In the United States, the influenza (flu) season lasts from October through May, with peak flu activity between December and March. Last winter, the United States faced an unprecedented, severe flu epidemic fueled by the highly mutated influenza A (H3N2) strain, known as the subclade K flu variant or “super flu.” The 2025-26 flu season was one of the worst in decades, and doctor visits for flu-like illness reached the highest levels seen in more than 25 years, according to data from the U.S. Centers for Disease Control and Prevention (CDC).
In response, ahead of the 2026-27 flu season, health officials updated all three virus components of the seasonal flu vaccine, the broadest overhaul in recent years. The change specifically targets the subclade K variant that emerged in 2025 and didn’t closely match the prior vaccine formulation. The updated vaccine now protects against influenza A (H1N1), influenza A (H3N2) and influenza B/Victoria lineage viruses.
This article previews the 2026-27 flu season and provides information about this year’s flu vaccine.
The 2026-27 Flu Season
While all three virus components included in seasonal flu vaccines have been updated for the 2026-27 season, the CDC has noted online that, due to legal uncertainties, its vaccination recommendations for the 2026-27 season remain consistent with those outlined in the July 2025 immunization schedule. Health experts emphasize that vaccination remains one of the best ways to reduce the risk of severe flu illness.
Separately, in August, the U.S. Food and Drug Administration approved the first mRNA flu vaccine for adults aged 50 and older. In a clinical trial of more than 40,000 adults in this age group, the vaccine was associated with approximately 26% fewer cases of laboratory-confirmed flu-like illness compared to a standard-dose flu vaccine.
Flu Vaccine FAQs
What Are the CDC’s Recommendations for Getting a Flu Vaccine for the 2026-27 Flu Season?
Carrying over from last season, the CDC recommends that everyone 6 months or older, with rare exceptions, get a flu vaccine. For those 65 years or older, the agency also recommends using higher-dose or adjuvanted flu vaccines rather than standard-dose unadjuvanted flu vaccines. However, if one of the preferentially recommended flu vaccines for people 65 and older is unavailable at the time of administration, the agency recommends that people in this age group get a standard-dose flu vaccine instead.
When Should I Get a Flu Vaccine?
It’s ideal for everyone who does not have a contraindication to be vaccinated in September or October. However, vaccination after October can still provide protection during the peak of flu season. The best time for you to be vaccinated may depend on factors such as your age or whether you’re pregnant.
What Viruses Will the 2026-27 Vaccines Protect Against?
There are several flu variants, and they can change and morph as the flu season progresses. The vaccines are created each flu season to combat the flu viruses that research indicates will be the most common.
All three virus components of the 2026-27 seasonal flu vaccine were updated. The change specifically targets an influenza A (H3N2) strain, known as subclade K, that emerged in 2025 and did not closely match the prior vaccine formulation. The updated vaccine protects against influenza A (H1N1), influenza A (H3N2) and influenza B/Victoria lineage viruses.
Although you may still catch the flu even after receiving a vaccine, immunization has been proven to reduce the severity of illness. The type of vaccine an individual needs depends on age and risk level. Speak to a doctor, pharmacist or other health care professional if you have questions about which flu shot is best for you.
What If I Have Egg Allergies?
Typically, flu vaccines are produced using an egg-based manufacturing process and contain a small amount of egg proteins. However, the 2026-27 flu vaccine is available in egg-free formulations. That said, the CDC noted that people with an egg allergy are not at “increased risk” of severe allergic reactions to egg-based flu vaccines, so it’s appropriate to receive any flu vaccine—egg-based or non-egg-based.
Summary
During this flu season, vaccination and other preventive measures can help minimize the risk of the flu for you and those around you. Other ways to support your health include staying home if you are sick, washing your hands frequently and maintaining a healthy diet.
Contact your physician with any questions regarding flu vaccination, and check out more information about flu season from the CDC. Its website will continue to be updated as the season progresses.
Provided to you by Hodge, Hart & Schleifer
This article is for informational purposes only and is not intended as medical advice. For further information, please consult a medical professional. © 2026 Zywave, Inc. All rights reserved.