This was statistically significant for the cohort as a whole (CD25+ pertussis: R2 = 0.0549, p = 0.0052; CD25+ pertussis + LCC: R2 = 0.0453, p = 0.0122; CD25+IFN-γ+ pertussis: R2 = 0.0379, p = 0.0203; CD25+IFN-γ+ pertussis + LCC: R2 = 0.0478, p = 0.0095), but not when analyzed separately for HCMV− and HCMV+ donors due to decreased power. The gene discussed is IFNG; the disease is pertussis.