Herpes Simplex Encephalitis: Lack of Clinical Benefit of Long-Term Valacyclovir Therapy.

Despite the proven efficacy of acyclovir therapy, herpes simplex encephalitis (HSE) continues to cause substantial morbidity and mortality. Among patients with HSE treated with acyclovir (ACV), the mortality rate is approximately 14-19%. Among survivors, 45-60% have neuropsychological sequelae at 1 year. Thus, improving therapeutic approaches to HSE remains a high priority