11/26/2025
Flu Season Forecast
U.S. flu rates currently are low, but public health experts are bracing for a brutal season following unexpectedly early upticks in severe cases in Japan and the U.K., as well as rising case numbers in other European countries. Additional warning signs include a record 2025 flu season in Australia, where about 11 percent more cases have been reported than in 2024 (the most in the last two decades).
Influenza A and B are the two virus subtypes that primarily infect humans, with two A strains reported last year—H1N1 and H3N2, followed by B viruses later on. In the U.S., more than half of a small number of recently collected and analyzed samples of influenza A H3N2 strains was found to belong to a so-called K subclade, the new variant causing flu surges in many countries.
Current flu vaccines protect against multiple influenza A and B strains, but not the K variant, as the vaccine was developed before the new form emerged. Nonetheless, experts encourage people to get vaccinated because any reduction in the risk of severe flu is better than none. If you are high risk yourself or have vulnerable loved ones, including young babies who cannot get vaccinated until they are 6 months old, get vaccinated to protect yourself and others .