Yes, Acyclovir does need viral nucleic acid for its activation.. but what the researchers in this https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2151143/ article did was-- they monitored the level of plasma aciclovir and its metabolite and correleated it with the neuropsychiatric symptoms.. and found out that after hemodialysis (low plasma level of drug) the the symptoms subsided...