The U.S. flu season is arriving earlier and running hotter than usual this year, federal health officials reported this week, with the season's first pediatric death now confirmed as activity climbs in most parts of the country.
The CDC's latest FluView report, covering the week ending Oct. 24, says seasonal flu activity remains low nationally but has been increasing steadily since late August — weeks ahead of the usual autumn ramp-up. Of 466 influenza viruses typed by public health labs that week, 456 were influenza A, and the overwhelming majority of those were the H1N1pdm09 strain rather than the H3N2 subtype that has dominated recent seasons.
The agency estimates at least 1 million illnesses, 16,000 hospitalizations and 900 deaths from flu so far this season across all age groups. The season's first pediatric death was reported to the CDC this week, though officials caution that child flu deaths are often confirmed weeks after they occur, so the count is preliminary and likely to rise.
A Season That Arrived Ahead of Schedule
CDC officials stressed that an early start doesn't necessarily forecast a severe season — prior years with early upticks have gone on to peak at both unusually high and unusually ordinary levels. But the agency's FluSight forecasting model projects a likely increase in both flu-related hospital admissions and emergency-room visits through at least mid-November, with new hospital admissions expected to range from roughly 4,800 to 23,200 in the week ending Nov. 14 alone.
Regional data show the percentage of clinical lab specimens testing positive for flu rose in eight of ten federal health regions compared with the prior week, with only the Northeast and the Pacific holding steady. Among influenza A viruses subtyped this season, 98.9% have been H1N1pdm09 — a descendant of the strain behind the 2009 pandemic, though CDC notes the subtype has caused routine seasonal epidemics for more than 15 years and is not considered pandemic-level now.
Health officials are using the early numbers to renew the annual push for vaccination, noting that flu shots are recommended for everyone six months and older and that prescription antivirals work best when started as soon as symptoms appear. People who haven't yet gotten a flu shot this season, the CDC said, should do so now rather than wait, since it typically takes about two weeks for protection to build after vaccination. The agency will update its national surveillance picture again next week as more states report data from the first full week of November.