Roseola is a common infection that usually affects children by age 2. It's caused by a virus that spreads from person to person. It can cause a high fever followed by a rash that doesn't itch or hurt. About a quarter of the people with roseola get a rash.

Roseola, also known as sixth disease, usually isn't serious, and it goes away on its own in a week or so. Treatment of roseola includes cool cloths and medications to reduce fever.

Seek immediate medical care

Your child could have a convulsion (febrile seizure) if the fever becomes high or spikes quickly. If your child has an unexplained seizure, seek medical care immediately.

Call your child's health care provider

Call your child's health care provider if:

• Your child has a high fever, over 103 F (39.4 C)
• The rash doesn't improve after three days and the fever returns

Call your health care provider

Contact your health care provider if anyone in the household has a problem with their immune system and comes in contact with someone who has roseola. They may need monitoring for a possible infection that could be more severe than it is for someone with a strong immune system.

Roseola is caused by a virus, usually human herpes virus 6 or sometimes human herpes virus 7. It is spread by contact with an infected person's saliva, such as when sharing a cup, or through the air, such as when a person with roseola coughs or sneezes. It can take about 9 to 10 days for symptoms to develop after exposure to an infected person.

Roseola is no longer contagious after the fever has been gone for 24 hours.

Unlike chickenpox and other childhood viral illnesses that spread rapidly, roseola rarely results in a communitywide outbreak. The infection most often occurs in the spring and fall.

The risk of roseola is highest in older infants. It is most common between 6 and 15 months. Older infants are at greatest risk of acquiring roseola because they haven't had time yet to develop their own antibodies against many viruses. Newborns are protected by antibodies received from their mothers during pregnancy. But this immunity decreases with time.

Roseola is usually a mild disease, but it can cause complications.

Seizures in children

Occasionally a child with roseola experiences a seizure brought on by a sudden fever (febrile seizure). If this happens, your child might briefly lose consciousness, fall down, and have jerking arms and legs for several seconds to minutes.

If your child has a seizure, seek emergency care. Although frightening, febrile seizures in otherwise healthy children tend to be short-lived and are rarely harmful.

Concerns for people with weak immune systems

Roseola is of greater concern in people with a weak immune system. You might have a weak immune system, for example, if you've recently had bone marrow transplant. People with a weak immune system have less resistance to viruses. They tend to develop more-severe roseola or complications such as pneumonia or encephalitis. Encephalitis is a potentially life-threatening inflammation of the brain.

There is no vaccine to prevent roseola. You can protect others by keeping home a child with fever until the fever has been gone for 24 hours. Then, even if a roseola rash is present the disease isn't contagious.

Most people have antibodies to roseola by the time they're of school age, making them immune to a second infection. Even so, if one household member gets the virus, make sure that all family members wash their hands often to prevent spread of the virus to anyone who isn't immune.

Roseola might be diagnosed based on the symptoms. The initial symptoms are similar to many other childhood illnesses, such as measles. A roseola rash often starts on the chest or back. A measles rash begins on the head.

Sometimes a blood test is done to confirm the diagnosis.

There's no treatment for roseola. Most children recover within a week of the onset of the fever. With your health care provider's advice, consider giving your child nonprescription fever and pain medications made for infants or children as a safer alternative to aspirin. Examples include acetaminophen (Tylenol, others) and ibuprofen (Children's Advil, others).

Use caution when giving aspirin to children or teenagers. Though aspirin is approved for use in children older than age 3, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. This is because aspirin has been linked to Reye's syndrome, a rare but potentially life-threatening condition, in such children.

There's no specific treatment for roseola. Some health care providers may prescribe the antiviral drug ganciclovir for people who have weakened immune systems.

Like most viruses, roseola just needs to run its course. Once the fever subsides, your child will likely feel better soon. Roseola rash is harmless and clears up in 1 to 3 days. No creams or ointments are needed.

To treat your child's fever at home, your health care provider may recommend:

• Plenty of rest. Let your child rest in bed until the fever goes away. Use lightweight clothing and covers.
• Plenty of fluids. Offer your child clear fluids to drink to prevent dehydration. Examples are water, ginger ale, lemon-lime soda, clear broth, an electrolyte rehydration solution (Pedialyte, others) and sports drinks, such as Gatorade or Powerade. Remove the gas bubbles from carbonated fluids. You can do this by letting the bubbly drink stand or by shaking, pouring or stirring it. Removing the bubbles will help your child avoid the added discomfort of excess burping or intestinal gas.
• Cool cloth or a sponge bath. Give your child a lukewarm sponge bath or apply a cool, damp cloth to the forehead. Doing this can soothe the discomfort of a fever.

Here's some information to help you get ready for your child's medical appointment.

Information to gather in advance

• Symptom history. List any symptoms your child has had, and for how long.
• Key medical information. Include any other health problems and the names of any medications your child is taking.
• Recent exposure to possible sources of infection. List any possible sources of infection, such as other children who've had a high fever or a rash in the last few weeks.
• Questions to ask. List your questions so that you can make the most of your time with your health care provider.

Questions to ask your health care provider about your child's condition include:

• What is the most likely cause of my child's signs and symptoms?
• Are there other possible causes?
• What treatment do you recommend?
• What nonprescription fever medications are safe for my child, if any?
• What else can I do to help my child recover?
• How soon before symptoms improve?
• Is my child contagious? For how long?
• How do we reduce the risk of infecting others?

What to expect from your doctor

Your health care provider may ask:

• What are your child's signs and symptoms?
• When did you notice these signs and symptoms?
• Have your child's signs and symptoms gotten better or worse over time?
• Have any children with whom your child interacts had a recent high fever or a rash?
• Has your child had a fever? How high?
• Has your child had diarrhea?
• Has your child continued to eat and drink?
• Have you tried any at-home treatments? Has anything helped?
• Has your child recently had any other medical conditions?
• Has your child recently taken any new medications?
• Is your child in school or child care?
• What else concerns you?

What you can do in the meantime

Before your appointment, encourage your child to rest and drink fluids. You may be able to ease fever-related discomfort with a lukewarm sponge bath or a cool cloth to the forehead. Ask your health care provider whether nonprescription fever medications are safe for your child.