Epidemiology

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• Peak incidence: 6 months to 2 years

Etiology

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• Pathogen
  • HHV-6 (and in rare cases HHV-7)
  • Humans are the sole hosts.
• Route of transmission: droplet infection (e.g., saliva)

Pathophysiology

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Clinical features

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Tip

热退疹出，颜色粉红

Febrile phase

• Duration: 3–5 days
• Fever
  • Abrupt onset of high fever, in some cases > 40ºC (104ºF)
  • Febrile seizures are a potential complication of roseola (see “Complications” below).
• Cervical, postauricular, and/or occipital lymphadenopathy
• Inflamed tympanic membranes
• Nagayama spots: papular enanthem on the uvula and soft palate

Exanthem phase

• Duration: 1–3 days
• Characteristic presentation: subsequent sudden decrease in temperature and development of a patchy, maculopapular exanthem
  • Rose-pink in color; blanches upon pressure
  • Nonpruritic (in contrast to the drug allergy rash)
  • Originates on the trunk; sometimes spreads to the face and extremities

Diagnostics

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Treatment

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