Herpes 2000 Oct;7(3):70-75
Department of Microbiology, Osaka University Medical School, Osaka University, Osaka, Japan.
First isolated in 1986 from patients with lymphoproliferative disorders, human herpesvirus 6 (HHV-6) is a B-herpesvirus with two variants: HHV-6A and HHV-6B. HHV-6B is the major causal pathogen of exanthem subitum, a predominantly benign exanthematous disease of infants with occasional complications in the central nervous system.
Infection with HHV-6 is common among the general population and the virus mainly seems to be transmitted from mother to infant via saliva.
Following primary infection, HHV-6 persists latently and can reactivate in immunocompromised hosts, such as in individuals with AIDS or in transplant or multiple sclerosis patients where it possibly causes encephalitis and pneumonitis.
Its precise role in these conditions is not well understood and further study is needed.