In person with Hepatitis B on Tenofovir therapy along with patients infected with BK virus in patient of allograft renal transplant and in cytomegalovirus PCR in blood of patient of liver transplant viral load is necessary so viral load is done by real time PCR but it in hsv causing temporal aeritis there is a search no role of viral load so there is no such need of real time PCR This is replaced by HSV DNA in CSF by PCR