Flu season in the U.S. typically runs from October through May, with activity usually peaking between December and March. According to the CDC, seasonal flu has caused anywhere from 9.4 million to 51 million illnesses each year over the past decade and a half.
While health experts often look to the Southern Hemisphere for clues about what may be ahead, a milder flu season there in 2026 doesn't necessarily mean the U.S. will experience the same. That's why getting vaccinated remains one of the most effective ways to reduce your risk of illness, hospitalization, and serious flu-related complications.
The 2026-27 flu vaccine was updated to better match the strains expected to circulate this season, including influenza A (H1N1), influenza A (H3N2), and influenza B/Victoria. Notably, the vaccine now targets an emerging H3N2 strain that was not well matched by last year's formulation.
How to Stay Healthy
Flu can be serious at any age, especially for children and older adults. To help protect your household, follow these tips:
- Get the flu vaccine. The CDC recommends annual flu vaccination for everyone ages 6 months and older to help protect against flu.
- Keep your distance. Avoid close contact with sick people and stay home when unwell. Cold, flu, and COVID-19 symptoms overlap, so testing can help identify the cause.
- Wash your hands often. Wash with soap and water or use alcohol-based hand sanitizer if unavailable.
- Cover your coughs and sneezes. Use a tissue or your elbow; discard used tissues immediately.
- Get enough sleep. Aim for seven to nine hours of sleep nightly to support your immune system.
- Stay active. Regular exercise supports your health and helps your body fight infections.
- Eat well and hydrated. Support your immune system with whole grains, lean proteins, fruits and vegetables, and stay hydrated to help your body function well.
Aim to get your flu shot by the end of October. Talk with your doctor if you have questions about vaccinations. Download the bulletin for more details.
