RSV Vaccine Frequency
The RSV vaccine for adults is administered as a single lifetime dose, not requiring annual or repeated vaccination. 1
Adult Vaccination Schedule
A single dose of RSV vaccine is currently recommended for eligible adults, with no booster doses required. 1 This represents a fundamental difference from annual influenza vaccination and reflects the sustained immune response generated by current RSV vaccines.
Optimal Timing of Administration
- The vaccine should preferably be administered between September and November, before or early in the RSV season, to maximize protection during peak transmission months. 2, 1
- While vaccination can occur at any time of year, pre-season administration ensures optimal antibody levels when exposure risk is highest. 2, 3
- In the Northern Hemisphere, RSV season typically runs from November through April, though timing may vary by geographic region. 1
Duration of Protection
The available evidence demonstrates sustained vaccine efficacy over multiple RSV seasons:
- RSVPreF3 (Arexvy) maintains efficacy for at least three seasons in adults aged ≥60 years. 2, 3
- RSVpreF (Abrysvo) maintains efficacy for at least two seasons in adults aged ≥60 years. 2, 3
These data support the current single-dose recommendation, though longer-term surveillance continues to evaluate whether future booster doses may eventually be needed. 4
Pediatric RSV Prevention: Different Approach
Pediatric RSV prevention uses a fundamentally different strategy than adult vaccination, relying on either maternal vaccination or monoclonal antibody administration rather than direct infant vaccination:
Maternal Vaccination
- Pregnant individuals receive a single dose of RSVpreF between weeks 28-36 of gestation (optimally 32-36 weeks) to protect infants from birth through 6 months of age. 1, 3
- This is administered seasonally (September through January in most continental US regions). 3
- There is currently no RSV vaccine approved for direct administration to neonates or infants. 5
Monoclonal Antibody (Palivizumab/Synagis)
- High-risk infants receive monthly intramuscular injections throughout the RSV season, administered every 28-30 days. 6
- This requires 5 monthly doses during a typical RSV season for continuous protection. 6
- Each injection provides approximately 1 month of protection, necessitating the monthly dosing schedule. 6
Important Clinical Considerations
Co-administration with Other Vaccines
- RSV vaccine can be co-administered with seasonal influenza vaccine at different injection sites. 2, 1, 3
- Some studies show numerically lower antibody titers for both RSV and influenza when co-administered, though clinical significance remains unknown. 2
- Data on co-administration with COVID-19 vaccines are lacking. 2
Common Pitfalls to Avoid
- Do not confuse the single-dose adult vaccine schedule with the monthly pediatric monoclonal antibody regimen - these are entirely different products with different dosing requirements. 1, 6
- Previous RSV infection does not confer long-lasting immunity and does not contraindicate vaccination - patients should still receive the vaccine even with prior RSV disease. 1
- Do not delay vaccination waiting for "perfect" timing - if RSV season has already begun, administer as soon as possible rather than waiting until the following year. 6
Declining Efficacy Considerations
While vaccine efficacy decreases over time (as expected for a virus characterized by short-term natural immunity), efficacy remains clinically meaningful over placebo through at least 2-3 seasons. 4 Current guidelines do not recommend booster doses, but ongoing surveillance may inform future recommendations as longer-term data accumulate. 4