Herein, the reactivity of 170 putative SARS‐CoV‐2 S‐protein CD8+ and CD4+ T‐cell peptide epitopes in the same individuals prior to vaccination, after COVID‐19 vaccination, and again following subsequent natural infection was assayed using a high‐throughput reverse transcription‐quantitative PCR (HTS‐RT‐qPCR) assay. Here, CD4 is linked to COVID-19.