Increase in Invasive Group A Strep Infections, 2022–2023
CDC is looking into an increase in invasive group A strep (iGAS) infections among children in the United States. iGAS infections include necrotizing fasciitis and streptococcal toxic shock syndrome.
Scarlet Fever: All You Need to Know
If your child has a sore throat and a rash, it may be scarlet fever (also called scarlatina). Your child’s doctor can do a quick strep test to find out.
If your child has scarlet fever, antibiotics can help your child feel better faster and prevent long-term health problems. Antibiotics can also help protect others from getting sick.
Bacteria called group A Streptococcus (group A strep) cause scarlet fever. These bacteria are also the cause of strep throat. The bacteria sometimes make a toxin (poison), which causes a rash — the “scarlet” of scarlet fever.
Group A strep bacteria are very contagious. Generally, people spread the bacteria to others through
- Respiratory droplets
- Direct contact
Rarely, people can spread group A strep bacteria through food that is not handled properly (visit CDC’s food safety page).
It usually takes two to five days for someone exposed to group A strep bacteria to become sick with strep throat or scarlet fever.
Group A strep bacteria often live in the nose and throat. People who are infected spread the bacteria by talking, coughing, or sneezing, which creates respiratory droplets that contain the bacteria.
People can get sick if they:
- Breathe in respiratory droplets that contain the bacteria
- Touch something with those droplets on it and then touch their mouth or nose
- Drink from the same glass or eat from the same plate as a person infected with group A strep
People can also spread group A strep bacteria from infected sores on their skin. Other people can get sick if they:
- Touch sores on the skin caused by group A strep (impetigo) or come into contact with fluid from the sores
It is important to know that some infected people do not have symptoms or seem sick. People sick with scarlet fever are much more contagious than those who do not have symptoms.
In general, scarlet fever is a mild infection. Illness usually begins with a fever and sore throat. Swallowing may be painful.
- Very red, sore throat
- Fever (101°F or higher) or chills
- Whitish coating on the tongue early in the illness
- “Strawberry” (red and bumpy) tongue
- Red skin rash that has a sandpaper feel
- Bright red skin in the creases of the underarm, elbow, and groin
- Swollen glands in the neck
Other general symptoms:
- Headache or body aches
- Nausea, vomiting, or abdominal pain
One to 2 days after the illness begins, a red rash usually appears. However, the rash can appear before illness or up to 7 days later.
The rash may first appear on the neck, underarm, and groin (the area where your stomach meets your thighs). Over time, the rash spreads over the body. The rash usually begins as small, flat blotches that slowly become fine bumps that feel like sandpaper.
Although the cheeks might look flushed (rosy), there may be a pale area around the mouth. Underarm, elbow, and groin skin creases may become brighter red than the rest of the rash.
The rash from scarlet fever fades in about 7 days. As the rash fades, the skin may peel around the fingertips, toes, and groin area. This peeling can last up to several weeks.
Anyone can get scarlet fever, but there are some factors that can increase the risk of getting this infection.
Scarlet fever, like strep throat, is more common in children than adults. It is most common in children 5 through 15 years old. It is rare in children younger than 3 years old. Adults who are at increased risk for scarlet fever include:
- Parents of school-aged children
- Adults who are often in contact with children
Close contact with another person with scarlet fever is the most common risk factor for illness. For example, if someone has scarlet fever, the bacteria often spread to other people in their household.
Infectious illnesses tend to spread wherever large groups of people gather. Crowded settings can increase the risk of getting a group A strep infection. These settings include:
- Daycare centers
- Military training facilities
Many viruses and bacteria can cause an illness that includes a red rash and sore throat. A doctor will determine what type of illness you have by asking about symptoms and doing a physical exam. If they think you might have scarlet fever, they will swab your throat to test for strep throat. There are two types of tests for strep throat: a rapid strep test and throat culture.
Rapid strep test
A rapid strep test involves swabbing the throat and running a test on the swab. The test quickly shows if group A strep bacteria are causing the illness.
- If the test is positive, doctors can prescribe antibiotics.
- If the test is negative, but a doctor still suspects scarlet fever, then the doctor can take a throat culture swab.
A throat culture takes time to see if group A strep bacteria grow from the swab. While it takes more time, a throat culture sometimes finds infections that the rapid strep test misses.
Culture is important to use in children and teens since they can get rheumatic fever from an untreated scarlet fever infection. For adults, it is usually not necessary to do a throat culture following a negative rapid strep test. Adults are generally not at risk of getting rheumatic fever following scarlet fever.
Doctors treat scarlet fever with antibiotics. Benefits of antibiotics include:
- Decreasing how long someone is sick
- Decreasing symptoms (feeling better)
- Preventing the bacteria from spreading to others
- Preventing serious complications like rheumatic fever
When to return to work, school after illness
People with scarlet fever should stay home from work, school, or daycare until they:
- No longer have a fever
- Have taken antibiotics for at least 12 hours
Antibiotic dos and don’ts
- Do take the prescription exactly as the doctor says to.
- Don’t stop taking the medicine, even if you or your child feels better, unless the doctor says to stop.
You can find more guidance on taking antibiotics on CDC’s Antibiotic Do’s & Don’ts Page.
Complications can occur after having scarlet fever. This can happen if the bacteria spread to other parts of the body. Complications can include:
- Abscesses (pockets of pus) around the tonsils
- Swollen lymph nodes in the neck
- Ear, sinus, and skin infections
- Pneumonia (lung infection)
- Rheumatic fever (a disease that can affect the heart, joints, brain, and skin)
- Post-streptococcal glomerulonephritis (a kidney disease)
- Arthritis (joint inflammation)
Treatment with antibiotics can prevent most of these health problems.
People can get scarlet fever more than once. Having scarlet fever does not protect someone from getting it again in the future. While there is no vaccine to prevent scarlet fever, there are things people can do to protect themselves and others.
To prevent group A strep infections, you should:
- Cover your mouth and nose with a tissue when you cough or sneeze.
- Put your used tissue in the waste basket.
- Cough or sneeze into your upper sleeve or elbow, not your hands, if you don’t have a tissue.
- Wash your hands often with soap and water for at least 20 seconds.
- Use an alcohol-based hand rub if soap and water are not available.
You should also wash glasses, utensils, and plates after someone who is sick uses them. These items are safe for others to use once washed.
Antibiotics help prevent someone with scarlet fever from spreading the bacteria to others.