Ontario’s 2025-2026 RSV Prevention Programs

To: Health Care Professionals in Niagara
From: Clinical Services Division, Niagara Region Public Health
Reference: Ontario’s 2025-2026 RSV Prevention Programs
Date: September 23, 2025

The Ontario Ministry of Health has announced the Respiratory Syncytial Virus (RSV) immunization availability:

Vaccination for older adults can begin now; product can be ordered from Public Health or existing inventory can be used
The infant and high-risk children RSV program is anticipated to begin in early October. Communication will be shared when Beyfortus® becomes available to order.

This memo outlines updated eligibility and administration information to assist health care providers with planning and implementation. Office staff responsible for ordering vaccine and patient resources can refer to the “Office Staff Action” subheading.

Ontario’s Older Adult High-Risk RSV Prevention Program

There are two publicly funded vaccine products available to eligible high-risk older adults: Arexvy® (adjuvanted recombinant protein subunit) and Abrysvo® (bivalent recombinant protein subunit).

Eligibility

Starting this fall, Ontario’s older adult high-risk RSV prevention program is expanding to include all individuals aged 75 years and older. The high-risk eligibility criteria for publicly funded RSV vaccine remains the same for adults aged 60-74.

Health care providers who have patients 60 years of age and older that are not eligible to receive publicly funded RSV can provide these patients a prescription to purchase the vaccine privately.

If a patient previously received a dose of RSV vaccine at any time:

They are not eligible to receive another dose this season
- Booster doses are not currently recommended. Evidence supports the use of a single dose to prevent RSV disease for multi-year protection. The timing of subsequent doses is unknown; studies are ongoing to determine the duration of protection.
The Ontario Ministry of Health does not reimburse for publicly funded vaccines or vaccines purchased from the private market

Administration Guidelines for Arexvy® and Abrysvo®

Single 0.5 mL dose
As per the Ontario Ministry of Health guidance, RSV vaccine for high-risk older adults can be co-administered with COVID-19 and influenza vaccines as well as other recommended vaccines
Adult patients who have had an RSV infection, may be offered vaccination against RSV once they are clinically well. There is no specific interval that is recommended between RSV infection and RSV vaccination.
It is recommended that patients who have had a transplant (solid-organ or stem cell) wait 3-6 months post-transplant to receive an RSV vaccination. However, a minimum of 1-month post-transplant may be practiced at the discretion of the provider.

Ontario’s Infant and High-risk Children RSV Prevention Program

Two immunizing agents will be available to help prevent RSV for eligible individuals who are Ontario residents:

The monoclonal antibody (mAb) Beyfortus® for infants and high-risk children
The Abrysvo® vaccine for pregnant individuals (RSVpre-F) to protect their newborn

The National Advisory Committee on Immunization (NACI) preferentially recommends the use of Beyfortus® for infant protection due to its effectiveness, long-lasting protection, and positive safety profile. NACI will continue to monitor the evolving evidence and will update recommendations as needed.

Administration of both the vaccine to the pregnant individual and a monoclonal antibody to the infant is not recommended except under specific circumstances. See section “3. Beyfortus® and Abrysvo®” for details.

1. Beyfortus®

This year, Beyfortus® should be offered to eligible infants and high-risk children beginning early October and should continue to be administered throughout the RSV season (anticipated to end March 31, 2026):

Infants born April 1, 2025 or after and less than 8 months of age
Children up to 24 months of age who remain vulnerable to severe RSV disease through their second RSV season, following a discussion with a health care provider, including children who meet the high-risk criteria

Beyfortus® Administration Guidelines

Dosing is dependent on the age and weight of the infant/child at the time of administration
Do not split the 100 mg product of Beyfortus® into two 50 mg doses
- The manufacturer instructions indicate that Beyfortus® pre-filled syringes are manufactured to be administered as single dose
- Dose splitting could increase the risk of contamination and potential for vaccine administration errors
Beyfortus® can be given concurrently with both live and inactivated vaccines
Beyfortus® is generally not necessary or recommended for an infant who has had a confirmed RSV infection during the current RSV season. The additional benefit of administering Beyfortus® after recovery from RSV is unknown and expected to be low, as the risk of rehospitalization in the same season is very low. However, consideration may be given to severely immunocompromised infants who may not mount an adequate immune response to the RSV infection.

Infants born April 1, 2025 or later, who are currently less than 8 months of age:

Ideally administered at birth for newborns, or before the start of the RSV season
A single dose is administered based on the infant’s weight at the time of administration
- < 5 kg receive 50 mg. Do not split the 100 mg product.
- ≥ 5 kg receive 100 mg

Children at continued high-risk entering their second RSV season (over 8 months and up to 24 months of age):

Ideally administered before the start of the2025-2026 RSV season
< 10 kg receive 200 mg
- The health care provider can use their clinical discretion regarding administering a single dose of 100 mg, rather than 200 mg
≥ 10 kg receive 200 mg

Children who have received Beyfortus® and are undergoing cardiac surgery with cardiopulmonary bypass:

An additional dose should be administered as soon as the child is stable after surgery since the surgical procedure causes a drop in serum concentration
< 90 days after the first dose
- First season < 5 kg receive 50 mg (do not split the 100 mg product)
- First season ≥ 5 kg receive 100 mg
- Second season receive 200 mg
≥ 90 days after the first dose
- First season 50 mg
- Second season 100 mg

2. Abrysvo®

Pregnant persons between 32-36 weeks gestation who will deliver during the RSV season, following a discussion with a health care provider:

Do not administer RSV vaccine to a pregnant individual who has already received a dose of RSV vaccine during a past pregnancy.
- There is no data on either the efficacy or safety of additional doses of Abrysvo® given during subsequent pregnancies, and thus no recommendations regarding additional Abrysvo® doses can be made at this time.
- The newborn will be eligible to receive Beyfortus®, as the RSV vaccine was not provided during the current pregnancy
Health care providers caring for pregnant individuals should provide information on the RSV vaccine and monoclonal antibody to ensure informed consent.

Abrysvo® Administration Guidelines

Single 0.5 mL dose
Abrysvo® may be given on the same day as Tdap (tetanus, diphtheria, acellular pertussis), COVID-19, and influenza vaccines
Abrysvo® is the only RSV vaccine approved for pregnant individuals. Do not use Arexvy® (RSV vaccine for older high-risk adults) for pregnant individuals.

3. Beyfortus® and Abrysvo®

Administration of both the vaccine to the pregnant individual and a monoclonal antibody to the infant is not recommended except under specific circumstances:

Infants born less than 14 days after administration of Abrysvo® OR
Infants who meet the medical criteria for increased risk of severe RSV disease:
- All premature infants (i.e., <37 weeks gestation)

Infants who meet any of the high-risk criteria previously listed in this memo and outlined on the Ontario Ministry of Health RSV webpage (once available for the 2025-2026 RSV season)

Extended Expiry Dates for Abrysvo®

Be aware that the inner labels of the vials and prefilled syringes may have different expiry dates from the carton labels because the manufacturer has implemented shelf-life extensions for DIN: 02544040
Abrysvo® should be used by the expiry date printed on the carton, as the carton labels have been updated to reflect new expiry dates based on the extended drug product shelf –life and lot numbers

Office Staff Action

Please monitor Ordering Vaccinations for a new Seasonal Respiratory Products Order Form anticipated by the end of September. In the interim, to order RSV vaccine for high-risk older adults, use the high-risk order form currently posted on our website.
Access patient resources
- “Breathe Easy” poster
- Immunize Canada posters promoting older adult high-risk RSV vaccination
  - Do you provide care for a loved one living in a chronic care facility?
  - Who should get immunized against respiratory syncytial virus (RSV)?
- CARD resources to improve the vaccination experience
  - Your vaccine, your way! poster for children and adults
  - Comfort positions guide for parents/guardians/caregivers of young children

For More Information

Call 905-688-8248 or 1-888-505-6074 ext. 7396
Refer to our website for information on reporting adverse events after immunization. To report a side effect of Beyfortus® post-administration, see the Health Canada’s Side Effect Reporting Form. Suspected adverse events following administration of Beyfortus® are not reported to Public Health.