What Does a Roseola Rash Look Like?

A pink or red rash is a sign of roseola.

Roseola infantum is a common childhood disease caused by infection with human herpesvirus 6 (HHV-6). The typical roseola infantum patient is a 9- to 12-month-old infant who develops a high fever, sometimes accompanied by a seizure (febrile seizure). After 3 days, the fever quickly goes down and a rash that looks like measles appears.

Symptoms and signs of roseola infantum include the following:

• Sudden onset of high fever (104 F/40 C)
• Fever lasts 3 days.
• Seizure occurs in about 15% of patients.
• Fever disappears quickly and a mild, pink, measles-like rash (morbilliform exanthem) appears.
• Rash is either small, pale, pink bumps or flat, red areas that are 1-5 mm in diameter.
• Rash may last 2 days.
• Red papules may occur inside the mouth on the soft palate and the base of the uvula (Nagayama spots).

The following signs and symptoms may accompany the fever and/or rash:

• Feeling unwell (malaise)
• Irritability
• Decreased eating and drinking
• Increased crying
• Cough
• Vomiting
• Diarrhea
• Bulging fontanelle

For the most part, human herpesvirus 6 (HHV-6) causes roseola in infants.

Other causes include human herpesvirus 7 (HHV-7), enteroviruses (coxsackieviruses A and B, echoviruses), adenoviruses, and parainfluenza virus type 1.

The following tests help diagnose roseola infantum:

• Complete blood cell (CBC) count
• Urinalysis
• Blood cultures
• Cerebrospinal fluid (CSF) examination by a spinal tap
• Virologic studies

If a febrile seizure accompanies fever, it may be necessary to undergo a seizure workup.

There is no medical treatment or cure for the human herpesvirus 6 (HHV-6) infection that causes roseola infantum. In most cases, roseola infantum is a benign condition and it goes away on its own.

Treatment aims to relieve symptoms and signs and may include fever reducers (antipyretics) such as acetaminophen (Tylenol).

The rash usually does not require treatment.

Complications are rare for roseola infantum. Children who have seizures with roseola are not expected to have further seizures.

Simple hygiene measures such as hand washing for at least 20 seconds with soap and water may help prevent the spread of roseola.