The impact of Foot-and-Mouth Disease Virus (FMDV) on memory immune responses has not been thoroughly investigated due to limited availability of immunological research tools. Using single-cell RNA sequencing, we identified specific gene markers for the majority of T and B cell subsets in the spleens of mice. Our findings indicate that FMDV infection significantly reduces the proportions of memory cell populations (e.g., memory B cells, memory CD4