Vaccines for older individuals: barriers and solutions
December 20/2024
Increasing our investment in vaccines for older individuals is critical as we consider the needs of the aging population.
By Julie Perry
Many Ontarians can recall the yellow immunization cards either from their own childhood vaccination series or from their children’s, with check marks at 2, 4, 6, and 12 months of age. These milestones are so important that many new parents and nearly all healthcare providers know them by heart.
With age, the immunization landscape gets muddier. Protection offered by childhood vaccines can wane over time, and require boosting. Immunizations for things like influenza, shingles and pneumococcal pneumonia become even more important as these infections are more common in older adults. And an aging immune system may respond differently to an infection, making vaccine-derived protection essential for improving outcomes.
“Factors like frailty have a huge impact on the outcomes of common vaccine-preventable infections like influenza,” says Geriatrician and Professor of Geriatric Medicine at Dalhousie University Dr. Melissa Andrew. “It’s important that people realize that as they age, an infection may not kill them, but it may affect their ability to live independently even after they get better.”
Beyond booster doses for things like tetanus and yearly influenza and COVID-19 shots, Canada’s Immunization Guide recommends a shingles vaccine for adults 50 and over, and immunization against pneumococcal disease at 65. There are additional recommendations for people who have occupational exposures, travel, and have other medical conditions that may make them more vulnerable to poor outcomes from an infection, like cancer or immunosuppressive therapy.
Although most adults report being willing to receive these vaccinations, only 38.5% of adults (and 54.7% of adults 65 and older) had received a pneumococcal vaccine by 2023. Influenza vaccination coverage also fell short of coverage goals in 2023, with 70.2% of adults 65 years and older surveyed reporting being vaccinated.
Accessing vaccines can be a challenge for older adults, especially if they have mobility issues or are in long-term care. “It’s important that vaccination programs consider the needs of the population they are targeting,” says Dr. Christine Fahim, Scientist and Implementation Specialist at St. Michael’s Hospital.
Dr. Allison McGeer, an adult immunization expert, member of the Centre for Vaccine Preventable Diseases, Senior Clinician Scientist at Mount Sinai Hospital and Professor at the University of Toronto (U of T) points out that coverage may also be low because adults don’t know what vaccines they need, and when.
“Although 80-90% of adults surveyed say that they are up to date on vaccines, only about 10% are,” says McGeer. “We need a system that tells adults when they have to touch base for vaccines. And within that system we need a mechanism for both the adult and the provider to be able to quickly define who needs to get a vaccine. For children, we do this really well. In adults we’ve never tried to do this before.”
McGeer spoke recently at a webinar on Immunization in Older Adults hosted by The Centre Vaccine Preventable Diseases at U of T. She highlighted other systems-level barriers for adult vaccination in Canada including differing vaccine schedules from province-to-province, and emphasized the need for vaccine registries to help health care practitioners keep track of what vaccines a patient may be missing. “You can’t know where you’re going, unless you know where you are,” she pointed out.
At the end of the day, public funding for all recommended adult vaccines would go a long way towards increasing coverage, according to McGeer. “We’re willing to pay for treatment in adults. We’re willing to pay for prevention in kids. But we are not willing to pay for prevention in adults,” she said. Given that approximately one third of older adults will leave the hospital following an influenza infection with a functional decline in status than when they had been admitted, the case for increased investment in vaccination for older adults seems clear.