A subvariant of omicron called BA.2 now accounts for nearly 35 percent of Covid-19 cases in the U.S., the Centers for Disease Control and Prevention reported Tuesday, a roughly 10 percent increase from the week before, when BA.2 was detected in 23 percent of U.S. cases.
The variant is most prevalent in the Northeast, accounting for more than 50 percent of Covid-19 cases in states like Connecticut, Maine, Massachusetts and New Hampshire.
But will the rise of BA.2 in the U.S. — widely anticipated after the omicron subvariant caused infection spikes in Europe over the past few weeks — have any measurable impact on the U.S. overall, particularly as Americans are just now getting back to normal routines?
Infectious disease experts remain steadfast in their prediction that the subvariant is unlikely to cause widespread severe illness or crush hospital resources as earlier variants have, even as BA.2 is estimated to be 30 percent more transmissible.
Dr. John Brooks, a medical epidemiologist and chief medical officer for the CDC’s Covid-19 response, said that while BA.2-related infections could rise, severe disease or deaths associated with the subvariant are unlikely to increase.
“Our data suggests that it’s going to keep growing,” Brooks said. “But we have a few things working in our favor,” starting with the recent omicron surge. Many people in the U.S. were infected with the omicron variant, he said, and are therefore likely to have high immunity from its subvariants, including BA.2.
“Prior infection with the original omicron appears to confer protection, not necessarily against infection but definitely against severe disease and death,” Brooks said.
Wastewater samples have also been touted as a way to monitor the spread of Covid-19, as the coronavirus is shed in sewage even before an infected person may feel sick enough to get tested.
Recent CDC wastewater data have suggested an increase in Covid-19, but Harvard University epidemiologist Bill Hanage said that may not accurately foretell a BA.2 surge that might result in severe illness.
It’s “worth noting that places in the U.S. that have lots and lots of BA.2 according to wastewater are not skyrocketing in the way they did BA.1 or even delta,” said Hanage, an associate professor of epidemiology at Harvard’s T.H. Chan School of Public Health.
Reinfection with BA.2 is rare, according to the CDC. Vaccinations, too, provide protection, Brooks added, but without the risks associated with infection from Covid-19.
Data collected by NBC News find that the U.S. is now averaging 32,884 Covid-19 cases per day. That’s down significantly from a height of nearly 810,000 cases-per-seven-day average in mid-January.
And on average, the number of average daily Covid-related deaths nationally has fallen below 1,000, a threshold that had not been met since just before the omicron variant was discovered in late November