Virus
Human herpesvirus 6
Roseola infantum (sixth disease)
HYOO-mun HER-peez-VY-rus siks
High-yield clue
High fever for a few days followed by a rash that appears as the fever breaks in a toddler is the classic roseola clue.
Overview
A ubiquitous double-stranded DNA betaherpesvirus that infects most people in early childhood and is the classic cause of roseola, useful for studying post-fever exanthem vocabulary and herpesvirus latency.
Classification
- DNA virus
- Double-stranded DNA
- Family Herpesviridae, Betaherpesvirinae
- Genus Roseolovirus
Lab & identification clues
- Roseolovirus classification concept
- T-lymphocyte tropism vocabulary
- Chromosomally integrated HHV-6 (ciHHV-6) concept
- PCR detection vocabulary
Associations
- Roseola infantum / exanthem subitum (sixth disease)
- Febrile seizure association in young children
- Lifelong latency after primary infection
- Reactivation framing in immunocompromised hosts
Commonly confused with
- Measles virus
- Parvovirus B19 (fifth disease)
Your notes
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.