RSV Prevention for Babies: Maternal Vaccine or Infant Antibody?

Jan 16, 2025

2 min read

Updated: Sep 25

Updated September 2026

RSV prevention for infants has changed quickly. Families now have two main pathways to protect babies from severe RSV: maternal vaccination during pregnancy or a long-acting RSV antibody given to the infant.

Maternal RSV vaccination

CDC recommends one dose of Pfizer’s Abrysvo during 32 through 36 weeks of pregnancy. In most of the continental U.S., the vaccine is given seasonally from September through January.

Infant RSV antibodies

Babies can instead receive a long-acting RSV monoclonal antibody. Current options include nirsevimab and clesrovimab. These are not vaccines—the antibodies themselves provide protection.

For most infants, an RSV antibody is recommended when the mother did not receive maternal RSV vaccine, maternal vaccination status is unknown, or the baby was born within 14 days of maternal vaccination. Most babies do not need both approaches.

Hawaiʻi is different

CDC specifically notes that tropical areas, including Hawaiʻi, can have different or less predictable RSV circulation patterns. Timing of infant antibody administration may therefore need to be adapted to local epidemiology rather than copied automatically from the October-through-March schedule used in much of the continental U.S.

Some older infants also qualify

Nirsevimab is recommended for selected children ages 8 through 19 months who are entering a second RSV season and have specific high-risk conditions. Clesrovimab is not recommended for the second RSV season.

The practical takeaway

The best RSV prevention plan depends on gestational timing, maternal vaccination, the baby’s age and risk factors, and local RSV circulation. The important change is that severe infant RSV is now something we can often prevent before illness starts.

— Nora Phillips, DNP, APRN Central Health | Wahiawa, Hawaiʻi

Source

CDC — RSV Immunization Guidance for Infants and Young Children. Updated August 18, 2025. https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/infants-young-children.html