Nirsevimab immunization effective and cost effective for preventing RSV related pediatric hospitalizations: JAMA

The research is based on a multisite observational study and real-life effectiveness analysis carried out among 19 hospitals for children located in 11 regions of Italy from October 2022 to March 2025. For decades, RSV was considered the most common pathogen responsible for causing lower respiratory infections among infants and thus imposing a tremendous seasonal impact on Europe's healthcare system. Although clinical trials confirmed high efficacy of nirsevimab, the study used Poisson regression models to assess the comparison of actual results and those predicted by models under the assumption of absence of vaccination. The study demonstrates that early implementation strategies help achieve maximum benefit for both patients and economy.

Key findings:

• In the 2024 to 2025 RSV season, there were documented 5,924 cases of RSV-induced admissions among children who were 18 years or less at the selected centers.
• In this case, the introduction of nirsevimab immunization campaign that started in October 2024 and ended in January 2025 resulted in a continuous decline in admissions than was predicted.
• Particularly, the intervention averted 6 to 151 admissions at each individual center.
• On a broader scale, the intervention prevented up to 83 to 1,162 admissions per 100,000 children.
• Moreover, from the point of view of the Italian National Health Service, the economic effects of the research were also impressive as in the majority of the centers involved ΔC was negative.
• This means that the amount of money that was saved because of the reduction of expensive hospitalizations exceeded greatly the amount spent on the acquisition and administration of nirsevimab vaccines.
• Specifically, per-center cost savings varied between −€10,924 ($12,562.60) and as high as −€266,954 ($306,997.10).
• This shows that immunization of children against RSV in most regions was not only financially beneficial but rather necessary for the public health services budgets.
• Cost-effectiveness ratios (CERs) were computed to further prove the economic feasibility of the immunization programs. Specifically, the ratio was found to be negative in some centers and to reach values like −€1,071 ($1,231.65) and even −€1,682 ($1,934.30).
• Nonetheless, the research team revealed that two centers experienced completely different outcomes due to late start or too narrow criteria for inclusion.
• Specifically, in those two cases ΔC turned out to be positive at values of €19,715 ($22,672.25) and €81,454 ($93,672.10).

The economic analysis of nirsevimab conducted in multiple centers in Italy proves beyond doubt that early and wide-spread immunization is the best means of dealing with the seasonal risk posed by RSV. According to this research, nirsevimab vaccination is not only effective but also economically feasible as it helps prevent a number of pediatric hospitalizations and save money. Although this strategy is very reliable, it can yield its maximum benefits only if the early implementation and low eligibility threshold are prioritized by healthcare specialists.

Reference:

Attaianese F, Carreras G, Trapani S, et al. Nirsevimab Immunization to Prevent Pediatric RSV Hospitalizations. JAMA Pediatr. Published online April 13, 2026. doi:10.1001/jamapediatrics.2026.0657