Third exposure to COVID-19 infection or vaccination differentially impacts T cell responses.

ABSTRACT:

Background

In 2021, the rapid rollout of two doses of SARS-CoV-2 vaccines reduced COVID-19 severity and mortality. However, further vaccine doses as a prime-boost schedule were limited, and lifting of public health restrictions by late 2021 frequently led to infection, rather than vaccine, as a third exposure.

Objective

To compare how the third exposure through mRNA booster or SARS-CoV-2 infection shapes humoral and cellular immunity following two vaccine doses.

Methods

We compared immune responses after the third exposure in healthy adults enrolled in the UCLH-Crick Legacy cohort study (NCT04750356) between those receiving ancestral spike-encoded mRNA booster (vaccine immunity, n = 38) or COVID-19 infection (hybrid immunity, n = 13) following two vaccine doses. Immun

SUBMITTER: Ahimbisibwe G 

PROVIDER: S-EPMC7618389 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature