HSV-1 and HSV-2 are well known etiologic agents of gingivostomatitis, conjunctivitis, keratitis, herpetic whitlow, and genital infections as well as encephalitis, aseptic meningitis, atypical pneumonias and a wide variety of other clinical conditions. Quantitative HSV DNA PCR is the ideal diagnostic tool for CNS specimens, since HSV will rarely grow from CSF in cell culture. Quantitative PCR can be used to detect the presence of the virus as well as track the course of infections and response to treatment.