Coronavirus cases haven't been this low since last July — the latest CDC data shows about 30,000 daily cases. But that rate of decline is starting to plateau. These BA.2 cases are growing in that underbelly.
For the majority of Americans, experts say we don't need to worry as much as past waves.
An Omicron offshoot, scientifically known as Omicron sub-lineage BA.2, is creeping up in the U.S.
It's already caused a wave of increased cases in the U.K.
"We generally lag about three weeks or so behind the U.K. in the dynamics of what goes on with the outbreak," said Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases. "So if we are going to see an uptick, we should start seeing it within the next week or so."
CDC numbers show BA.2 now makes up roughly 35% of sequenced COVID cases in the U.S., which is up from 23% last week.
BA.2 cases are up from coast to coast. That portion is the largest in New England, where BA.2 now is just barely the dominant variant-making up 51% of new COVID cases there.
Scientists say tracking BA.2 trends in wastewater is key. They use wastewater because humans shed virus in our stool.
"Wastewater is really great because it's agnostic of behaviors around testing, around willingness, around costs, access, affordability," said Dr. Eric Feigl-Ding, epidemiologist and senior fellow at the Federation of American Scientists.
Wastewater testing shows more than a third of sites across the U.S. have detected increases of BA.2 and COVID cases in general in the past week.
"We've seen the wastewater going down for the last several weeks. And then just last week, the monitor data has taken an uptick," said Dr. Christopher Longhurst, Chief Medical Officer at UC San Diego Health.
BA.2 is 50% to 60% more transmissible than its Omicron parent strain. It does not appear to be more severe, especially in vaccinated and boosted individuals.
The World Health Organization says someone who has immunity from a previous Omicron infection should also have strong protection against infection with BA.2.
This comes as federal COVID funding is drying up.
The national Uninsured Program stops accepting new claims for testing at 11:59 pm Tuesday, pushing the cost on insurers, heath care providers, and patients.
"We've decided to take the position that we are not going to cut off access to testing," said Embry Health CEO Raymond Embry.