Maheshi N Ramasamy et al.
Lancet (London, England), 396(10267), 1979-1993 (2020-11-23)
Older adults (aged ≥70 years) are at increased risk of severe disease and death if they develop COVID-19 and are therefore a priority for immunisation should an efficacious vaccine be developed. Immunogenicity of vaccines is often worse in older adults