A pair of omicron subvariants are making inroads in the U.S. as BA.5 continues to decline, according to updated data from the Centers for Disease Control and Prevention.
At its peak in August, BA.5 was responsible for nearly 87% of new coronavirus cases. This week, the CDC estimates that it caused about 79% of infections.
While BA.5 remains dominant, other omicron subvariants are spreading. BA.4.6 and BF.7 – an offshoot of BA.5 – were responsible for over 13% and 4% of infections this week, respectively. BA.2.75 caused nearly 2% of infections.
These omicron subvariants are likely to continue to increase and contribute to a winter wave of COVID-19, says JT McCrone of Helix, a genetic sequencing company tracking COVID-19 variants.
Cartoons on the Coronavirus
“Given that we’ll see a relatively high number of cases, we could expect there to be new variants that crop up over the course of that wave,” McCrone says.
Cyrus Shahpar, the White House COVID-19 data director, said that more growth is expected from BA.4.6, BF.7 and BA.2.75 in the weeks ahead.
“Bottom line: These are all Omicron & we have a new bivalent dose that increases protection against all of them,” he tweeted.
The Biden administration has been pushing the updated COVID-19 shots that target the omicron variant ahead of the expected coronavirus surges in the fall and winter. The shots are designed to take on BA.4 and BA.5 as well as the original coronavirus strain, and federal health officials have said the shots should be better at preventing infections.
So far, 11.5 million people have taken the updated shot, which is about 4% of the population eligible to get it. According to a recent Kaiser Family Foundation poll, 32% percent of adults said they either have or plan to get the shot. Nearly half of Americans reported hearing little or nothing about the new shots.
It’s unclear if there will be enough uptake of the shot to prevent a significant number of infections in the fall and winter. The Biden administration has estimated the number of infected Americans could reach 100 million.
Meanwhile, the CDC announced on Wednesday that it will shift later this month from daily updates of COVID-19 cases and death numbers to a weekly update – much like the updates the agency provides for the flu.
“To allow for additional reporting flexibility, reduce the reporting burden on states and jurisdictions, and maximize surveillance resources, CDC is moving to a weekly reporting cadence for line level and aggregate case and death data,” the agency stated.
It’s just the latest rollback to federal efforts surrounding COVID-19. In recent months, the federal government suspended its free coronavirus testing program and ended quarantine recommendations for unvaccinated Americans who were exposed to the virus.