Adult Vaccines in the US: More Shots, New Dynamics on the Horizon
The adult vaccine market is poised for explosive growth, with more than 100 product launches expected over the next 10 years. Are US clinicians ready?
Current pediatric vaccine rates: ~90%
Current adult vaccine rates: 20% to 62%
Current adult vaccine rates: 20% to 62%
Pediatric vs Adult Vaccines: Historic Bias
US vaccine policy historically prioritized children - the first FDA-approved vaccine was for diphtheria (pediatric), in the 1920s; the first adult vaccine approved by the FDA was for influenza in 1945.
Adult Vaccination Faces Persistent Barriers
Lower awareness and access; cost and insurance coverage, vaccine hesitancy. The result is vaccination rates far below pediatric rates, at a range of 20–62%.
The Present & Future of Adult Vaccines in the US
Context: Adult vaccine market is on the cusp of major expansion, driven by RNA tech, aging populations, focus on prevention, pandemic lessons. The major problem is that the US adult vaccine system is unprepared for future complexity and volume.
Vaccine Market Evolution, Growth
The vaccine market expected to triple in product volume over 10 yrs: in 2024 there are 35 vaccines for 13 diseases. By 2034, there will be an estimated 100–120 vaccines for 40 diseases.
Vaccine Schedule Compression, Forced Seasonality
A primary concern is that a surge in seasonal vaccines (eg, COVID, RSV) could compress adult vaccine scheduling. Ie, US vaccine volume may exceed 500M doses/year by by 2032, up from 200M today. Under forced seasonality, that would require administering 4.4M doses/day vs 1.1M doses/day (current flu season rate).
Readiness for Shift in Adult Vaccine Volume
Stakeholders in use, administration of adult vaccines underestimate the coming changes; PCPs, pharmacists, and others are unprepared. For example, 66.3% of HCPs don’t check vaccine status at every visit and more than half (53%) don’t administer vaccines at all.
No Standardization in the US for Adult Immunization
There is no cohesive national adult immunization strategy or interoperable tracking system (IIS). In fact, only some states mandate IIS participation;
eg, New Hampshire has none. The Advisory Committee for Immunization Practices to the CDC recommends Shared Clinical Decision-Making
(SCDM) for vaccines like RSV, but clinicians feel ill-equipped for nuanced conversations.
The "Battle of the Arm"
Research shows that adults are willing to get only 2 vaccines per visit and a total of 4 vaccines per year. The data show that US adults currently make <1 preventive care visit/yr. By 2032, adults aged 50+ may need 5.6 to 6.4 vaccines/year—doubling current expectations. Surveys find that 38% of adults feel overwhelmed by the anticipated vaccine volume.
Persistent Gaps in Vaccine Equity
Vaccine access disparities by race, income, insurance status persist with research showing that Black adults are 80% more likely to be hospitalized for influenza vs White adults; only 13% of Black adults vs 27% of White adults aged 65+ received the high-dose flu vaccine. No stakeholder feels responsible for addressing equity. Contrary to convention wisdom, the ACIP has no enforcement power.
Needed: Proactive, System-Level Solutions
The focus of current priorities needs to be on integrating new vaccines effectively into scheduling in order to improve health and economic outcomes. Moving forward, we must Eliminate access barriers; streamline reimbursement and operations; enhance record-keeping and coordination; and support informed consumer choice.
The Goal
Current pediatric vaccine rates: ~90%
Current adult vaccine rates: 20% to 62%
Current adult vaccine rates: 20% to 62%
Achieve adult vaccination rates on par with pediatric success
The COVID-19 pandemic accelerated an already emerging transformation in vaccine development. Driven by scientific and technologic breakthroughs, the adult vaccine market, in particular, is now on an historic trajectory, with more than 100 new vaccine product launches expected in the next decade, primarily focused on new indications.
The magnitude of the growth, however, will further complicate an already complex landscape. The adult vaccine sector struggles with low adoption rates, funding gaps, disparate racial and ethnic access, and delivery complexities.
A 2024 perspective piece, published in npj Vaccines, points to an early bias in the US toward pediatric vaccine development, driven in part, the authors note, by the surge in births during the post-WWII baby boom. Even before that, the first vaccine approved by the FDA was a pediatric shot against diphtheria, in 1920. The first adult vaccine, against influenza, came 2 decades later, in 1945.
The npj Vaccines perspective goes on to discuss the size of the adult vaccine expansion, with detail such as the expected jump in the number of vaccines available: 35 vaccines for 13 diseases in 2024 will mushroom to as many as 120 vaccines for 40 diseases; how the increasing number of shots will compress the current Advisory Committee for Immunization Practices vaccine schedule; and the authors' concern that the market is generally unprepared for the shift in volume.
In the short slide show above, we offer a topline look at the data from the full article, focusing on what primary care clinicians should be thinking about over the next several years.
References
Jones CH, Jenkins MP, Willams BA, Welch VL, True JM. Exploring the future adult vaccine landscape—crowded schedules and new dynamics. npj Vaccines. 2024;9:27. doiL10.1038/s41541-024-00809-z
