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Roseola Infantum

(Exanthem Subitum; Pseudorubella)


Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Reviewed/Revised May 2023
Topic Resources

Roseola infantum is an infection of infants or very young children caused by human herpesvirus 6B (HHV-6B) or, less commonly, HHV-7. The infection causes high fever and a rubelliform eruption that occurs during or after defervescence, but localizing symptoms or signs are absent. Diagnosis is clinical, and treatment is symptomatic.

Roseola infantum is the most well-described illness to result from human herpesvirus-6 (HHV-6); 2 distinct HHV-6 species, A and B, exist with most if not all clinical disease linked to HHV-6B infection. HHV-6B may also cause central nervous system (CNS) disease in patients who are immunocompromised (eg, hematopoietic stem cell transplant recipients).

Roseola infantum occurs most often in the spring and fall. Minor local epidemics have been reported.

Symptoms and Signs of Roseola Infantum

The incubation period is about 5 to 15 days. Fever of 39.5 to 40.5° C begins abruptly and persists 3 to 5 days without any localizing symptoms or signs. Despite the high fever, the child is usually alert and active, although febrile seizures Febrile Seizures Febrile seizures are diagnosed in children 6 months to 5 years of age who have fever > 38° C that is not caused by a central nervous system infection and who have had no previous afebrile... read more may occur.

Cervical and posterior auricular lymphadenopathy often develops.

Encephalitis or hepatitis occurs rarely.

The fever usually decreases rapidly on the 4th day, and when the fall occurs, a macular or maculopapular exanthem usually appears prominently on the chest and abdomen and, to a lesser extent, on the face and extremities; it lasts for a few hours to 2 days and may be unnoticed in mild cases.

In 70% of HHV-6 infections, the classic exanthem does not occur.

Pearls & Pitfalls

  • In roseola infantum, the characteristic rash occurs with defervescence.

Diagnosis of Roseola Infantum

  • History and physical examination

Roseola infantum may be suspected when a child aged 6 months to 3 years develops typical symptoms and signs.

Testing is rarely needed, but diagnosis of roseola infantum can be confirmed by culture or serologic tests.

Molecular assays (eg, quantitative polymerase chain reaction) are available but are more commonly used to detect viral reactivation.

Treatment of Roseola Infantum

  • Supportive care

Treatment of roseola infantum is generally symptomatic.

Foscarnet or ganciclovir has been used to treat some patients who are immunosuppressed who have severe disease, particularly encephalitis, but controlled trials are lacking.

Drugs Mentioned In This Article

Drug Name Select Trade
Cytovene, Vitrasert, Zirgan
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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