Iowa Health Book: Pediatrics
"Baby Measles," Roseola Infantum, Exanthem Subitum, Sixth Disease
General information
Roseola is a very common disease of infants characterized by high fever and a rash. About one third of all infants have the typical illness, almost always between 4 months and 2 years of age. Many others probably catch the infection without ever feeling or acting sick.
The disease is caused by a virus, herpesvirus 6, related to but different from the other better known herpesviruses. It is not clear how roseola is spread, how contagious it is or how long it takes to become sick after exposure to an infected child.
The illness
Typical roseola is relatively easy to diagnose. The infant develops a rapidly rising temperature, usually up to 104 degrees F (40 degrees C) and sometimes even higher. Despite the fever, there are no other signs of infection such as diarrhea or vomiting, cough or runny nose. The baby alternates between being very comfortable, even happy, and acting irritable or fussy. S/he usually eats and drinks reasonably well.
After 3 to 5 days the temperature drops to normal, and within a few to 24 hours a rash develops. The rash consists of small pink spots, mostly over the neck, chest and body. It is usually very faint but may be heavy, and it lasts about a day, a little less or a little more. The characteristic feature of roseola is that the rash comes out after the temperature drops to normal. In most other childhood diseases the fever is present along with the rash.
The most worrisome complication for parents is a convulsion (seizure, fit). The rapid onset of fever, young age of the child and probably the nature of the virus combine to cause this problem which looks terrifying but rarely causes any aftereffects.
When to call your doctor
You should call our office if you feel frightened or worried about your child's illness.
Call our office immediately if your child has a convulsion. If you are alone, before you call turn the baby on his/her side so that the tongue does not block breathing. Do not leave your child unattended; place him/her nearby while you telephone. Although they seem to last forever, convulsions almost always stop within a few minutes.
Call us during regular office hours (or on weekends) if: your child is excessively sleepy or irritable; s/he develops persistent vomiting, diarrhea or cough, or pain with urination; fever lasts more than 5 days.
Treatment
The best way to make your child feel better is to bring down the fever. Keep clothing light; just a t-shirt and shorts or a diaper. Acetaminophen (Tylenol, Tempra, Panadol, Liquiprin) should be given four times a day as long as the temperature is elevated. If it goes over 104 degrees F (40 degrees C) sponging with a washcloth and lukewarm (doesn't feel hot or cold) water is helpful. Fever increases the body's need for fluids. It is helpful to encourage your child to drink; any liquid s/he likes is acceptable. Food, on the other hand, is not very important for these few days. Your child should be free to eat if hungry, but pushing food is not necessary.
There is no specific treatment for roseola; antibiotics do not help. Your doctor may prescnbe an antibiotic, however, if s/he thinks the fever might be caused by a bacterial illness.
Infants may continue normal play and toddling during the illness.
Contagion
Almost nothing is known about the contagiousness of roseola. It is believed that children are contagious from a few days before the fever until onset of the rash.
Return to group activities
Infants may go back to daycare and playground as soon as the fever and rash are over.
Common concerns
The diagnosis of roseola is never certain until the fever comes down to normal and rash appears. If your baby seems to be getting sicker, excessively sleepy or irritable, call your doctor.
Fever does not cause brain damage or retardation, even if it lasts for several days. As long as your child is acting fairly normal, temperatures as high as 104 degrees F to 105 degrees (40 degrees C to 40.6 degrees C) are not a cause for concern.
The use of cold water to bring down fever is uncomfortable and unnecessary and may result in a "rebound" to even higher temperatures. Rubbing alcohol should not be used for sponging.
Author: Moses Grossman, M.D.; Professor of Pediatrics, University of California (San Francisco) School of Medicine; San Francisco, CA
Editor, S. Michael Marcy, M.D.; Associate Editors, Michael E. Pichichero, M.D., and Richard H. Schwartz, M.D.
This material is not copyrighted and may be duplicated for distribution to parents or patients without charge.