Flu vaccines are updated for each season. The CDC’s current guidance recommends annual influenza vaccination for most people age 6 months and older, with the specific product and timing depending on age, health and availability.
At a glance
- Protection takes time to develop, so vaccination before flu spreads widely is useful.
- The flu shot and nasal-spray vaccine are not appropriate for exactly the same groups.
- A clinician or pharmacist can help choose a suitable product.
Why the vaccine changes
Influenza viruses change over time. Public-health agencies review surveillance information and update the seasonal vaccine composition to target viruses expected to circulate. The CDC maintains a season-specific page with the recommended composition and product information for 2026–27.
Who should consider vaccination
CDC guidance broadly recommends a flu vaccine every season for everyone 6 months and older, with uncommon exceptions. Age, pregnancy, allergies, prior vaccine reactions and certain medical conditions can affect which vaccine is appropriate.
The nasal-spray vaccine is an option for some nonpregnant people ages 2 through 49. It is not suitable for everyone in that age range. People who are pregnant should receive an age-appropriate injectable flu vaccine rather than the nasal spray, according to CDC guidance.
Timing and expectations
The body generally needs about two weeks after vaccination to build protection. Because flu activity varies by place and year, a vaccine given later in the season can still be useful when influenza viruses continue to circulate.
No vaccine prevents every infection, but vaccination is intended to reduce the risk of flu and its complications. Ask a healthcare professional about your circumstances, especially for children receiving their first flu vaccine, adults 65 and older, or anyone with a history of a severe allergic reaction.
A practical next step
Check the current CDC guidance, then contact a clinic, pharmacy or health department about availability. Bring questions about age restrictions, medical history and the differences among available products.
Sources
- CDC: 2026–27 flu season information
- CDC: Inactivated influenza vaccine information
- CDC: Nasal-spray flu vaccine
AskNovus links readers to the original official sources so you can review the underlying information directly.
This is an original AskNovus explanation based on the linked sources. It does not reproduce a publisher’s article. Featured image: CDC via Unsplash. This article is general information, not medical advice. Information may change after publication; check the official sources for the latest details.