Scarlet Fever – Causes, Symptons & Treatments
Scarlet fever—or scarlatina—is a bacterial infection that can easily spread to other people. Children and some adults are more likely to get scarlet fever than others. It is usually a mild illness, but it needs to be treated to prevent rare but serious long-term health problems. There is a quick test doctors can use to see if you have scarlet fever. Antibiotics help someone with scarlet fever feel better sooner and protect others from getting sick.
Scarlet fever, or scarlatina as it is called by some people, is caused by bacteria called group A Streptococcus or group A strep. The rash is caused by a poison (toxin) made by the bacteria. It most often occurs along with strep throat, but can also occur with group A strep skin infections.
Spread to Others
Group A strep live in the nose and throat and can easily spread to other people. When someone who is infected coughs or sneezes, the bacteria travel in small droplets of water called respiratory droplets. You can get sick if you breathe in those droplets or if you touch something that has the droplets on it and then touch your mouth or nose. You could also become ill if you drink from the same glass or eat from the same plate as a sick person. It is possible to get scarlet fever from touching sores on the skin caused by group A strep (impetigo).
Although rare, group A strep can be spread through food if it is not handled properly (visit CDC’s food safety page). Pets or household items, like toys, are not known to spread these bacteria.
Signs and Symptoms
In general, scarlet fever is a mild infection. Symptoms of scarlet fever usually include:
- Very red, sore throat
- Fever (101 °F or higher)
- Red rash that has a sandpaper feel
- Bright red skin in the creases of the underarm, elbow, and groin (the area where your stomach meets your thighs)
- Whitish coating on the tongue early in the illness
- “Strawberry” (red and bumpy) tongue
- Swollen glands in the neck
Someone with scarlet fever may also have these more general symptoms:
- Headache or body aches
- Nausea, vomiting, or abdominal pain
It usually takes two to five days for someone exposed to group A strep to become sick. Illness usually begins with a fever and sore throat. One or two days later, a red rash usually appears, although the rash can appear before illness or up to 7 days later. The rash may first appear on the neck, underarm, and groin, then spread over the body. The red 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 finger tips, 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 your 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. Parents of school-aged children and adults who are often in contact with children will have a higher risk for scarlet fever than adults who are not around children very often.
Close contact with another person with scarlet fever is the most common risk factor for illness. For example, if someone has scarlet fever, it often spreads to other people in their household.
Infectious illnesses tend to spread wherever large groups of people gather together. Crowded conditions — such as those in schools, daycare centers, or military training facilities — can increase the risk of getting a group A strep infection.
Diagnosis and Testing
An illness that includes a red rash and sore throat can be caused by many viruses and bacteria. It is very important to determine if group A strep is the cause. A rapid strep test or a throat culture is needed.
A rapid strep test involves swabbing the throat and testing the swab to quickly see if group A strep is causing the illness. If the test is positive, doctors can prescribe antibiotics. If the rapid strep test is negative, but a doctor still strongly suspects scarlet fever, then they can take a throat culture swab to see if bacteria grow from the sample. This culture test requires more time to get the results, but can be important to use in children and teens because they are at risk of getting rheumatic fever if their scarlet fever infection is not treated. For adults, it is usually not necessary to do a throat culture following a negative rapid strep test since there is little risk of adults getting rheumatic fever following scarlet fever.
Scarlet fever is treated with antibiotics (medicine that kills bacteria in the body). Either penicillin or amoxicillin are recommended as a first choice for people who are not allergic to penicillin, but other antibiotics can be used to treat scarlet fever in people who are allergic to penicillin. Antibiotics help shorten how long someone is sick, prevent spreading the disease to others, and prevent getting complications like rheumatic fever.
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, and sinus or ear infections. Other complications can affect the heart (rheumatic fever) or kidneys (post-streptococcal glomerulonephritis).
People can get scarlet fever more than once, so having the infection does not protect you from getting it again in the future. While there is no vaccine to prevent scarlet fever, there are things you can do to protect yourself and others.
The best way to keep from getting or spreading scarlet fever is to wash your hands often, especially after coughing or sneezing and before preparing foods or eating. To practice good hygiene 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. After they have been washed, these items are safe for others to use.
Someone with scarlet fever is usually not able to spread the bacteria to others after they have taken the correct antibiotic for 24 hours or longer. If you are diagnosed with scarlet fever, you should stay home from work, school, or daycare until you no longer have a fever and have taken antibiotics for at least 24 hours so you don’t spread the infection to others.