Roseola

What is roseola?

Roseola is a very common viral infection that causes a fever, followed by a rash. The most common virus that causes roseola is human herpes virus 6B.

Who is most at risk of a roseola infection?

Roseola usually affects children from 6 months to 2 years of age. Although it is not common, roseola can sometimes occur before 6 months of age and after 2 years of age.

Newborn babies are not at high risk for roseola because of the antibodies they receive from their mothers. These antibodies protect them against infections, but this immunity fades as they get older.

By school age, most children will have had a roseola infection. The antibodies that they produce to fight this infection will protect them from roseola in the future.

Signs and symptoms of roseola

Roseola rash on torso

There are two main symptoms of roseola.

• The first symptom is a sudden, high fever, sometimes higher than 40°C (104°F). The fever may last about three to five days.
• When the fever passes, a rash often appears. This rash has many small pink spots, which are usually flat but may be slightly raised. The rash usually starts on the chest, abdomen and back and may later spread to the face and limbs. It lasts about four days but does not itch.

The symptoms of roseola are usually mild. While the infection itself rarely leads to severe illness, 10% to 15% of children with roseola can experience a febrile seizure.

Other symptoms of roseola include:

• irritability
• sore throat
• runny nose
• cough
• fatigue
• mild diarrhea
• decreased appetite
• swollen eyelids
• swelling of the lymph nodes in the neck
• swelling of the fontanelle (in infants)

Not every child with roseola will develop these symptoms. If they occur at all, it is usually before the rash appears.

How roseola spreads

Roseola spreads from person to person through contact with an infected person's saliva, for example by sharing a cup, or nasal secretions, for example if a person sneezes.

A person can spread the virus even if they do not show any symptoms. Infection with roseola can occur at any time of the year.

How roseola is diagnosed

Roseola is easy to diagnose if it involves a fever followed by rash. However, not all cases of roseola look the same. For example, sometimes there is no rash after the initial fever. In addition, many other viral infections can look similar to roseola. There is no standard test to confirm roseola.

In some cases, during the initial phase of fever in young children who are irritable, health-care providers may perform urine or blood tests to screen for bacterial infections.

How to treat roseola

The best way to treat roseola is to manage the symptoms until the infection passes. Because roseola is caused by a virus, rather than bacteria, antibiotics are not effective.

Medications

To reduce fever, give your child over-the-counter medications such as acetaminophen or ibuprofen. These medications may be in liquid form. Learn how to give liquid medications to your child.

Clothing

Keep your child lightly dressed. Overdressing or bundling your child may make them uncomfortable. If your child is having chills or shivers, give them a light blanket. Keep the room temperature at a level that is comfortable for you when lightly dressed.

Extra fluids

Encourage your child to drink extra fluids. It does not matter whether the drinks are warm or cool. As long as your child is drinking well, do not worry if their appetite decreases for a few days.

How to prevent roseola

There is no vaccine to prevent roseola and it is difficult to avoid exposure when it can be spread even when people have no symptoms.

The best way to prevent the spread of germs is to wash hands frequently. If your child already has roseola, keep them at home until their fever is gone.

When to see a health-care provider

See a health-care provider if:

• your child seems very unwell, lethargic or irritable
• your child's fever lasts more than five days
• the rash does not improve after a few days
• your child’s fever does not respond to over-the-counter fever medications
• the spots of the rash look purple or blood-coloured

Go to your nearest emergency department right away if your child has a febrile seizure.

Your child may show physical changes when their condition is serious or when their condition gets worse. Parents and caregivers can learn how to spot these signs in order to seek help from a health-care provider.