513 - Economic Impact of Pediatric Influenza Vaccination Coverage in the United States: A Modeling Analysis of Direct Medical Costs

Publication Number: 3494.513

Joaquin F. Mould-Quevedo, CSL Seqirus, Summit, NJ, United States; Van Nguyen, Na, Montreal, PQ, Canada

Background: Influenza remains a persistent public health concern among the pediatric population in the United States, contributing to substantial morbidity and, in severe cases, mortality each year. Despite the widespread availability of pediatric vaccines, low immunization rates continue to drive disease transmission and elevate the economic burden—primarily through increased direct medical costs associated with outpatient visits, hospitalizations, and intensive care.

Objective: This study employs advanced economic modeling to quantify the direct medical costs associated with suboptimal influenza vaccination coverage in the U.S. pediatric population (6 months – 17 years), evaluating the financial impact across varying immunization rate scenarios.

Design/Methods: We employed a dynamic, age-stratified transmission model to estimate influenza-associated costs under varying immunization rate scenarios (50%, 55%, 60%, and 70%). Two distinct flu seasons were modeled: low incidence (2011-2012) and high incidence (2017-2018). Cost outcomes included total influenza-related outpatient and inpatient expenditures. Vaccine effectiveness (VE) was averaged from CDC reports over the past ten seasons (58%). The analysis assumed universal quadrivalent influenza vaccination across all age groups.

Results: At the current U.S. influenza vaccination rate in pediatric population (~50%), total estimated influenza-associated medical costs during a high-incidence season amounted to US$251M for outpatient care and US$530M for inpatient care. In a low-incidence season, these costs were US$88M (outpatient) and US$170M (inpatient). Achieving the Healthy People 2030 target vaccination rate (70%) would yield significant economic savings: approximately US$125M during high-incidence seasons and US$79M during low-incidence seasons.

Conclusion(s): Improving pediatric influenza vaccination rates to recommended targets represents a highly cost-effective strategy, with the potential to significantly reduce direct medical expenditures, alleviate healthcare system burden, and support national public health goals.