ABSTRACT
Herpes infections were first recognized in ancient Greece. Hippocrates and other scholars described the skin lesions of the herpes simplex viruses (HSVs) as herpein meaning to creep or crawl. The herpes family of viruses is ubiquitous and the lifetime risk of acquiring a herpesvirus approaches 100%. Acute infections cause a myriad of clinical syndromes and vary depending on the type of virus, but rarely cause encephalitis. The herpesviruses establish latency in the nervous system and may reactivate causing various clinical syndromes, including encephalitis. The risk of reactivation and subsequent encephalitis increases with age and immunosuppression. The herpesviruses are the most commonly identified etiologic agents of acute viral encephalitis in the western hemisphere (1-4). Additionally, HSV type 1 is the most common fatal cause of acute viral encephalitis (5).
