People get scarlet fever from a bacterium called group A Streptococcus, which is also known as group A strep. This bacterium can sometimes release a poison that causes a rash. The illness gets its name from the resulting rash, which can be scarlet colored.
Group A strep bacteria usually live in the nose and throat, and they can spread when a person with the infection coughs or sneezes. People can get scarlet fever by breathing in these droplets. They can also get it from touching a contaminated surface, drinking from the same glass as someone with the infection, or touching sores that group A strep has caused.
Keep reading to learn more about scarlet fever rash, including what it looks like and how to treat it.
A few days after a person gets sick with group A strep, a rash usually appears. Some people may notice a rash before they develop a fever or sore throat, while others may not see a rash until 7 days after the first appearance of other symptoms.
The rash may first appear on the neck, underarm, and groin, but in time, it can spread across the whole body. At first, the rash appears as small, flat blotches, but these slowly become fine bumps that feel like sandpaper. The skin around the mouth may turn paler, while the cheeks appear flushed.
In people with lighter skin, the creases of the underarm, elbow, and groin may also turn bright red.
It can be more difficult to see scarlet fever rash on darker skin, but it will still have the characteristic sandpaper-like texture.
After about 7 days, the rash usually disappears. When the rash begins to fade, the skin around the fingertips, toes, and groin may peel. Peeling can last several weeks.
Although anyone can get scarlet fever, some people are more prone to it.
Scarlet fever is more common in children aged 5–15 years. Some adults at risk of scarlet fever include parents and caregivers of school-aged children and adults who are in contact with children — for example, day care providers, teachers, and other family members.
Crowded areas, such as schools, day care centers, and military training centers, can increase the risk of infection.
The typical presentation of scarlet fever is:
- high fever
- red and sore throat
- strawberry tongue
- sandpaper-like rash
Other symptoms may include:
- painful swallowing
The rash typically appears 2–3 days after infection, but it can take up to 7 days to develop. The rash usually begins on the trunk, underarms, and groin before spreading to the limbs. After some time, it starts to flake on the palms of the hands and soles of the feet.
Scarlet fever tends to surge at the start of the school year and in the winter months. At these times, doctors should take extra care when reviewing fever and rash symptoms of children between 5 and 15 years of age.
Some viral illnesses, such as measles, chickenpox, and hand, foot, and mouth disease, may have similar presentations to scarlet fever. However, they have specific characteristics that help doctors distinguish them.
- abscesses around the tonsils
- swollen lymph nodes in the neck
- ear, sinus, and skin infections
- rheumatic fever
- poststreptococcal glomerulonephritis
Taking antibiotics early in the infection can prevent these complications.
There is no vaccine to prevent scarlet fever, and some people can get it more than once, though this is uncommon. The best way to control the spread of group A strep is to practice good hygiene. Hand washing is an effective strategy to prevent the spread of scarlet fever, especially after coughing or sneezing into the hand.
Scarlet fever is a mild illness. People with scarlet fever usually require antibiotics because there is a chance that the infection could spread to other parts of the body and cause more severe issues. If a person decides not to take antibiotics, they may be contagious for up to 3 weeks.
Penicillin and amoxicillin are the recommended first-line treatments. For those with a penicillin allergy, cephalosporins may help. After about 24 hours of taking antibiotics, the person is no longer contagious and may notice an improvement in their symptoms.
Some people may also take over-the-counter drugs, such as acetaminophen and ibuprofen, for fever and sore throat symptoms. Fluid replacement also helps people with fever. Scarlet fever rash is usually not itchy and does not require topical treatments.
People with scarlet fever require medical attention. Anyone who experiences fever and a rash should see a doctor immediately. As scarlet fever can resemble other infectious diseases, a correct diagnosis is essential.
Scarlet fever requires prescription antibiotics. Anyone experiencing complications of scarlet fever, even while on antibiotics, should speak with a doctor. Some strains of group A strep are resistant to some antibiotics.
Scarlet fever rash is a symptom of scarlet fever. Other symptoms include a sore throat and fever.
Children, and adults in frequent contact with children, are most at risk of getting scarlet fever. It is a very contagious infection that usually spreads through respiratory secretions from coughing and sneezing.
Doctors treat scarlet fever with antibiotics. Taking antibiotics can help control the spread of scarlet fever and prevent complications.