Roseola

(Roseola Infantum, Exanthem Subitum, Sixth Disease)

The Facts

Roseola is a viral infection that begins with a sudden high fever and is followed by the appearance of a rose-coloured rash. It used to be referred to as "sixth disease" because it is the sixth rash-causing disease that children usually develop.

Roseola is generally a childhood infection, with most cases occurring between 6 months and 3 years of age. This infection rarely occurs later in life; however, adults can develop this viral infection. Interestingly, most cases of roseola appear during the spring and fall, but the reasons for this remain unknown.

Roseola is a mild and short-lived infection. Like the common cold, the body is capable of curing the infection on its own. Keeping your child well rested and hydrated will help their bodies clear the infection.

The Causes

Roseola is a common childhood infection that is caused by the same family of viruses that is responsible for chickenpox and shingles. This virus can be spread by tiny droplets of fluid that go into the air when someone who is infected talks, coughs, laughs, or sneezes. This usually happens before people who are infected develop symptoms. The infection is spread when people inhale the droplets or touch them and then touch their mouth or nose. Older children and adults should cover their mouths or noses when coughing or sneezing to prevent spreading the virus to others.

Symptoms And Complications

For the first week or two after becoming infected, the virus will multiply in the body, usually causing no symptoms. Children may appear irritable during this time. After this period of incubation, symptoms begin to appear. Children will develop a sudden high fever as high as 39.5°C to 40.5°C (103°F to 105°F) lasting 3 to 5 days. Despite the fever, children are usually alert and do not appear ill. However, some children may also have a mild sore throat, runny nose, cough, swollen glands, and mild diarrhea either before or during the fever. Some children also experience fatigue, swollen eyelids, and a decreased appetite.

The fever will usually subside by the fourth day, but this is followed by a characteristic faint, rosy-pink widespread rash that may develop. Small, flat, discoloured spots on the skin with tiny raised bumps (2 mm to 5 mm in diameter) first appear on the trunk of the body. This rash may then spread to the neck and legs, but rarely will it involve the face. This rash is neither itchy nor pus-forming and tends to whiten when pressure is applied to the reddened area. Typically, the rash will clear within a few hours, but may last up to 2 days. For some people, the rash may even be mild enough to go unnoticed or may not even appear.

The sudden onset of a high fever may cause convulsions or seizures called febrile seizures. This is more common in infants and young children between the ages of 6 months and 3 years and occurs in 6% to15% of children. Fortunately, febrile seizures are usually very short and are very rarely harmful. If your child does experience a febrile seizure that lasts for more than 5 minutes, call for emergency medical attention. Aside from febrile seizures, complications in children are rare.

Roseola in adults can cause severe complications including meningoencephalitis, an infection of the brain tissue and its surrounding layers, or hepatitis, an inflammation of the liver.

Making A Diagnosis

Your doctor will examine your child's skin and ask about their symptoms to determine whether they have roseola and to rule out other causes of the symptoms. A diagnosis is usually made based on the appearance of the characteristic rash, but it may need to be confirmed with blood tests.

Treatment And Prevention

There is currently no vaccine available to prevent infection with the virus that causes roseola. Fortunately, roseola is a relatively mild infection that will go away without treatment. It is best treated by managing symptoms and keeping the infected person well rested and hydrated. Acetaminophen* or ibuprofen are usually recommended to treat a high fever and are safe for children.

Don't give children who have symptoms of the flu, chickenpox, or other viral infections acetylsalicylic acid (ASA) or ASA-containing products since this can lead to Reye's syndrome, a serious condition that can cause a fatal inflammation of the brain and liver. If symptoms subside, a follow-up with your doctor is only necessary if complications develop. Because roseola is a viral infection, antibiotics are not effective. Antiviral medications such as foscarnet or ganciclovir may be prescribed in severe cases.

*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. This article lists medications by their common names. For information on a given medication, check our Drug Information database. For more information on brand names, speak with your doctor or pharmacist.