Vaccines for older adults

Abstract

The proportion of the global population aged 65 and older is rapidly increasing. Infections in this age group, most recently with SARS-CoV-2, cause substantial morbidity and mortality. Major improvements have been made in vaccines for older people, either through the addition of novel adjuvants—as in the new recombinant zoster vaccine and an adjuvanted influenza vaccine—or by increasing antigen concentration, as in influenza vaccines. In this article we review improvements in immunization for the three most important vaccine preventable diseases of aging. The recombinant zoster vaccine has an efficacy of 90% that is minimally affected by the age of the person being vaccinated and persists for more than four years. Increasing antigen dose or inclusion of adjuvant has improved the immunogenicity of influenza vaccines in older adults, although the relative effectiveness of the enhanced influenza vaccines and the durability of the immune response are the focus of ongoing clinical trials. Conjugate and polysaccharide pneumococcal vaccines have similar efficacy against invasive pneumococcal disease and pneumococcal pneumonia caused by vaccine serotypes in older adults. Their relative value varies by setting, depending on the prevalence of vaccine serotypes, largely related to conjugate vaccine coverage in children. Improved efficacy will increase public confidence and uptake of these vaccines. Co-administration of these vaccines is feasible and important for maximal uptake in older people. Development of new vaccine platforms has accelerated following the arrival of SARS-CoV-2, and will likely result in new vaccines against other pathogens in the future.

Efficacy of COVID-19 vaccine booster doses in older people

“…The clinical evidence accumulated so far would hence suggest that older people should be especially protected from SARS-CoV-2 infection. Nonetheless, physical measures such as wearing face mask, social distancing, hand hygiene and so forth are only partially effective for preventing viral infection and COVID-19-related complications [ 7 ], so that widespread administration of COVID-19 vaccines is now regarded as the most effective preventive strategy in older persons [ 8 ], as already proven for other infectious diseases such as influenza, meningococcal and pneumococcal diseases, hepatitis, herpes zoster, diphtheria and tetanus [ 9 ].…”

Vaccine efficacy and iron deficiency: an intertwined pair?

“…Although many factors have been shown to influence vaccine efficacy, 11 we have noted an unappreciated epidemiological overlap between lower vaccine efficacy and higher prevalence of iron deficiency and anaemia. For example, rotavirus vaccines and live attenuated influenza vaccines in infant populations in low-income and middle-income countries (LMICs), 12 , 13 hepatitis B vaccines in patients with chronic kidney disease or coeliac disease, 14 , 15 and influenza vaccines in older people, 16 , 17 all represent instances where lower efficacy has been reported and where iron deficiency is common.…”

Crohn’s and Colitis Canada’s 2021 Impact of COVID-19 and Inflammatory Bowel Disease in Canada: Seniors With IBD

“…On the one hand, similar results of lower efficacy among individuals above 80 years have been reported for pneumococcal vaccination ( 58 ). On the other hand, the herpes zoster vaccine efficacy is minimally affected by age ( 59 ). Additionally, individuals with IBD—particularly those treated with combination thiopurines and tumor necrosis antagonist therapy—have impaired immunologic response to vaccines, including against influenza ( 60 ).…”