Articles and Topics
What is scarlet fever and how contagious is it?
Q: What is scarlet fever and how contagious is this illness?
A: Curt, scarlet fever is simply when the common “strep throat” infection is accompanied by a bright red skin rash. “Strep” (the bacteria streptococcus) infection of the throat is common in children, especially after 3 years of age. The symptoms include:

  • Sore and red throat, red tongue
  • Fever, headache, and swollen lymph nodes (“glands”) in the neck

  • Red skin rash on the cheeks, chest, back, and skin folds, which may feel rough like sandpaper


  • Strep throat and scarlet fever typically spread the same way as the common cold: by touching saliva or mucus from the nose; kissing on the lips; sharing food, cups and eating utensils; and coughing and sneezing into someone’s face. Strep infection is contagious from the day before the start of symptoms and during the period of illness, until 24 hours after the start of antibiotic treatment.

    If your child has the symptoms of strep throat or scarlet fever, see your doctor immediately. Although strep infection is usually mild, it can rarely lead to serious illnesses such as rheumatic fever (heart and joint problems) and kidney disease if it is not treated. Since many viruses also cause the same symptoms as strep throat, the doctor will need to examine your child and do a throat swab to make the diagnosis. If this test comes back positive, showing that your child does have strep, antibiotic treatment will be prescoted. Be sure to complete the full course of medication as prescoted by the doctor, or else the infection can return. For more information on the use of antibiotics, see my article on this web site titled, “Antibiotics: Using Them Safely.”

    The following precautions will help limit the spread of strep infection:
  • Don’t share food, cups and eating utensils.

  • Don’t kiss children on the mouth.

  • Wipe noses with a clean tissue, throw it away, and wash your hands.

  • Cough and sneeze into your elbow and away from other people.
Karen Sokal-Gutierrez M.D., M.P.H. Pediatrician