Omicron subvariants BQ.1 and BQ.1.1 — dubbed "escape variants" for their immune evasiveness — are steadily gaining prevalence in the U.S. and now account for more than 16 percent of all COVID-19 cases confirmed nationwide, CDC data shows.
Six latest updates:
1. Based on projections for the week ending Oct. 22, the CDC estimates that BQ.1 accounts for 9.4 percent of cases, while BA.1.1 accounts for 7.2 percent.
2. Early lab studies conducted in Asia suggest BQ.1 can evade immunity from vaccines or past infection but may not cause more severe illness, according to an Oct. 21 update from the European CDC.
3. As of Oct. 21, France had the highest BQ.1 prevalence of any European country at 19 percent, but this proportion is "not high enough for the variant to already have had a noticeable impact on the epidemiological situation," the European CDC said.
4. Due to a high level of variant diversity, experts say a potential uptick in COVID-19 cases this winter would likely be driven by several different lineages, rather than just one. Helix, a lab that helps the CDC track variants, said BQ.1, BQ.1.1 and BF.7 are on its watchlist because of their potential for immune escape.
"Now that a large majority of people have had COVID, there is a lot more pressure for SARS-CoV-2 to diversify, which explains the subvariant soup circulating right now," Helix told Becker's Oct. 24. "With this diversity, it's possible not just one lineage will take over like last winter, but several lineages with a specific mutation or combination of them will contribute to the expected winter uptick.
5. The threat of a winter COVID-19 surge comes amid warnings of a severe flu season and at a time when much of the general public has abandoned public health precautions.
"We're in a very challenging phase, to be very honest. I know most folks don't want to hear that," Dr. Syra Madad, an epidemiologist at NYC Health +and Hospitals in New York City, told The Washington Post. "Barely anybody is masking. We have very low vaccination rates for the updated boosters, as well as generally waning immunity. And to top it all off, we have these highly immune-evasive subvariants that are circulating."
6. President Joe Biden received his updated omicron COVID-19 booster Oct. 25, the same day the White House launched various efforts to promote omicron boosters ahead of a potential winter surge, according to ABC News.