Conventional flow cytometry analysis and multi-dimensional clustering analysis indicated unvaccinated asymptomatic participants had significantly fewer Wuhan-specific IL-2 secreting CD4<sup>+</sup> CD45RA<sup>+</sup> T cells and activated CD8<sup>+</sup> T cells than symptomatic participants, though these differences dissipated after vaccination.<h4>Conclusions</h4>Asymptomatic infection results in decreased antibody and T cell responses to further exposure to SARS-CoV-2 variants, compared to symptomatic infection. Here, CD4 is linked to infection.