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Roseola Infantum

(Exanthem Subitum; Pseudorubella)


Brenda L. Tesini

, MD, University of Rochester School of Medicine and Dentistry

Last full review/revision Jul 2021| Content last modified Jul 2021

Roseola infantum is a viral infection of infants or very young children that causes a high fever followed by a rash.

  • Roseola infantum is caused by human herpesvirus-6.
  • Typical symptoms include high fever that begins suddenly and sometimes a rash that develops after the temperature returns to normal.
  • The diagnosis is based on symptoms and the age of the child.
  • Treatment aims to relieve symptoms.

Roseola infantum occurs throughout the year, most often in the spring and fall. Sometimes minor local outbreaks occur. The usual cause is herpesvirus-6, one of the many human herpesviruses. Most children who develop roseola infantum are between 6 months and 3 years of age.

Symptoms of Roseola Infantum

Roseola infantum symptoms begin about 5 to 15 days after infection. A fever of 103 to 105° F (about 39.5 to 40.5° C) begins abruptly and lasts for 3 to 5 days. In 5 to 15% of children, seizures occur as a result of high fever, particularly as the fever begins and rises quickly. Despite the high fever, the child is usually alert and active. A few children have a mild runny nose, sore throat, or an upset stomach. The lymph nodes at the back of the head, the sides of the neck, and behind the ears may be enlarged. The fever usually disappears on the fourth day.

About 30% of children with roseola infantum develop a rash within a few hours to, at most, a day after the temperature falls. The rash is red and flat. It occurs mostly on the chest and abdomen and less extensively on the face, arms, and legs. The rash is not itchy and may last from a few hours to 2 days.

Diagnosis of Roseola Infantum

  • A doctor's evaluation

A doctor suspects roseola infantum when typical symptoms (particularly development of a rash after a fever goes away) appear in a child aged 6 months to 3 years. Tests are rarely done, but the diagnosis of roseola infantum can be confirmed with blood tests.

Treatment of Roseola Infantum

  • Acetaminophen or ibuprofen for fever to provide comfort

Fever is treated with acetaminophen or ibuprofen. The seizures and rash do not require any specific treatment, but because they are frightening, most parents bring their child to the doctor for evaluation.

If the disease is severe in children with a weakened immune system, doctors may try treating them with the antiviral drugs foscarnet or ganciclovir.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Acetaminophen TYLENOL
ganciclovir CYTOVENE
ibuprofen ADVIL, MOTRIN IB
foscarnet FOSCAVIR

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