‘Stealth Omicron’ Subvariant Makes It To U.S.: What To Know

ACROSS AMERICA — A new subtype of the omicron coronavirus variant, known as BA.2, has been reported in 40 countries worldwide, including the United States, but it’s unclear yet if it’s more of a concern than its highly transmissible parent.

BA.2 doesn’t appear to be “a variant of concern,” the World Health Organization said this week, offering some potentially good news to a world worn out by a pandemic about to mark its second anniversary.

A variant within a variant, it’s sometimes called “stealth omicron” because some of the genetic traits aren’t as easily seen as the parent omicron variant, known as BA.1, in diagnostic tests.

And health experts aren’t sure what BA.2 portends, if it will fuel another surge of COVID-19 infections as the parent variant did, or if lockdowns and social distancing measures will be needed to control its spread.

“The BA. 2 descendant lineage, which differs from BA.1 in some of the mutations, including in the spike protein, is increasing in many countries,” the WHO wrote on its website. “Investigations into the characteristics of BA.2, including immune escape properties and virulence, should be prioritized independently (and comparatively) to BA.1.”

Here are things to know about the subvariant:

BA. 2 Is Dominant Strain In Denmark

The subvariant has been detected in Denmark, Britain and India, among other countries. BA.2 is widespread in Denmark and is now the dominant strain in the country of 6 million people, The Washington Post reported, but said that may be explained by the country’s robust program to sequence coronavirus genomes.

BA.2 accounts for 65 percent of new cases as the parent variant declines, Anders Fomsgaard, a virologist at Denmark’s State Serum Institute, told The Post in an email.

“We are not so concerned,” he wrote, “since we so far do not see major differences in age distribution, vaccination status, breakthrough infections and risk of hospitalization.

“Also, despite the high infection rate of BA.2, the numbers of hospitalizations [in] ICUs are decreasing,” he wrote.

Britain’s Health Security Agency said BA.1 is still dominant there, but on Friday designated BA.2 a “variant under investigation” due to increasing case numbers both domestically and internationally. As of Friday, 426 U.K. cases had been reported.

Half Of U.S. States See BA.2

Reports are constantly changing, but in the United States, 22 states reported 100 BA.2 cases as of the close of the business day Tuesday, Newsweek reported, citing the GISAID database.

Of the reported 11 BA.2 cases in California, two were in Santa Clara County, Patch confirmed.

It’s too soon to say if BA.2 will become a dominant coronavirus variant, Centers for Disease Control and Prevention spokeswoman Kristen Nordlund told The Post.

“Although the BA.2 lineage has recently increased in proportion in some countries, it remains a very low proportion of circulating viruses in the United States and globally,” she said. “Currently, there are insufficient data to determine whether the BA.2 lineage is more transmissible or has a fitness advantage over the BA.1 lineage. CDC continues to monitor variants that are circulating both domestically and internationally.”

Should You Worry?

That depends. Britain’s Health Security Agency said its early analyses suggest that BA.2 is more contagious than its parent, but it emphasized more analysis is needed.

James Musser, director of the Center for Molecular and Translational Human Infectious Diseases Research at Houston Methodist Hospital, told The Washington Post the subvariant is so new that health experts don’t know how quickly it might spread or how ill people might become.

Omicron, he told The Washington Post, “can clearly evade pre-existing immunity,” whether from vaccines or exposure to other variants of the coronavirus.

“What we don’t know yet is weather son-of-omicron does that better or worse than omicron,” Musser said. “So that’s an open question.”

Dr. Jacob Lemieux, an infectious disease specialist at Massachusetts General Hospital in Boston, told USA Today that he doesn’t think BA.2 will cause the same “degree of chaos and disruption, morbidity and mortality” as the omicron parent variant.

“I'm cautiously optimistic that we're going to continue to move to a better place and, hopefully, one where each new variant on the horizon isn't news,” he said.

It’s not unusual for viruses to mutate, often in harmless ways, and there’s no reason to believe BA.2 is any different, Tulane University School of Medicine virologist Robert Garry told The Post.

“Variants have come, variants have gone,” he said. “I don’t think there’s any reason to think this one is a whole lot worse than the current version of omicron.”

This article originally appeared on the Across America Patch