This protocol is designed to study herpes simplex virus infection in neonates with skin, eye and mouth disease, making possible assessment of the potential benefits/risks of suppressive acyclovir therapy as an antiviral leading to more rapid clearance of virus and decreasing morbidity and neurologic impairment. Treatment is provided at the GCRC for fourteen consecutive days and then monthly assessment is done on days 1, 7 and 14. One spinal tap is performed on Day 1. Outpatient visits are then monthly for six months for neurological and developmental assessments.