, washing your hands, and keeping a physical distance from others, especially in a crowded setting, can decrease your risk of developing COVID-19.
“Those same things work no matter what the virus is,” Foxman said.
There’s a lot to learn about the new variants. In the meantime, it’s best to stay vigilant as new strains arise.
The Bottom Line
Two new variants of the coronavirus have recently been detected in the United Kingdom and South Africa.
Due to mutations on the spike protein, the part of the virus that binds to our cells, both strains are thought to be more transmissible than previous strains.
More research is needed to determine if and how the mutations impact the virus’s behavior.
Experts continue to stress the importance of wearing a mask, practicing physical distancing, and washing our hands. These measures will likely protect against all variants.
