The Centers for Disease Control and Prevention on Friday revised downward its estimate of how much the omicron XBB.1.5 subvariant is circulating across the U.S., though it continues to spread at a faster pace than other versions of Covid-19.
XBB.1.5 made up 27.6% of sequenced Covid cases nationally for the week ending Jan. 7 compared with 18.3% for the week end Dec. 31. The CDC previously reported that XBB.1.5 made up about 41% of sequenced cases for the week ending Dec. 31, greater than another variant.
Although the agency has revised its estimate downward, XBB.1.5 stays the one omicron subvariant showing significant growth within the U.S. without delay. It’s second only to omicron BQ.1.1, which currently makes up 34% of sequenced Covid cases within the U.S.
XBB.1.5 makes up greater than 70% of sequenced cases within the northeastern U.S., which is usually a bellwether for the remainder of the country.
People walk past a COVID-19 testing site in Recent York, the US, on Dec. 7, 2022.
Michael Nagle | Xinhua News Agency | Getty Images
The World Health Organization has described XBB.1.5 as probably the most transmissible version of Covid yet. Scientists say XBB.1.5 has a mutation that makes it bind to human cells higher, which can make it higher at infecting people than other variants.
Dr. Ashish Jha, who heads the White House Covid taskforce, said in a series of Twitter posts Wednesday that the XBB.1.5 subvariant might be more immune evasive and can also be inherently more contagious since it binds more tightly to human cells.
Jha said It’s unclear whether XBB.1.5 is more dangerous than past variants. But Dr. Robert Califf, who heads the Food and Drug Administration, noted in a series of Twitter posts Wednesday that for now, cases are increasing with no evidence of increased severity of illness.
Jha warned that individuals who last had a Covid shot before September or who had an infection before July probably should not have strong protection against XBB.1.5. Seniors who will not be up thus far on their shots are increasingly vulnerable to serious illness, Jha said.
U.S. health officials must have more data soon on how much protection the omicron boosters provide against XBB.1.5., Jha said. Califf said the boosters should provide some protection against the subvariant based on studies that checked out other subvariants in the identical family, XBB and XBB.1.
“It is very likely that the present bivalent vaccines provide some protection against XBB, especially within the prevention of significant illness and death,” Califf wrote on Twitter.
Nonetheless, scientists at Columbia University, in a recent study, noted that variants within the XBB family pose a serious threat to the omicron boosters.
Weekly Covid cases have increased by about 16% to 470,699 over the past week, in line with CDC data. Average every day hospital admissions have increased 16% to greater than 6,500 over the past week, in line with the information. Weekly deaths have also increased 8% over the week prior to greater than 2,700.
