The World Health Organization is warning that a new variant of the coronavirus, named omicron, poses a high risk of infection around the globe.
While no cases of omicron had been detected in Pennsylvania or elsewhere in the United States as of Monday, local health experts are keeping a close watch on the variant and urging residents to get vaccinated against COVID-19.
“What’s notable about omicron is it has many features that we have seen in other variants of interest and variants of concern, and then it's got a whole bunch more,” Vaughn Cooper, an evolutionary microbiologist at the University of Pittsburgh, said in an interview.
First identified by researchers in South Africa, omicron has a high number of mutations that could make the virus more transmissible and potentially better at avoiding protective antibodies made by the vaccine and prior COVID-19 infection.
The Centers for Disease Control and Prevention has three classifications for variants (from least serious to most): variants of interest, variants of concern and variants of high consequence. The WHO on Friday labeled omicron a variant of concern, meaning it is one for which there is evidence of higher transmissibility, more severe disease or increased ability to evade immunity.
A viral variant emerges when a virus accumulates mutations and is then passed from one person to another. Viruses constantly mutate, and mutations happen during every viral infection, Mr. Cooper said. Most mutations aren’t dangerous, and mutated viruses rarely get passed from person to person.
“But when you have millions of infections per day, the probability that any given mutation gets transmitted goes up,” Mr. Cooper said.
Scientists are concerned about omicron because it has some of the same mutations as the highly transmissible delta variant, in addition to other mutations. Delta is responsible for more than 99% of the cases in Pennsylvania over the past several weeks, according to CDC data.
Cases of COVID-19 have risen in areas of South Africa affected by the new variant. It’s not clear, however, whether this increase is due to omicron or other factors.
Mr. Cooper said it’s too soon to know whether omicron is spread more easily or whether it causes worse symptoms. Some doctors in South Africa have reported mild COVID-19 in patients infected with the omicron variant, but most of these cases have been among people in their 20s and 30s — an age group that generally has milder COVID-19 symptoms.
“If it turns out to be more transmissible than delta, we've got our hands full,” Mr. Cooper said. “There's still a very large number of people who are unvaccinated or under-vaccinated.”
As of Sunday, Nov. 28, nearly 69% of Pennsylvanians age 18 and older were fully vaccinated, according to the CDC.
While there’s evidence that omicron may be better at dodging antibodies made by the COVID-19 vaccines, Mr. Cooper said that doesn’t mean our current vaccines will be useless against it. That’s because the vaccines spur different types of immune responses. Beyond antibodies, which provide the first line of defense against the virus, the vaccines also generate T cells that protect against severe symptoms. In other words, even if our antibodies are less effective against the new variant, other immune cells produced by the vaccine act as a backup to help protect us.
Mr. Cooper also cleared up a misconception about variants and vaccines. “Vaccines do not cause variants,” Mr. Cooper said. “In fact, they suppress them. It's the rampant number of infections that gives rise to variants.”
In a news conference on Monday, President Joe Biden called the new variant “cause for concern, but not cause for panic.” He said his administration is working on contingency plans if the existing vaccines don’t adequately protect against omicron.
“We do not yet believe that additional measures will be needed,” Mr. Biden said, adding that his team is talking to officials at Pfizer, Moderna and Johnson & Johnson about developing new vaccines or boosters if needed.
While the vaccines remain very effective at preventing death and hospitalization due to severe COVID-19, their ability to protect any kind of infection — with or without symptoms — appears to be decreasing somewhat. With that in mind, Mr. Cooper recommended that those who are eligible should get booster shots if they haven’t already.
Combined with boosters, masks, social distancing and better ventilation indoors remain effective ways to prevent the spread of COVID-19, Mr. Cooper said.
Maggi Barton, a spokeswoman for the Pennsylvania Department of Health, said the agency was performing genomic sequencing on patient samples, as well as collecting sequencing results from other labs, to detect potential variants in Pennsylvania of the SARS-CoV-2 virus, which causes COVID-19. Sequencing is a comprehensive test that spells out the entire genetic code of an organism, allowing scientists to understand how it might be changing and evolving.
“Science tells us that the more the COVID-19 virus multiplies, the more likely it will mutate and form new variants,” Ms. Barton said in an emailed statement.
She reiterated that getting vaccinated is the best mitigation strategy against current and future variants of the coronavirus. “Pennsylvanians who are vaccinated and eligible for a booster need to use this time to get their boosters,” she said. “Those who are not vaccinated, should get vaccinated.”
Appointments are available statewide for Pennsylvanians ages 5 and older for their primary series and 18 and older for their booster shot. Visit vaccines.gov to schedule an appointment.
First Published: November 30, 2021, 1:12 a.m.
