The U.S. is coming to a difficult COVID crossroads as the cold winter months approach and new immune-evasive variants of Omicron emerge, White House Chief Medical Advisor Anthony Fauci says.
While the situation is certainly different from last winter when Omicron dominated all other variants, a new “variant soup” of Omicron sublineages like XBB, BQ.1, and BQ.1.1 are gaining ground across the country, wiping out key tools used to protect immune-compromised people.
“We’re really at a point that may be a crossroads here. As we’re entering into the cooler months, we are starting to see the emergence of sublineage variants of Omicron,” Fauci said on the Conversations on Health Care radio show on Thursday.
For months, Fauci has been warning that a new, more immune-evasive variant would emerge over the winter. He previously sounded the alarm on the BQ.1 and BQ.1.1 sublineages of Omicron, because of their rapid infection rates and their apparent ability to evade antibody treatments.
Fauci has assured that healthy people with vaccinations, boosters, and/or a previous natural infection from a subvariant like BA.5 will be protected from the new sublineages. However, U.S. health officials fear antibody treatments like Evusheld—a pre-exposure prophylaxis treatment to prevent COVID-19 for severely immune-compromised people—will become ineffective in the face of these new variants.
Fauci also stressed in Thursday’s interview that the pandemic was far from over. The number of deaths from COVID, which still averages around 2,600 a week, remains far too high, Fauci emphasized, adding “we’re still in the middle of this—it is not over. Four hundred deaths per day is not an acceptable level.”
For the past two years, colder temperatures have brought seasonal upticks in COVID cases, which have then turned into massive waves of infection riding the emergence of highly transmissible new variants, like Alpha and Omicron.
This year “there is this soup of variants,” Tom Peacock, a virologist at Imperial College London, told the Atlantic. While no new variant has come out on top yet, Fauci and other experts are closely monitoring a pair of potentially troubling viral offshoots called BQ.1 and XBB, which may soon monopolize infections in certain parts of the world.
Both these new sublineages descended from Omicron: BQ.1 comes from BA.5, while XBB comes from two different BA.2 lineages recombined into one.
Experts in Asia are paying close attention to the XBB strain, which has taken a significant foothold in countries like Bangladesh and Singapore, and have called it one of the most immune-evasive variants yet.
Meanwhile in the U.S., the previous BA.5 variant still remains the most dominant strain, accounting for more than 49.6% of cases from Oct. 23 to Oct. 29, but the number of BQ.1 and BQ.1.1 cases has been steadily rising each week. BQ.1 and BQ.1.1 strains now represent 27% of all COVID infections combined, according to the Centers for Disease Control and Prevention’s Nowcast, when just a month ago the two strains only accounted for 1.7% of all cases.
BQ.1 and XBB are distinct enough from each other that they could end up co-circulating, Peacock says, but he notes that it is too early to say for sure.
Our holiday plans may be in jeopardy nonetheless, as Peacock grimly warns that we could soon get an unwelcome surprise—just as Omicron upended winter expectations last Thanksgiving.
November 4, 2022: The headline of this article was updated with the correct number of COVID deaths a week.
This story was originally featured on Fortune.com
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