Snapshot A 4-year-old child develops a high fever and no other physical findings. On the third day of illness, the fever rapidly declines and a spotty, maculopapular rash develops on the trunk and spreads to the extremities. Introduction Common childhood infection caused by Human Herpesvirus 6 (HHV-6) or, less commonly, Human Herpesvirus 7 (HHV-7) Viral exanthem appears as prodrome sequence notable for acute high fever (104 F) followed by classic rash with no other symptoms Epidemiology most often occurs in children ages 6-18 months Presentation Symptoms prodrome acute, high fever (> 104 degrees F) 1-5 days duration minimal other clinical symptoms rash diffuse, splotchy, maculopapular rash spreads quickly from trunk peripherally to entire body rash duration is approximately 24 hours leave no scars Physical exam usually present to the clinician with high fever no other physical findings are evident until rash appears as described may observe febrile seizures secondary to high fever Evaluation Diagnosis based primarily on clinical observations and patient history PCR or viral culture may be helpful in identifying HHV-6, but usually not necessary Differential Other viral exanthems Treatment Medical management observation alone usually self-resolving and does not require treatment symptom management tylenol for high fever Prognosis, Prevention, and Complications Prognosis excellent Prevention no preventive measures are available at this time Complications febrile seizure may result secondary to rapid onset of high fever