Adult Community-Acquired Pneumonia in the United States: The Economic Burden and the Potential Gains From Higher Vaccination Coverage

Background: Community acquired pneumonia (CAP) imposes a substantial health and economic burden in the United States, but current cost estimates vary widely by population and care setting. Objectives: To estimate annual direct healthcare costs associated with CAP among U.S. adults and evaluate pneumococcal vaccination mortality associations and alternative vaccination uptake scenarios among adults aged 65 years and older. Methods: Using outpatient treated pneumonia as a proxy for CAP, event-level expenditures from the 2023 Medical Expenditure Panel Survey were combined with published utilization estimates adjusted to 2023. We estimated annual costs for adults aged 18 and older across six service categories and expressed them in 2025 dollars. We used regression analysis to evaluate associations between changes in self-reported cumulative pneumococcal vaccination uptake and pneumonia mortality across 50 states and Washington, D.C., during 2021 2024. Two scenarios modeled mortality under maintenance of 2017 peak uptake and continuation of the preceding upward trend. Results: Estimated annual direct healthcare costs totaled $30.80 billion, including $26.74 billion for inpatient care, approximately 87% of total expenditures. A conservative scenario excluding repeat hospitalizations yielded $28.65 billion. The one year lagged change in vaccination uptake was inversely associated with pneumonia mortality (minus 0.45 deaths per 100,000 per percentage-point increase; p=0.0114). Compared with observed uptake, maintaining the 2017 peak of 74.7% yielded an estimated 1,462 fewer pneumonia deaths among adults aged 65 years and older during 2018 2024. Continuing the earlier annual increase of 0.84 percentage points yielded an estimated 2,855 fewer deaths over the same period. Conclusion: Adult CAP imposes substantial direct healthcare costs, driven primarily by hospitalizations. The observed vaccination mortality association and illustrative mortality projections support renewed efforts to increase pneumococcal vaccination uptake among older adults and monitor its population-level impact.