Flu Season Is Off to an Early Start, and Doctors Say Anyone Under 25 Should Get the Shot Now

Flu reached the West Coast about two and a half months earlier than normal this year, a timing not seen since 2010, according to Dr. Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. His advice for families is specific: “Especially those under 25 should be encouraged to get vaccinated earlier than usual, meaning now.”

That age cutoff takes in every child, every teenager and most college students. Osterholm made the comments in a Guardian article that The Manhattan Mercury published on Nov. 13, along with two other infectious disease experts.

Flu Showed Up Months Early on the West Coast

The Centers for Disease Control and Prevention still calls overall flu activity low nationally. Its weekly surveillance report for the week ending Oct. 24, published Oct. 30, says activity is rising in many areas and is higher than usual for this time of year. The agency estimates at least 16,000 flu hospitalizations so far this season.

The same report says one virus dominates: influenza A(H1N1)pdm09 accounted for 367 of 371 subtyped influenza A viruses that week, or 98.9%. It also recorded the first pediatric flu death of the 2026-27 season, an H1N1-associated case from week 40. Dr. Amesh Adalja of the Johns Hopkins Center for Health Security told the Mercury that no one has a fully certain explanation for the early start, though travel patterns may have played a role.

Why Doctors Single Out Anyone Under 25

The main strain is an H1N1 virus carrying a mutation called G155E, and the Mercury reported that it resembles H1N1 strains that circulated before 2009. Adalja said there is no evidence it makes people sicker, but early research suggests people under 25 have less immunity to it, and the virus may be better at evading protection from earlier infections and vaccines.

Dr. Alex Greninger, who heads the division of infectious disease diagnostics at the University of Washington, said a person’s own health matters more than the virus when it comes to severity. Recent heart disease or reduced heart and lung capacity, for example, can make flu much more dangerous. The Mercury also noted that one child’s death from flu has been reported this season, an elementary-aged child from outside the Denver metro area.

The CDC’s flu report counted 199 pediatric deaths for the 2025-26 season. The American Academy of Pediatrics said in August that historically about 85% of children who died from flu were unvaccinated, and that flu vaccination among children 6 months to 17 years stood at 49.4% through mid-May.

A Vaccine That Is Not a Perfect Match

The Mercury reported that the dominant variant emerged after this year’s vaccine formula was chosen, so the vaccine is a weaker match than in some years. Osterholm said it is less protective but still works, and compared it to a seatbelt: it protects against severe disease, hospitalization and death.

The Mercury article also says the vaccine’s makeup was settled months in advance, which is why the match can slip. Adalja said he hopes newer mRNA technology will eventually let makers pick strains closer to the start of the season.

When Protection Starts and What the AAP Recommends

Protection takes about two weeks to build, the Mercury reported, which is why the experts urged shots before the holidays. The AAP, the American Academy of Family Physicians, the American College of Obstetricians and Gynecologists and the Infectious Diseases Society of America each recommend a flu shot for everyone 6 months and older, including pregnant people in any trimester.

The AAP’s own 2026-27 recommendations, released Aug. 10, say any licensed vaccine that fits a child’s age and health is acceptable, and that the AAP does not prefer one product over another. The number of doses depends on a child’s age at the first dose and vaccination history. Dr. Kristina Bryant, a member of the AAP’s infectious diseases committee, said “the good news is flu vaccines have been thoroughly studied,” according to CIDRAP.

The CDC’s own flu vaccine page says everyone 6 months and older should get a flu vaccine every season, with rare exceptions. It says people with an egg allergy may receive any appropriate flu vaccine and that most vaccines can be given at the same visit.

Feeling unwell for a day or two after the shot is normal, Osterholm said, and much better than getting the flu. Parent Diaries has also covered when a child with a fever should stay home and a hospital visitor rule for children under 13 during respiratory virus season.

If Symptoms Start Anyway

At-home antigen tests are available for flu A, flu B and RSV, the Mercury reported, and knowing the strain helps doctors decide on antivirals such as Tamiflu or Xofluza, which can reduce severe illness, hospitalization and recovery time.

The AAP recommends antiviral treatment for children with suspected or confirmed flu who are hospitalized, who have severe or worsening illness, or who are at high risk of complications. For other children, outpatient treatment is an option if it starts within 48 hours of the first symptoms. Staying home when sick and washing hands remain the basics for limiting spread, the Mercury article says.

Flu seasons are hard to predict, and holiday travel often brings more infections. Greninger said a more typical season in January and February is still possible.

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This article was produced with AI assistance and edited for accuracy against the sources linked above.

Image: Epolk – CC BY-SA 4.0/Wikimedia Commons