Viral exanthems (eg-ZAN-them) are skin rashes or eruptions caused by infections with certain types of viruses.
An exanthem is a rash or eruption on the skin. "Viral" means that the rash or eruption is a symptom of an infection due to a virus.
Viral exanthems can be caused by many viruses, such as enteroviruses, adenovirus, chickenpox, measles, rubella, mononucleosis, and certain types of herpes infection. Viral exanthems are very common and can vary in appearance. Most cause red or pink spots on the skin over large parts of the body. Often, these don't itch, but some types can cause blisters and be very itchy.
Many of the infections that cause viral exanthems also can cause fever, headaches, sore throat, and fatigue. Most will run their course in a few days or a couple of weeks and will clear up without treatment.
Viral infections can be highly contagious, though, so anyone with a viral exanthem should avoid close contact with others until the rash is gone.
Viral exanthems and the infections that cause them usually aren't treatable, but they almost always clear up quickly on their own with no long-term problems. Some serious bacterial infections also cause rashes, so it's important for the doctor to evaluate an exanthem. Getting the proper immunizations can greatly reduce someone's risk of many viral and bacterial infections.
All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts.
