What Is a Mutation and How Many Does Omicron COVID Variant Have?

The Omicron variant of COVID continues to spur governments and scientists into action this week, with booster shot programs being expanded.

In response to the potentially vaccine-resistant new variant, Pfizer is due to seek approval for COVID boosters in 16- and 17-year-olds in the U.S. while the U.K. is expanding its booster program to all adults.

Researchers have cautioned against panic over Omicron following some concern about the variant's many mutations.

What Is a COVID Mutation?

Throughout the pandemic, COVID mutations have referred to changes in the genes of SARS-CoV-2, the virus that causes the COVID-19 illness.

These genetic changes can cause the virus to act differently. For example, a virus may mutate in such a way that it spreads around people more easily, or more slowly. It may mutate in such a way that antibodies find it harder to latch onto it.

Whether or not mutations are of benefit to the virus is down to chance, experts have previously told Newsweek.

"Viruses mutate or change themselves at random, all the time," Dr. Francesca Beaudoin, interim chair of epidemiology at Brown University in Rhode Island, said earlier this year.

Most are inconsequential and fizzle out, she said, but some make the virus more effective.

This is not unique to COVID-19. Other viruses mutate as well, some more than others. Flu viruses do this so often that a new flu vaccine is recommended every year.

How Many Mutations Does Omicron Have?

As mentioned, scientists flagged Omicron due to the large amount of mutations it has.

Scientists in South Africa, Botswana, and Hong Kong have been widely praised within the scientific community for their work in sequencing the first cases of the variant and diligently sharing its information with the world on the GISAID virus network.

The World Health Organization's (WHO) technical briefing on the variant states there are 45 to 52 mutations in its genetic profile overall compared to a "reference strain."

But scientists have largely highlighted the 26 to 32 mutations relevant to Omicron's spike protein. The spike protein is what the virus uses to enter human cells and make us sick.

Laboratory studies are ongoing to figure out exactly what sort of differences these mutations make in terms of how Omicron infects people.

It's hard to tell exactly how infectious a virus is based solely on what mutations it has, Aris Katzourakis, an evolutionary biologist at the University of Oxford, told the journal Science. "But if we were looking out for mutations that do affect transmissibility, it's got all of them," he said.

Coronavirus illustration
A stock image shows an artist's illustration of the SARS-CoV-2 virus. It is normal for viruses to mutate, like the flu virus does. Gilnature/Getty