Cost-Effectiveness Analysis of Older Adult Vaccination with the Bivalent Respiratory Syncytial Virus Prefusion F (RSVpreF) Vaccine in Mexico

Background/Objectives: Respiratory syncytial virus (RSV) causes substantial morbidity and mortality in older adults, and in Mexico’s rapidly growing older-adult population it may place increasing pressure on hospital-based care; however, Mexico-specific evidence to inform adult RSV immunization policy remains limited. This study estimated the long-term clinical and economic burden of medically attended RSV among adults aged 60–99 years in Mexico and evaluated the health impact and cost-effectiveness of a year-round RSVpreF vaccination program. Methods: A population-based Markov cohort model compared the RSVpreF vaccination with no vaccination in a hypothetical Mexican cohort aged 60–99 years over a lifetime horizon. Outcomes included RSV-related hospitalizations, emergency department (ED) and physician office (PO) encounters, in-hospital deaths, life-years (LYs), and quality-adjusted life-years (QALYs). Analyses were conducted from Mexican healthcare system and societal perspectives in 2025 Mexican pesos (MXN$) and US dollars (US$), with costs and outcomes discounted at 5% annually. One-way and probabilistic sensitivity analyses and scenario analyses assessed the robustness of the findings. Results: With 58% uptake, RSVpreF reduced hospitalizations by 187,825, ED encounters by 178,278, PO encounters by 465,976, and RSV-related deaths by 15,384. In the first 5 years, hospitalizations, ED encounters, and deaths declined by 31% each, and PO encounters by 14%. Over the lifetime horizon, vaccination generated an additional 96,227 discounted LYs and 71,526 discounted QALYs, while avoiding MXN$ 19,484 million (US$ 1061 million) in direct medical costs and MXN$ 3324 million (US$ 181 million) in indirect costs. Conclusions: Year-round RSVpreF vaccination in Mexico among adults aged 60–99 years could substantially reduce medically attended RSV cases and RSV-related mortality and is projected to be cost-effective, thereby supporting the adoption of preventive strategies to address the growing clinical and economic burden of RSV in Mexico’s aging population.