Scarlet fever is an infectious disease caused by a group A Streptococcus (GAS) bacteria that can affect people of all ages, but is most common in children between the ages of 5 and 15. It is characterized by a bright red rash that covers most of the body, and may be accompanied by fever, sore throat, swollen lymph nodes, and other symptoms.

Scarlet fever is spread through direct contact with infected people, or through contact with contaminated objects or surfaces. The bacteria typically enter the body through the mouth or nose, and can cause a variety of infections, including strep throat, skin infections, and, in rare cases, more serious illnesses such as sepsis or necrotizing fasciitis.

Symptoms of scarlet fever usually appear within 1-2 days of exposure to the bacteria, and may include sore throat, fever, headache, nausea, vomiting, and a red, sandpaper-like rash that starts on the chest and abdomen and spreads to other parts of the body, including the face, neck, and limbs. The rash may be accompanied by a white coating on the tongue, which later peels off, leaving a bright red tongue (known as "strawberry tongue").

Diagnosis of scarlet fever typically involves a medical history, physical examination, and laboratory tests, such as a throat culture or rapid strep test, to confirm the presence of GAS bacteria.

Treatment for scarlet fever usually involves antibiotics, such as penicillin or amoxicillin, to kill the bacteria and prevent complications. Over-the-counter medications, such as acetaminophen or ibuprofen, may also be used to reduce fever and relieve pain.

Prognosis for scarlet fever is generally good with prompt treatment, and most people recover fully without complications. However, in rare cases, scarlet fever can lead to more serious complications, such as rheumatic fever, kidney damage, or pneumonia. If you suspect that you or someone you know may have scarlet fever, seek medical attention promptly for diagnosis and treatment.

Scarlet fever is caused by the same type of bacteria that cause strep throat. In scarlet fever, the bacteria release a toxin that produces the rash and red tongue.

The infection spreads from person to person via droplets expelled when an infected person coughs or sneezes. The incubation period — the time between exposure and illness — is usually two to four days.

There is no vaccine to prevent scarlet fever. The best prevention strategies for scarlet fever are the same as the standard precautions against infections:

• Wash your hands. Show your child how to wash his or her hands thoroughly with warm soapy water.
• Don't share dining utensils or food. As a rule, your child shouldn't share drinking glasses or eating utensils with friends or classmates. This rule applies to sharing food, too.
• Cover your mouth and nose. Tell your child to cover his or her mouth and nose when coughing and sneezing to prevent the potential spread of germs.

If your child has scarlet fever, wash his or her drinking glasses, utensils, and, if possible, toys in hot soapy water or in a dishwasher.

If your child has scarlet fever, your doctor will prescribe an antibiotic. Make sure your child completes the full course of medication. Failure to follow the treatment guidelines may not completely eliminate the infection and will increase your child's risk of developing complications.

Your child can return to school when he or she has taken antibiotics for at least 24 hours and no longer has a fever.