Roseola is a generally mild viral illness that usually affects babies and young children. The condition typically causes several days of fever, followed by a rash. The disease also has other names; Roseola infantum, exanthematous fever, and three-day-rash.
Two common strains of the herpes virus cause roseola. It usually affects children between 6 months and 3 years of age, though it occasionally affects adults. It's extremely common - so common, in fact, that most children have been infected by the time they enter kindergarten.
Some children develop only a very mild case of roseola and never show any clear indication of illness, while others experience the full range of signs and symptoms. The infection can occur at any time of the year.
Roseola typically isn't serious. Rarely, complications from a very high fever can result. Treatment includes bed rest, fluids and medications to reduce fever.
Signs and symptoms
If your child is exposed to someone with roseola and becomes infected with the virus, it generally takes a week or two for signs and symptoms of infection to appear — if they appear at all. It's possible to become infected with roseola but have symptoms too mild to be readily noticeable. Signs and symptoms may include:
Roseola is a childhood illness caused by two strains of herpes virus. Common signs of roseola are fever and a rash on the trunk and neck.
Other signs and symptoms of roseola may include:
The most common cause of roseola is the human herpes virus 6 (HHV6), but the cause also can be another herpes virus — human herpes virus 7 (HHV7). These herpes viruses are related to, but different from, those that cause cold sores and genital herpes.
Like other viral illnesses, such as a cold, roseola spreads from person to person through contact with an infected person's respiratory secretions or saliva. For example, a child who drinks out of the cup of another child who has roseola could contract the virus.
Roseola is contagious even if no rash is present. That means the condition can spread while an infected child has a fever but before it's clear that the child has roseola. Watch your child for signs of roseola if your child has interacted with another child who has the illness. Sometimes it's not clear how a child contracted roseola.
Unlike chickenpox and other childhood viral illnesses that spread rapidly, roseola rarely results in a communitywide outbreak.
Older infants are at greatest risk of acquiring roseola because they haven't had time yet to develop antibodies against many viruses. While in the uterus, babies receive antibodies from their mothers that protect them as newborns from contracting infections such as roseola. But that immunity fades with time. The most common age for a child to contract roseola is between 6 and 12 months.
When to seek medical advice
Roseola can cause a high fever — 39 C or higher. Call your child's pediatrician anytime your child has a fever greater than 39 C. Your doctor may want you to bring your child in for a physical exam to rule out more serious causes of fever than roseola.
Your child could have a convulsion (febrile seizure) if his or her fever becomes too high or spikes too quickly. However, usually by the time you notice your child's high temperature, the threat of a possible seizure has already passed. If your child does have an unexplained seizure, seek medical care immediately.
If your child has roseola and the fever lasts more than seven days, or if the rash doesn't improve after three days, call your child's doctor.
If your immune system is compromised and you come in contact with someone who had roseola, contact your doctor. You may need monitoring for a possible infection which, for you, could be more severe than it is for a child.