The frequency of S-specific CD8 T cells was higher post-vaccination compared to post-infection, as was the CD8 \documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${T}_{EM}$$\end{document}TEM subset. This evidence concerns the gene CD8A and infection.