From the Guidelines
The RSV vaccine is recommended for pregnant women between 32-36 weeks gestation during September to January (RSV season) as a single dose to protect their newborns through passive antibody transfer, and for infants under 8 months born during or entering their first RSV season, with nirsevimab (Beyfortus) recommended as a single intramuscular dose (50mg for infants <5kg, 100mg for those ≥5kg) 1.
Key Recommendations
- Pregnant women should receive one dose of RSVpreF vaccine (Abrysvo) between 32-36 weeks gestation to protect their newborns through passive antibody transfer, with seasonal administration during September to January in most of the continental United States 1.
- For infants, nirsevimab (Beyfortus) is recommended as a single intramuscular dose (50mg for infants <5kg, 100mg for those ≥5kg) for all infants aged <8 months born during or entering their first RSV season, and for infants and children aged 8–19 months who are at increased risk for severe RSV disease and entering their second RSV season 1.
- High-risk infants with conditions like prematurity, chronic lung disease, or congenital heart disease should be prioritized for vaccination.
Rationale
- RSV is a leading cause of lower respiratory tract infections, especially dangerous for the elderly and young infants.
- The vaccines work by stimulating antibody production against the RSV F protein, preventing viral entry into cells.
- Protection lasts through one RSV season, with annual assessment needed for subsequent seasons.
Administration
- RSVpreF vaccine (Abrysvo) should be administered to pregnant persons during September–January in most of the continental United States to target vaccine to pregnant persons whose infants will be in their first months of life, when protection from maternal vaccination would be at its highest, during the RSV season 1.
- Nirsevimab (Beyfortus) can be administered in most of the continental United States from October through the end of March, based on pre–COVID-19 pandemic patterns 1.
From the Research
Guidelines for RSV Vaccine Administration
- The American Academy of Pediatrics recommends palivizumab for preterm infants born less than or equal to 32 weeks gestational age with or without bronchopulmonary dysplasia, those born between 33 and 35 weeks gestational age with additional risk factors, and infants and children with hemodynamically significant congenital heart disease 2.
- Palivizumab is administered intramuscularly, every month during the RSV season, usually 5 doses are required 3.
- The National Perinatal Association developed guidelines advocating IP use in all ≤32 wGA infants and 32-35 wGA infants with additional risk factors 4.
- Risk factor predictive models can identify infants who are at risk for RSVH and promote cost-effective use of palivizumab until new methods of RSV prevention become available 4.
Patient Selection
- Palivizumab has been shown to provide benefit for infants who were 32 to 35 weeks of gestation at birth 5.
- RSV-IGIV is contraindicated and palivizumab is not recommended for children with cyanotic congenital heart disease 5.
- The use of palivizumab for other high-risk children, including those with Down syndrome, cystic fibrosis, and haematological malignancy, is not well established and further research is warranted in these groups 6.
Administration and Efficacy
- Palivizumab is preferred for most high-risk children because of ease of administration (intramuscular), lack of interference with measles-mumps-rubella vaccine and varicella vaccine, and lack of complications associated with intravenous administration of human immune globulin products 5.
- Efficacy of palivizumab prophylaxis is documented by meta-analysis, and different economic analyses demonstrate cost-effectiveness of palivizumab for the most common indications during the first RSV season 2.
- A systematic review of postlicensure observational studies supports the recommended use of palivizumab for reducing RSV-associated hospitalization rates in premature infants born at gestational age < 33 weeks and in children with chronic lung and heart diseases 6.