More U.S. Babies Are Entering RSV Season Protected: How Maternal Vaccination and Infant Antibodies Are Working in 2025-2026

More U.S. babies are entering RSV season with some protection already in place. In CDC’s March 25, 2026 RSVVaxView update, 65.1% of infants born since April 1, 2025 were reported protected through either maternal immunization only or an infant monoclonal antibody. CDC’s December 2025 season outlook also said infant uptake appeared higher than it was at the same point last season, and that RSV prevention products are expected to keep lowering infant hospitalizations in 2025-2026. ([cdc.gov](https://www.cdc.gov/rsvvaxview/dashboard/index.html))

What the new CDC numbers mean

That 65.1% figure is not all one type of protection. CDC said 9.4% of infants were reported protected through maternal immunization only, while 55.7% were reported to have received an infant monoclonal antibody. Another 9.1% of parents said they definitely intended to get the infant product. These are preliminary, survey-based estimates, so they are best read as a national snapshot of progress rather than a final count. ([cdc.gov](https://www.cdc.gov/rsvvaxview/dashboard/index.html))

For families, the big takeaway is simple: more babies are reaching their first RSV season with a prevention plan already in place. CDC has also said recommendations for infant RSV prevention have not changed from last season, even though a second infant monoclonal antibody option became available in 2025. ([cdc.gov](https://www.cdc.gov/cfa-qualitative-assessments/php/data-research/season-outlook25-26-dec-update.html))

Two ways babies can be protected

The first path is maternal RSV vaccination. In most of the continental United States, CDC recommends a single dose of Pfizer’s Abrysvo during weeks 32 through 36 of pregnancy, generally from September through January. The vaccine helps the pregnant person make antibodies, and those antibodies cross the placenta to protect the baby after birth. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/pregnant-people.html))

The second path is an infant monoclonal antibody given directly to the baby. CDC says infant RSV antibodies are recommended during October through March in most of the U.S., ideally shortly before the season starts or within a baby’s first week of life if the baby is born during the season. These products are not vaccines; they do not train the immune system the way a vaccine does. Instead, they give the baby ready-made antibodies for immediate protection. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/infants-young-children.html))

Families may now hear two infant product names: nirsevimab and clesrovimab. The FDA approved clesrovimab, sold as Enflonsia, on June 9, 2025 for babies born during or entering their first RSV season. In practice, which monoclonal antibody a family is offered can depend on what a hospital or clinic is using, along with local access and reimbursement logistics. ([fda.gov](https://www.fda.gov/drugs/drug-approvals-and-databases/drug-trials-snapshots-enflonsia))

The core rule: most babies need one route, not both

CDC’s guidance is clear on the practical point many parents ask about: most infants do not need both maternal vaccination and an infant monoclonal antibody. For most healthy babies entering a first RSV season, the plan is either maternal vaccination late in pregnancy or one infant monoclonal antibody dose after birth or at season start. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/pregnant-people.html))

When a baby may still need the infant product

There are several important exceptions. CDC recommends an infant monoclonal antibody if the mother was not vaccinated during the current pregnancy, if maternal vaccination status is unknown, or if the baby was born within 14 days after maternal RSV vaccination. That last point matters because the baby may not have had enough time in utero to receive adequate transferred antibodies. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/infants-young-children.html))

A maternal RSV shot from a previous pregnancy does not count for a new baby in the current pregnancy. CDC says revaccination is not currently recommended in later pregnancies, so if the mother was vaccinated in an earlier pregnancy but not the current one, the new infant should receive the monoclonal antibody during the usual October-through-March window. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/pregnant-people.html))

CDC and Immunize.org also describe rarer situations where a baby may still be considered for an infant monoclonal antibody even if maternal vaccination happened at least 14 days before delivery. These include cases where the mother may not have mounted a strong immune response, where antibody transfer across the placenta may have been reduced, where the infant may have lost maternal antibodies after procedures such as cardiopulmonary bypass or ECMO, or where the infant has especially high risk for severe RSV disease. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/infants-young-children.html))

Why this matters: the latest real-world evidence

A January 2026 JAMA Pediatrics study helps explain why these prevention options matter. Researchers used population-based surveillance and a test-negative case-control design at seven U.S. pediatric medical centers, enrolling 5,029 children younger than 2 years from October 1, 2024 through April 30, 2025. Among the youngest infants, maternal RSV vaccination was associated with about 70% effectiveness against RSV hospitalization, while nirsevimab was associated with about 81% effectiveness against RSV hospitalization. The study also estimated that RSV hospitalization rates in newborns and infants ages 0 to 11 months fell by roughly 41% to 51% during 2024-2025 compared with earlier comparison periods. ([jamanetwork.com](https://jamanetwork.com/journals/jamapediatrics/article-abstract/2843213))

Those numbers are encouraging, but they are not a head-to-head randomized contest between the two approaches. The study was observational, not randomized, and its population-level impact estimates came from before-and-after and counterfactual comparisons. That means the findings support real-world benefit, but they do not prove that one strategy is universally better for every baby or that the drop in hospitalizations came only from these products. ([jamanetwork.com](https://jamanetwork.com/journals/jamapediatrics/article-abstract/2843213))

What parents should do now

If you are pregnant or expecting a baby soon, ask about your RSV plan before delivery if possible. If the plan is maternal vaccination, confirm whether it was given during the current pregnancy and whether the baby will be born at least 14 days later. If the plan is an infant monoclonal antibody, ask whether it will be given during the birth hospitalization, before the RSV season starts, or at an early outpatient visit. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/pregnant-people.html))

It is also worth asking the obstetric team, pediatrician, birthing hospital, or newborn nursery which infant product they use, whether the mother’s vaccination record can be verified before discharge, and whether access, reimbursement, or follow-up logistics could affect timing. CDC’s infant guidance says hospitals and health systems have flexibility to improve access, including around reimbursement and local supply considerations. ([cdc.gov](https://www.cdc.gov/rsv/hcp/vaccine-clinical-guidance/infants-young-children.html))

What this means for readers: more U.S. babies are starting RSV season protected than last year, and for most families the decision is not between doing everything at once. It is about making sure one appropriate protection route is in place, at the right time, before RSV exposure begins. ([cdc.gov](https://www.cdc.gov/rsvvaxview/dashboard/index.html))

Sources

This article is for general informational purposes only and is not medical advice. Research findings can be early, limited, or subject to change as new evidence emerges. For personal guidance, diagnosis, or treatment, consult a licensed clinician. For current outbreak or public health guidance, follow your local health department, the CDC, or another relevant public health authority.