T-cell response after first dose of BNT162b2 SARS-CoV-2 vaccine among healthcare workers with previous infection or cross-reactive immunity.

Here, we report that the first dose of BTN162b2 elicits a similar S-specific T-cell response in cases of either past infection or cross-reactive T cells, but lower in the rest of infection-naïve individuals and in convalescent HCWs who have lost detectable specific antibodies during follow-up.