The Omicron subvariant XBB.1.5 is still gaining ground within the United States, accounting for at least 43% of sequenced cases from the last week, according to estimates from the Centers for Disease Control and Prevention (CDC).

The big picture: The XBB.1.5 COVID subvariant — nicknamed the “Kraken” variant — is representing more and more cases, and experts are questioning the variant’s severity as real-world data emerges.

XBB 1.5 cases subvariant rise

Details: The XBB 1.5 variant accounted for 43% of sequenced cases for the week ending Jan. 14 — up from 30.4% the week before, according to the CDC’s estimates.

• New York City health officials said the subvariant now accounts for close to 73% of cases sequenced in New York, per NBC New York.
• Hawaii’s Department of Health said the subvariant was recently discovered in wastewater, Hawaii News Now reports.
• Houston health officials said XBB.1.5 is likely accounting for the city’s rise in COVID-19 cases, too.

Flashback: The CDC said at the end of December that the XBB.1.5 strain was responsible for 40.5% of confirmed U.S. cases for the week ending on Dec. 31, 2022, Axios reported.

• But one week later, the CDC’s estimates changed to reflect that the XBB.1.5 variant made up 18.3% of cases for the week ending on Dec. 31, 2022, and 27.6% of sequenced cases for the week ending on Jan. 7.

XBB 1.5 variant: Severity and symptoms

Details: The World Health Organization said in a risk assessment earlier this week that the omicron XBB.1.5 variant — which it called one of the “the most antibody-resistant variants” — doesn’t have any mutations that make people sicker compared to previous variants.

• But the WHO said it doesn’t have any real-world data on how the variant is actually affecting people, so the full severity of the variant and its symptoms can’t be fully determined, CNBC reports.

What they’re saying: Dr. Ashish Jha, head of the White House COVID Task Force, said earlier this week that “your protection against an XBB.1.5. infection is not that great” if you had a COVID-19 infection before July 2022 or your last vaccine was before the recent bivalent update in September.

• “We will soon have more data on how well vaccines neutralize XBB.1.5,” Jha tweeted. “But right now, for folks without a very recent infection or a bivalent vaccine, you likely have very little protection against infection.”

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