globally, RSV causes millions of respiratory infections each year and is responsible for a large proportion of hospitalizations and deaths among children under five years, with the highest risk concentrated in infants under six months. The disease burden is especially pronounced in low- and middle-income regions, where limited access to healthcare and seasonal surges place substantial strain on pediatric services.Even though most of severe cases occur in healthy infants, prevention options have traditionally been restricted to high-risk groups.Recent advances in maternal vaccines and long-acting monoclonal antibodies have broadened the scope of RSV prevention,but questions remain regarding optimal timing,safety,duration of protection,and real-world implementation. Based on these challenges, there is a clear need for comprehensive research into integrated RSV immunoprevention strategies.
In november 2025, the Mexican Association of Pediatrics, in collaboration with a multidisciplinary national panel comprising pediatricians, neonatologists, infectious disease specialists, and obstetric experts, published (DOI: 10.1007/s12519-025-00997-1) a comprehensive position statement in World Journal of Pediatrics. The document synthesizes clinical trials,real-world effectiveness studies,and international policy experience to evaluate maternal RSV vaccination during pregnancy and passive immunization of infants using long-acting monoclonal antibodies. By systematically addressing efficacy, safety, optimal timing, and implementation challenges, the statement provides evidence-based guidance aimed at reducing severe RSV disease and hospitalization in infants across Latin America.
The consensus systematically reviewed evidence from randomized clinical trials, observational studies, and real-world program data to assess two principal RSV prevention strategies. First, maternal immunization with a prefusion F protein RSV vaccine demonstrated high efficacy in preventing severe RSV-related lower respiratory tract infections in infants during the first six months of life. Clinical trials reported protection exceeding 80% during the first three months, with sustained benefit up to six months, supported by efficient transplacental antibody transfer in late pregnancy.Large real-world studies further confirmed substantial reductions in infant hospitalizations and severe disease.
Second, the long-acting monoclonal antibody nirsevimab provided direct passive immunity to infants, achieving 75%-85% effectiveness against RSV hospitalizations across diverse populations, including healthy term and preterm infants. Evidence indicated that a single dose was sufficient to cover an entire RSV season, with favorable safety profiles and significant reductions in intensive care admissions.
Importantly, the analysis clarified that routine coadministration of maternal vaccination and monoclonal antibodies is generally unnecessary, except in specific circumstances where antibody transfer might potentially be compromised. Together, these findings support flexible, evidence-based prevention pathways that can be adapted to local epidemiology, healthcare capacity, and economic considerations.
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