Flu Surges Nationwide, With 32 States and Jurisdictions at High Activity

Flu is spreading quickly across the United States, and new data from the Centers for Disease Control and Prevention show a sharp increase in hospitalizations, CBS News and NBC News reported on Tuesday.

For the week ending Dec. 20, flu activity was “high” or “very high” in 32 states and jurisdictions, up from 17 the week before, the CDC reported. The agency estimated at least 7.5 million illnesses this season, about 3,100 deaths, and, according to CBS News, at least 81,000 hospitalizations. NBC News reported that weekly hospitalizations nearly doubled, from 9,944 to 19,053. New states reporting high levels included California, Nevada, Missouri, Arkansas, Alabama and Florida, while New York, New Jersey, South Carolina, Louisiana and Colorado were already at the “very high” level.

The New York State Department of Health recorded about 71,000 cases in the week ending Dec. 20, the most in a single week since it began tracking in 2004, with more than 3,600 hospitalizations, CBS News reported. Boston announced a 114 percent increase in recent cases, mostly among children.

The CDC’s lab data point to a new subtype. Of 2,086 specimens that tested positive for flu from Dec. 13 to Dec. 20, 2,029 were influenza A, and of 1,627 that were subtyped, 1,493, or nearly 92 percent, were H3N2, CBS News reported. Jesse Bloom, a scientist at the Fred Hutchinson Cancer Center who studies viral evolution, told CBS News that the virus has changed enough to be harder for immune systems to recognize and that the strain is known for causing tougher seasons, especially for seniors. Richard Webby of a World Health Organization collaborating center on influenza said experts expect an “H3N2 mismatch” with the vaccine but a good match to H1N1 and flu B.

About 130 million doses of flu vaccine have been administered nationwide, the CDC said, according to CBS News. Early data from the United Kingdom suggest the vaccines are still helping prevent severe illness, especially in children, CBS News reported. “It’s not going to eliminate their chance of getting infected, but it does mitigate their risk,” Bloom said.

Doctors expect the surge to continue. “It’s not anywhere close to peaking or leveling off,” Dr. Daniel Kuritzkes of Mass General Brigham told NBC News, which reported that illnesses may not level off until the end of January or February. Dr. Jennifer Goebel of South Shore University Hospital said, “I don’t remember seeing flu cases this early and in this many numbers.” The CDC figures are surveillance estimates drawn from reporting health departments and labs rather than a controlled study.