Multiple linear regression analysis using RV load as a continuous predictor variable, viral coinfection as a binary predictor variable (0 = no viral coinfection; 1 = viral coinfection), and CXCL10 as the response variable showed that RV load was significantly correlated with CXCL10 and that viral coinfection drove a significant increase in CXCL10 protein measured compared with single infections (Fig. S2 B). This evidence concerns the gene CXCL10 and coinfection.