Diminished efficacy of influenza vaccines has fueled research and funding for a broadly protective vaccine. NIAID recently proposed at least 75% efficacy against symptomatic influenza as a key criterion for a universal vaccine. Our analyses demonstrate that universal vaccines with 75% efficacy would be highly impactful in reducing the epidemiological impacts of seasonal influenza at both the national and state levels. Reduced incidence and hospitalizations due to universal vaccine distribution would save $3.5 billion influenza-related direct medical costs per year. This economic benefit surpasses the current and proposed funding of $330 million combined toward the development of a universal influenza vaccine. Our results highlight that benefits of universal vaccine rollout justify the significant investment required for development.

Abstract

The efficacy of influenza vaccines, currently at 44%, is limited by the rapid antigenic evolution of the virus and a manufacturing process that can lead to vaccine mismatch. The National Institute of Allergy and Infectious Diseases (NIAID) recently identified the development of a universal influenza vaccine with an efficacy of at least 75% as a high scientific priority. The US Congress approved $130 million funding for the 2019 fiscal year to support the development of a universal vaccine, and another $1 billion over 5 y has been proposed in the Flu Vaccine Act. Using a model of influenza transmission, we evaluated the population-level impacts of universal influenza vaccines distributed according to empirical age-specific coverage at multiple scales in the United States. We estimate that replacing just 10% of typical seasonal vaccines with 75% efficacious universal vaccines would avert ∼5.3 million cases, 81,000 hospitalizations, and 6,300 influenza-related deaths per year. This would prevent over $1.1 billion in direct health care costs compared to a typical season, based on average data from the 2010–11 to 2018–19 seasons. A complete replacement of seasonal vaccines with universal vaccines is projected to prevent 17 million cases, 251,000 hospitalizations, 19,500 deaths, and $3.5 billion in direct health care costs. States with high per-hospitalization medical expenses along with a large proportion of elderly residents are expected to receive the maximum economic benefit. Replacing even a fraction of seasonal vaccines with universal vaccines justifies the substantial cost of vaccine development.