Although our immune response to vaccines decreases with age, vaccines remain crucial for reducing infection severity and risk in older adults. Adjusting vaccine components or administration can help offset this change.
TL;DR Our immune systems naturally get weaker with age, making it harder to fight off infections. Numerous accepted vaccination adjustments can compensate for these age-related changes.
As we get older, other health issues may seem more important than our annual flu shot. Vaccination, however, remains an important part of staying healthy as we age due to changes in the immune system. In fact, there are specific recommendations for the dosing and timing of vaccines in older people to help ensure that they remain just as effective.
Our immune systems become less responsive to vaccines and fighting infections as we age. The fancy scientific term for this is immunosenescence, meaning age-related declines in immune function. While the exact mechanisms underlying this decline are still being explored, early research shows that “inflammaging” (chronic low grade inflammation) and a decrease in the number/effectiveness of immune T and B cells are hallmarks of immunosenescence. Environmental and lifestyle factors such as smoking may contribute to chronic inflammation and accelerate this process.
Immunosenescence means that older adults are at a much higher risk of getting infected and having more severe infections. Older adults are also at higher risk of experiencing long term complications or death from infections. According to the CDC, 70-85% of seasonal flu-related deaths in the US are among adults over the age of 65. Similarly, compared to individuals under 65, adults 65+ accounted for over 75% of COVID-19 related deaths from 2020-2022.
There are already several established vaccination methods that account for immunosenescence in older adults. One strategy is to increase the dosage (meaning more antigen for the immune system to recognize), like the new FluzoneⓇ High-Dose vaccine. Research has shown that this new formulation generates a stronger immune response and offers better protection in older adults over 65.
Another approach is to increase the frequency or number of dosages. Regular booster shots of COVID-19 vaccines, for example, can significantly decrease the risk of hospitalization and death. More work is being done with other novel methods like adding adjuvants (ingredients that enhance vaccine responsiveness, like in Novartis’ MF59Ⓡ) or administering them in different routes, such as under the skin. These adjustments have already been instrumental to the development of new pneumococcal, RSV, and shingles vaccines, since infections from these diseases can be devastating to older adults.
Stay safe, stay smart.
Love,
Those Nerdy Girls.
Resources:
Disability Information and Access Line (DIAL): vaccine resources for individuals with disabilities
National Council on Aging: Which COVID Vaccine is Best for Seniors?
TNG: Why are there special flu shots for older adults?
