National Advisory Committee on Immunization Statement on Seasonal Influenza Vaccines 2025–2026

Purpose of the Statement

NACI’s annual statement provides updated guidance on the use of seasonal influenza vaccines in Canada based on current evidence, epidemiology and authorized vaccine products. It supports both individual healthcare decisions and public health program planning.

Who Should Be Vaccinated

NACI recommends that seasonal influenza vaccine should be offered every year to everyone 6 months of age and older who does not have a contraindication. Immunization is particularly important for:

• People at high risk of serious influenza-related disease or hospitalization;
• People capable of transmitting influenza to high-risk individuals;
• Essential service providers (including healthcare workers);
• People whose occupational or recreational activities increase exposure risk to avian influenza A viruses.

Infants max 6 months are not currently eligible for licensed influenza vaccines; protection should be provided through vaccination of pregnant or breastfeeding contacts and caregivers.

Vaccine Schedule and Dosing

For the 2025–2026 season:

• Adults and children min 9 years: 1 dose annually;
• Children 6 months to max 9 years with no prior seasonal influenza vaccine history: 2 doses ≥4 weeks apart;
• Children 6 months to max 9 years with past seasonal vaccination history: 1 dose annually.

Types of Vaccines

A range of influenza vaccines are authorized in Canada, including inactivated and live attenuated formulations. Availability varies by age group and province/territory. NACI supports the use of any age-appropriate, authorized vaccine without strong preference for quadrivalent vs trivalent products in most cases.

Timing of Vaccination

Vaccination should be offered as soon as seasonal vaccines become available in the fall. Although earlier vaccination is preferable, vaccines may still be administered later in the season, including during ongoing influenza activity, since immunity can take time to develop.

Concurrent Vaccine Administration

NACI states that influenza vaccines may be given on the same day or at any time before or after other vaccines (including COVID-19 vaccines), using separate needles and sites where appropriate.

Why Annual Influenza Vaccination Matters

Influenza causes yearly outbreaks that can lead to hospitalization and death, especially in high-risk groups. Annual vaccination reduces the burden of disease and helps protect both individuals and the healthcare system. Vaccination will also help reduce strain on healthcare services when other respiratory viruses are circulating.