Roseolovirus
Diseases associated with this genus include: HHV-6: sixth disease ( roseola infantum , exanthema subitum ) ; HHV-7: symptoms analog to the 'sixth disease' . 
<triplet> HHV-6 <subj> roseola <obj> has effect <triplet> roseola <subj> HHV-6 <obj> has cause <subj> HHV-7 <obj> has cause