WHO’s first-ever position paper on RSV immunization provides guidance for two preventive measures: a maternal vaccine (RSVpreF) and a long-acting monoclonal antibody (nirsevimab). RSV is responsible for around 0.1 million deaths and 3.6 million hospital admissions each year in under-5 children; nearly half of these deaths occur in infants younger than six months, predominantly in low- and middle-income countries where supportive care is limited.

• Maternal vaccine (RSVpreF): Administered during the third trimester, thereby sending protective antibodies to the fetus. It received WHO prequalification in March 2025, allowing procurement by UN agencies.

• Monoclonal antibody (nirsevimab): Given as a single injection to newborns—ideally before hospital discharge or at the first postnatal visit—nirsevimab provides at least five months of protection, covering a typical RSV season. In areas with defined seasonality, infants up to 12 months can receive one dose before their first RSV season.

WHO advises every country to introduce either the maternal vaccine or nirsevimab, based on health system capacity, cost-effectiveness, and expected coverage. WHO highlights that these immunization strategies can significantly reduce RSV-related hospitalizations and deaths.

This position paper will guide policymakers, immunization program managers, and funding bodies on integrating RSV prevention into existing schedules.