Human Herpesvirus 6 (HHV-6) Infection in the Central Nervous System

Human herpesvirus 6 (HHV-6) was isolated from patients with exanthem subitum (ES) with a high frequency, and it is now believed that this virus causes ES as a primary infection in childhood. HHV-6 infection is highly prevalent in early childhood and this virus may infect infants through the saliva mainly from mother to child. HHV-6 has a tropism to CD4+ cells and destroys cells in vitro. Although children recover from ES without any sequelae, neurological symptoms associated with exanthem subitum are often observed, and we could detect HHV-6 in the cerebrospinal fluid of ES patients. This result suggests that HHV-6 may invade the central nervous system and cause neurological symptoms.