EACH flu season, influenza quietly inflicts a heavy toll on U.S. adults aged 18 to 64, with hospitalizations and deaths mounting, especially among older adults and those with chronic conditions. A new study examining more than a decade of CDC data suggests that recommending recombinant influenza vaccine (RIV) over standard-dose inactivated influenza vaccine (SD-IIV) could substantially reduce this burden.
Despite a universal flu vaccine recommendation in the United States, vaccination coverage in working-age adults remains suboptimal. From 2012 to 2023 (excluding the 2020–2021 pandemic season), influenza led to a median of over 151,000 hospitalizations annually in this age group. Notably, adults aged 50–64 were three to five times more likely to be hospitalized or die from influenza than their 18–49-year-old counterparts.
The risk was particularly stark for adults with chronic conditions. Among the younger cohort (18–49), just 14% had chronic illnesses, yet they accounted for more than 28% of flu-related hospitalizations and deaths. These findings highlight a vulnerability often overlooked in vaccine strategy.
The analysis modeled a scenario in which RIV, known for its enhanced effectiveness in certain populations, replaced SD-IIV. The results were striking: up to 10,000 hospitalizations could have been prevented each flu season among working-age adults, especially those with comorbidities.
As the U.S. population continues to age and chronic disease becomes more prevalent earlier in life, tailoring flu vaccine recommendations to risk profiles may prove essential. The study reinforces the potential of RIV as a tool not only for individual protection but also for broader public health impact.
With flu season planning already underway in many health systems, this retrospective analysis adds weight to calls for more nuanced vaccine guidance, especially for adults who may not yet be considered high risk but face elevated odds of severe flu outcomes.
Reference: Torcel-Pagnon L et al. The Impact of Influenza on US Working-Age Adults: Exploring the Benefits of the Recombinant Influenza Vaccine. Clin Infect Dis. 2025:ciaf200.
