Advertising Disclosure

Older adults should receive a high-dose or adjuvanted flu vaccine

Older immune systems respond less robustly to the standard vaccine

Updated:

Avatar photo
By:
Avatar photo

Mark Huffman
Reporter

Mark Huffman has covered consumer issues since 2004, with a special focus on protecting and empowering older adults. A former news correspondent for the Associated Press Radio Network, Westwood One, and ConsumerAffairs, Mark brings decades of journalistic experience to RetirementLiving.com. He is passionate about giving consumers a voice and helping them make informed decisions. Mark has also created educational content, including Senior Scam Alert, a video resource designed to help seniors recognize and avoid fraud. He holds a B.A. from the University of Kentucky and lives with his family in Richmond, Virginia.
cdc-unsplash

Photo by CDC on Unsplash

Key Insights

  • Researchers at the Cleveland Clinic have revealed new findings that could reshape how flu vaccines are designed, particularly the need to tailor strategies separately for younger and older adults.
  • The study suggests that immune responses to seasonal influenza vaccines vary significantly by age, prompting recommendations for age-specific vaccine formulations and dosing.
  • The work underscores a growing recognition that one-size-fits-all flu vaccine approaches may under-serve key populations—especially seniors and younger healthy adults alike.

At a time when seasonal influenza remains a major public health challenge, researchers at the Cleveland Clinic say their latest findings could usher in a more nuanced era for flu vaccine design, one that differentiates between younger and older adult populations, instead of relying solely on a universal strategy.

In a newly published, though not yet peer-reviewed, cohort study involving over 53,000 working-age employees, vaccinated individuals had a higher incidence of laboratory-confirmed influenza during the 2024-25 season compared with their unvaccinated peers—yielding a calculated vaccine effectiveness of –26.9%.

The authors and other experts caution that this outcome does not necessarily mean the vaccine caused increased infection—but rather that the vaccine, in that real-world scenario, failed to substantially prevent infections in that specific group.

Key take-aways

  1. Age matters: The study cohort was primarily working-age adults (health-care workers), with very few older adults or children represented. As a result, findings for older adults remain uncertain.
  2. Strain-match and formulation issues: As with all influenza vaccines, effectiveness depends on how well the selected vaccine strains match circulating viruses—the study reinforces that a poor match can dramatically reduce protection.
  3. Different needs for older adults: The Centers for Disease Control and Prevention (CDC) already recommends that people 65 and older receive a high-dose or adjuvanted flu vaccine, rather than a standard-dose one, because older immune systems respond less robustly.

What this means for older vs. younger adults

For younger healthy adults, the study suggests that standard formulations may not always deliver strong protection—especially in seasons with less-well-matched strains. That raises questions about whether alternative formulations (e.g., higher antigen load, adjuvants, newer platforms) should be considered even for this group.

For older adults, the implications are even more urgent. Their immune systems typically generate weaker responses and have a higher risk of severe outcomes. Thus, combining insights from this Cleveland Clinic study with existing recommendations suggests vaccine developers and public-health authorities should:

  • Consider age-tailored vaccine formulations, perhaps with different antigen contents or adjuvant systems for younger vs. older adults.
  • Evaluate alternate vaccine platforms (e.g., recombinant-protein, cell-based, mRNA) more actively in older populations.
  • Monitor not just infection incidence but also severity reduction, hospitalizations and deaths—particularly in seniors, where vaccine benefit may be more about preventing serious complications than preventing every infection.

The Cleveland Clinic is already running a new “Influenza Immunity Surveillance in Adults” study enrolling individuals aged 18-90 to examine how individual characteristics relate to vaccine responses.