As coronavirus cases rise in parts of Europe and Asia, scientists worry that an extra-contagious version of the omicron variant might soon push cases up in the United States too.
Experts are also keeping their eyes on another mutant: a rare delta-omicron hybrid that they said doesn’t pose much of a threat right now but shows how wily the coronavirus can be.
The latest data from the Centers for Disease Control and Prevention shows the share caused by BA.2 is up significantly.
It’s something medical experts in Connecticut are keeping an eye on.
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“I think it's pretty established now that the BA.2 is more transmissible,” Dr. Onyema Ogbuagu, a Yale School of Medicine associate professor and infectious diseases specialist, said.
Ogbuagu said BA.2 doesn't appear to cause more severe disease and that in the next few weeks we'll see the subvariant become the dominant strain in the country.
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There is at least a potential for it to cause a secondary wave of cases, Ogbuagu said, and the reported numbers might not reflect what's happening in communities.
“There's a lot of home tests available, and I think some of those home tests are not really making it to our reporting databases,” he said.
After about two months of falling COVID-19 cases, pandemic restrictions have been lifted across the U.S. Many people are taking off their masks and returning to indoor spaces like restaurants and theaters.
The CDC recently acknowledged it's increasingly likely that COVID will never truly go away at that it will probably become a seasonal virus.
“The predictions certainly are that at some point we're going to shift from the epidemic phase to the endemic phase,” Ogbuagu said.
He believes the COVID-19 vaccine will eventually take on an annual role, similar to the flu shot.
But immunity begins to wane after three to four months, which could mean those more vulnerable could see an additional annual booster, Ogbuagu said.
Prevention against disease is the best option because immunity through vaccine beats natural immunity after infection and there's still much to learn when it comes to the long-term effects some deal with after becoming infected, he added.
“We're only beginning to learn about long COVID, which are some of the either persistent symptoms that don't go away or that worsen over time or in some cases new symptoms that start,” Ogbuagu said.
One reason the variant has gained ground, scientists say, is that it’s about 30% more contagious than the original omicron. In rare cases, research shows it can sicken people even if they’ve already had an omicron infection — although it doesn’t seem to cause more severe disease.
Vaccines appear just as effective against both types of omicron, but breakthrough infections are possible.
Experts point out that vaccination rates are lower in the U.S. than the U.K. About 74% of those 12 and older are fully vaccinated in the U.S, compared with 86% in the U.K.
