In our study cohort, the elderly enrolled demonstrated a history of influenza virus vaccination and/or infection, based on the existing immunity to four vaccine strains before inoculation, and blank samples (with non-existing immunity) should be collected to evaluate the utility of these two biomarkers (MCEMP1 and SPARC) in guiding the clinical use of influenza vaccines covering a wider population. This evidence concerns the gene SPARC and influenza.