Scarlet fever is caused by an infection with group A streptococcus bacteria (usually strep throat). The bacteria make a toxin (poison) that can cause the scarlet-colored rash that gives this illness its name.
Not all streptococci bacteria make this toxin and not all kids are sensitive to it. Two kids in the same family may both have strep infections, but one child (who is sensitive to the toxin) may develop the rash of scarlet fever while the other doesn't.
Usually, if a child has this scarlet rash and other symptoms of strep throat, it can be treated with antibiotics. So if your child has these symptoms, it's important to call your doctor.
The rash is the most striking sign of scarlet fever. It usually begins looking like a bad sunburn with tiny bumps and it may itch. The rash usually appears first on the neck and face, often leaving a clear unaffected area around the mouth. It spreads to the chest and back, then to the rest of the body. In body creases, especially around the underarms and elbows, the rash forms classic red streaks. Areas of rash usually turn white when you press on them. By the sixth day, the rash usually fades, but the affected skin may begin to peel.
Aside from the rash, there are usually other symptoms that help to confirm a diagnosis of scarlet fever, including a reddened sore throat, a fever above 101ºF (38.3ºC), and swollen glands in the neck. The tonsils and back of the throat may be covered with a whitish coating, or appear red, swollen, and dotted with whitish or yellowish specks of pus. Early in the infection, the tongue may have a whitish or yellowish coating. A child with scarlet fever also may have chills, body aches, nausea, vomiting, and loss of appetite.
When scarlet fever happens because of a throat infection, the fever usually stops within 3 to 5 days, and the sore throat passes soon afterward. The scarlet fever rash usually fades on the sixth day after sore throat symptoms began, but skin that was covered by rash may begin to peel. This peeling may last 10 days.
The infection itself is usually cured with a 10-day course of antibiotics, but it may take a few weeks for tonsils and swollen glands to return to normal.
In rare cases, scarlet fever may develop from a streptococcal skin infection like impetigo. In these cases, the child may not get a sore throat.
The bacterial infection that causes scarlet fever is contagious. A child who has scarlet fever can spread the bacteria to others through nasal and throat fluids by sneezing and coughing. If a child has a skin infection caused by strep bacteria, like impetigo, it can be passed through contact with the skin.
In everyday life, there is no perfect way to avoid the infections that cause scarlet fever. When a child is sick at home, it's always safest to keep that child's toothbrush, drinking glasses, and eating utensils separate from those of other family members, and to wash these items thoroughly in hot soapy water. Wash your own hands often as you care for a child with a strep infection.
If your child has a rash and the doctor suspects scarlet fever, he or she will usually take a throat culture (a painless swab of throat secretions) to see if the bacteria grow in the laboratory. If a strep infection is confirmed, the doctor will prescribe an antibiotic for your child to be taken for about 10 days.
Caring for Your Child
A child with severe strep throat may find that eating is painful, so serving soft foods or a liquid diet may be best. Include soothing teas and warm nutritious soups, or cool soft drinks, popsicles, or slushies. Make sure that your child drinks plenty of fluids. You can give over-the-counter acetaminophen or ibuprofen for the throat pain.
If the rash itches, make sure that your child's fingernails are trimmed short so skin isn't damaged through scratching. Try an over-the-counter anti-itch medicine to help relieve the itching.
When to Call the Doctor
Call the doctor whenever your child suddenly develops a rash, especially if it is accompanied by a fever, sore throat, or swollen glands. This is especially important if your child has any of the symptoms of strep throat, or if someone in your family or in your child's school has recently had a strep infection.
Reviewed by: Raluca Papadopol, MD
Date reviewed: December 2014