Human herpes virus 6 and multiple sclerosis.

OBJECTIVES: To systematically review the published evidence for a relationship between human herpes virus 6 (HHV-6) and multiple sclerosis (MS).
MATERIALS AND METHODS: The medical literature was searched using MEDLINE and the Cochrane database. Retrieved studies are presented according to the experimental technique(s) used. The studies are rated for quality using a priori defined criteria.
RESULTS: Twenty-eight studies were retrieved. A total of 12 different experimental techniques were used. Four of these techniques provided evidence for a relationship between HHV-6 and MS, but none were able to show a causative relationship.
CONCLUSIONS: The available literature provides some support for a relationship between HHV-6 and MS. The limitations of the available studies and directions for future research are discussed.