Roseola Infantum

Roseola infantum is a common disease of childhood caused by a primary infection with human herpesvirus 6 (HHV-6) and less frequently, by human herpesvirus 7 (HHV-7). This disease, also known as exanthema subitum and sixth disease, presents in children ages six to 12 months with 90% of cases occurring in children younger than two years. Caused by the B variant of HHV-6, patients with the virus classically present with an acute onset of a high-grade fever up to 40 C (104 F) for three to five days. The child will experience a rapid defervescence of the fever with accompanying nonpruritic, pink papular rash that begins on the trunk. It is found universally and has been discovered to be the cause of 10% to 45% of febrile illness in infants. Due to the high fever and the ability of the virus to cross the blood-brain barrier, 15% of children will also experience an acute febrile seizure during the febrile phase of the illness.  Roseola infantum is a clinically diagnosed, self-limited illness that can be treated symptomatically. HHV-6 will likely remain latent in immunocompetent patients but can be a major cause of morbidity and mortality in patients who are immunosuppressed.