Aging is associated with a reduced magnitude of primary immune responses to vaccination and constriction of immune receptor repertoire diversity. Clinical trials demonstrate high efficacy of mRNA based SARS-CoV-2 vaccines in the elderly but concerns about virus variant escape have not been well addressed. Recently, we have conducted an in-depth analysis of humoral and cellular immunity against the early-pandemic virus strain as well as the P.1./Gamma, B.1.617/Delta and B.1.595 SARS-CoV-2 variants in adult and elderly mRNA vaccine recipients. As others have reported, robust immunity required the second dose of vaccine. Older vaccine recipients exhibited an expected 3–5x reduction (but not a complete loss) in neutralizing antibody titers against P.1./Gamma and B.1.595 that did not statistically differ from that measured in adults. Moreover, older vaccinees manifest robust cellular immunity against SARS-CoV-2, including to variants, that remained statistically comparable to the adult group. While the duration of these immune responses remains to be determined over longer periods of time, these results provide reasons for optimism regarding vaccine protection of older adults against SARS-CoV-2 variants. Experiments are currently in progress to determine cellular immunity in adult and older adult mRNA vaccine recipients to Omicron (B.1.1.529), the newest variant of concern. We will present results on T cell polyfunction and production of cytokines in response to Spike protein peptide pool from Omicron variant in a large cohort of convalescents and adult and elderly mRNA vaccine recipients.