The induction of CXCL8 and CXCL9 were highly significant in HSM (p = <0.0001) as well as HSE (p = 0.0006 and p = <0.0001, respectively) (Fig. 2a–b, Table 2), but the CSF-serum gradient was much more pronounced in HSM (factor of 40 and 12, respectively) compared to the HSE patient group (factor of 2.6 and 3.8, respectively) (Table 3). This evidence concerns the gene CXCL9 and herpes simplex encephalitis.