Roseola infantum: Roseola infantum is another name for roseola, also formally called roseola infantilis. The following is a brief rundown on roseola:
Cause: Roseola is caused by a virus called human herpesvirus 6 (HHV-6) and, possibly, human herpesvirus 7 (HHV-7).
Age range: Roseola is most common in children 6 months to 24 months of age.
Spread: Roseola is spread from person to person, but it is not known how. Roseola is not very contagious.
Initial symptoms: These include a high fever that lasts for 3 to 5 days, runny nose, irritability, eyelid swelling, and tiredness.
The rash: When the fever disappears, a rash appears. The rash is mainly on the face and body.
Course: The rash lasts for about 24 to 48 hours. Roseola usually goes away without any treatment.
Complications of roseola are rare.
Seeing the doctor: A child with fever and rash should be excluded from child care until seen by a physician.
Return to child care: A child with rash and no fever may return to child care.
Because the rash appears so suddenly (right after the fever dramatically departs), the disease is also sometimes called exanthem subitum.