ADAM Health Encyclopedia

Scarlet fever

Definition

Scarlet fever is a disease caused by an infection of the throat with group A beta-hemolytic streptococcal bacteria (strep throat).

Alternative Names

Causes

Scarlet fever was once a very serious childhood disease, but now is easily treatable. The time between becoming infected and having symptoms is short, generally 1 - 2 days. Illness typically begins with a fever and sore throat. It may be accompanied by chills, vomiting, abdominal pain, and malaise.

The streptococcal bacteria produces a toxin that causes a rash to appear 1 - 2 days after the onset of illness. The rash usually first appears on the neck and chest, then spreads over the body. It is described as "sandpapery" in quality. The texture of the rash is more important than the appearance in confirming the diagnosis. The rash can last for over a week. As the rash fades, peeling (desquamation) may occur around the finger tips, toes, and groin area.

The main risk factors is infection with the bacteria that causes strep throat. A history of strep throat or scarlet fever in the community, neighborhood, or school may increase the risk of infection.

Symptoms

• Sore throat
• Fever
• Vomiting
• Rash on neck and chest; rough "sandpaper" feel to the skin
• Peeling (desquamation) of the finger tips, toes, and groin
• Swollen, red tongue (strawberry tongue)
• Pastia's lines (bright red color in the creases of the underarm and groin)
• Chills
• Headache
• Generalized discomfort (malaise)
• Abdominal pain
• Muscle aches

Exams and Tests

• Physical examination
• Throat culture positive for Group A Strep
• Rapid antigen detection (throat swab)

Treatment

Antibiotics are used to kill the bacteria that causes the throat infection. This is crucial to prevent rheumatic fever, the most feared complication of strep throat and scarlet fever.

Outlook (Prognosis)

With proper antibiotic treatment, the symptoms of scarlet fever should resolve quickly (though the rash can last for up to 2 - 3 weeks before it is fully resolved).

Possible Complications

Complications are rare with proper treatment. These can include:

• Acute rheumatic fever
• Ear infection (otitis media)
• Adenitis or abscess
• Pneumonia
• Sinusitis
• Meningitis
• Bone or joint problems (osteomyelitis or arthritis)
• Liver damage (hepatitis)
• Kidney damage (glomerulonephritis)

When to Contact a Medical Professional

Call your health care provider if symptoms of scarlet fever develop, if symptoms do not subside 24 hours after beginning antibiotic treatment, or if new symptoms develop.

Prevention

Bacteria are spread by direct contact with infected persons or by droplets exhaled by an infected person. Avoid contact with infected persons.