Given the assumption that the circulating anti-SARS-CoV-2 IgG generated during either vaccination or infection might cross-react with human Hsps, we hypothesized that the healthy volunteers who got the anti-COVID-19 vaccine or the anti-SARS-CoV-2 IgG-positive participants have higher titers of anti-Hsp antibodies in their serum. This evidence concerns the gene HSP90B2P and infection.