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Betaherpesvirinae

Betaherpesvirinae is a subfamily of viruses in the order Herpesvirales, in the family Herpesviridae. Mammals serve as natural hosts. There are currently 18 species in this subfamily, divided among 4 genera. Diseases associated with this subfamily include: HHV-5: congenital CMV infection. HHV-6: ' sixth disease' (roseola infantum, exanthem subitum). HHV-7: symptoms analog to the 'sixth disease'.