Vaccine subtype and dose interval determine immunogenicity of primary series COVID-19 vaccines in older people.

ABSTRACT: Age is the strongest determinant of COVID-19 mortality, and over 2 billion people have received primary series vaccination with BNT162b2 (mRNA) or ChAdOx1 (adenoviral vector). However, the profile of sustained vaccine immunogenicity in older people is unknown. Here, we determine spike-specific humoral and cellular immunity to 8 months following BNT162b2 or ChAdOx1 in 245 people aged 80-98 years. Vaccines are strongly immunogenic, with antibodies retained in every donor, while titers fall to 23%-26% from peak. Peak immunity develops rapidly with standard interval BNT162b2, although antibody titers are enhanced 3.7-fold with extended interval. Neutralization of ancestral variants is superior following BNT162b2, while neutralization of Omicron is broadly negative. Conversely, cellular respons

SUBMITTER: Parry H 

PROVIDER: S-EPMC9404227 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature