Respiratory syncytial virus (RSV) immunization for infants

Respiratory syncytial virus (RSV) immunization protects infants from RSV, one of the most common respiratory viruses in infants and young children, infecting almost all children by the age of two years old. RSV can cause serious respiratory disease in infants and young children.

In New Brunswick, RSV immunization is provided free of charge from mid-October to the end of March for:

• All infants entering or born during their first RSV season (born as of April 1, 2026 and under eight months old)
  
• High risk infants who continue to be at risk of severe RSV disease entering their second RSV season (under 24 months old). This includes infants with certain medical conditions such as prematurity. Contact your health-care provider or local Public Health office to see if your child may be eligible.

Multiple immunizations can be given at the same time. This means earlier protection against multiple diseases and fewer appointments. Receiving multiple immunizations at the same time is safe and does not compromise the effectiveness of each vaccine.

Monoclonal antibodies (Beyfortus) protect infants from severe RSV illness for up to six months. Beyfortus has been shown to reduce hospital admission associated with RSV and lower medically attended RSV respiratory infection in healthy infants up to 80%.

Beyfortus provides immediate protection from RSV by supplying the infant with ready-made antibodies, a process known as passive immunity. This differs from vaccines which takes about two weeks to provide protection. 

The immunization should not be given if your child had a severe allergic reaction to a previous dose or to any ingredient in the product or its container.

There is no need to delay getting immunized because of a cold or other mild illness. However, if you have concerns, speak with your health-care provider.

Inform your immunization provider if your child has any health problems or allergies.

Reactions are generally mild and last one to two days. Common reactions may include soreness, redness and swelling where the immunization was given. Fever may also occur. For mild reactions, a cold compress at the injection site may reduce discomfort. Ask a health-care provider which medication is best to reduce fever.

With any immunization, there is an extremely rare possibility (less than one in a million people) of a life-threatening allergic reaction called anaphylaxis. For this reason, it is important to remain in the clinic for 15 minutes after receiving the immunization. Signs of this reaction may include rash, difficulty breathing or swelling of the throat, tongue or lips. This reaction can be treated. Seek immediate medical attention if you have left the vaccination site and develop serious symptoms.

If your child experiences unusual reactions to the immunization or you have any questions or concerns, please contact your primary care provider, pharmacy, Public Health office or Tele-Care (811).

In New Brunswick, the RSV season is from November 1 to the end of March. Beyfortus should be administered prior to or during the RSV season. The infant immunization program will begin mid- October.

Infants born/discharged before the RSV season:

• Immunization is provided by regional Public Health (Horizon, Vitalité) and some primary health care providers prior the start of the RSV season (e.g. October).

Infants born/discharged during the RSV season:

• Immunization is provided in obstetrics/newborn units or by midwives (home births) before the infant is discharged or afterwards through regional Public Health or primary health care providers.

Children who continue to be at risk of severe RSV infection in their second RSV season:

• Immunization is provided prior to the start of the RSV season, e.g. in October by regional Public Health (Horizon, Vitalité) and some primary health care providers.

The paper record of immunization provided when vaccinated will continue to be the official record. Keep your immunization record in a safe place.