What Is Scarlet Fever? What Causes Scarlet Fever?

Scarlet fever, also known as scarlatina, is a disease caused by a toxin (erythrogenic exotoxin) released by Streptococcus pyogenes or group A beta-hemolytic streptococcus - the disease occurs in a small percentage of patients with strep infections, such as strep throat or impetigo. Although scarlatina may be used interchangeably with scarlet fever, scarlatina is more commonly used to refer to the less acute form of scarlet fever.

The bacterial illness, scarlet fever, causes a distinctive pink-red rash, which occurs when the bacteria release toxins.

Scarlet fever is extremely contagious - people can catch it by breathing in the bacteria in airborne droplets that come from an infected individual's sneezes or coughs. Infection may also occur as a result of touching the skin of an infected person, or touching surfaces or objects that the infected person has touched.

Scarlet fever is rare these days, mainly because antibiotics are used to treat strep infections.

Scarlet fever is much more common among children aged 5 to 15 years than other people. It used to be considered a serious childhood illness. However, modern antibiotics have made it a much less threatening disease. If left untreated scarlet fever can sometimes lead to serious conditions that affect human organs, including the heart and kidneys.

According to Medilexicon's medical dictionary:

Scarlet fever or Scarlatina is "An acute exanthematous disease, caused by infection with streptococcal organisms producing an erythrogenic toxin, marked by fever and other constitutional disturbances, and a generalized eruption of closely aggregated bright red points or small macules followed by desquamation in large scales, shreds, or sheets; mucous membrane of the mouth and fauces is usually also involved."

What are the signs and symptoms of scarlet fever?

A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign.

Signs and symptoms generally appear about one to four days after initial infection. The first symptoms are usually:

• A very sore and red throat (sometimes with white or yellowish patches).


• A fever of 101 F (38.3 C) or higher, frequently with chills. 12 to 48 hours later the rash will appear.


• Rash - red blotches appear on the skin; they then turn into a fine pink-red rash that looks like sunburn. The skin feels rough, like sandpaper, when touched.
  
  The rash spreads to the ears, neck, elbows, inner thighs and groin, chest and some other parts of the body. Although the rash does not usually appear on the face, the patient's cheeks will become flushed and the area around his/her mouth appear pale.
  
  If a glass is pressed on the skin the rash will turn white (blanche).
  
  After about six days the rash usually fades. In milder cases, such as scarlatina, the rash may be the only symptom.

Scarlet fever may also have the following signs and symptoms:

• Difficulty swallowing
• General malaise
• Headache
• Itching
• Loss of appetite
• Nausea
• Pastia's lines - broken blood vessels in the folds of the body, for example the armpits, groin, elbows, knees and neck.
• Stomachache
• Swollen neck glands (lymph nodes) that are tender to the touch
• Tongue - a white coating forms on the tongue. This eventually peels away leaving a strawberry tongue; the tongue is red and swollen.
• Vomiting

If the patients has other symptoms, such as severe muscle aches, vomiting or diarrhea the doctor will have to rule out other possible causes, such as toxic shock syndrome.

The skin of the hands and feet will usually peel for up to six weeks after the rash has gone.

What are the risk factors for scarlet fever?

A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesity significantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2.

• Children - aged from 5 to 15 years have a higher risk of developing scarlet fever compared to other people.
• Close contact - the strep bacteria can spread more easily among people in close contact. If somebody in the household carries the bacteria, infection may spread more readily among household members (and colleagues at school).

What causes scarlet fever?

Scarlet fever is caused by a bacterium called Streptococcus pyogenes, or group A beta-hemolytic streptococcus. This is the same bacterium that causes strep throat. When the bacteria release toxins scarlet fever symptoms occur, including the rash, Pastia's lines, red tongue and flushed face.

Scarlet fever transmits from human-to-human by fluids from the mouth and nose. When an infected individual coughs or sneezes the bacteria become airborne in droplets of water and can be inhaled. The bacteria may land on surfaces, such as drinking glasses, work surfaces and doorknobs and infect people who touch them with their hands and then touch their own nose or mouth. The bacteria may also be inhaled.

If you touch the skin of an individual with a streptococcal skin infection there is a risk of becoming infected.

People who share towels, baths, clothes or bed linen with an infected person risk becoming infected themselves.

A person with scarlet fever who is not treated may be contagious for several weeks, even after symptoms have gone. It is also possible for somebody to carry the infection and be contagious, even though they never had any symptoms - only people who are susceptible to the toxins released by streptococcal bacteria develop symptoms. These factors make it harder for individuals to know whether they have been exposed.

Although much less common, people may become infected by touching or consuming contaminated food, especially milk.

Other types strains of Streptococcus pyogenes linked to either skin infections, such as impetigo, or uterine infections that may occur during childbirth may also cause scarlet fever - however, this is much rarer.

Diagnosing scarlet fever

The characteristic rash and symptoms usually make it fairly easy for a doctor to diagnosis scarlet fever. The doctor may take a throat swab in order to determine which bacteria caused the infection. Sometimes a blood test is also ordered.

Rapid DNA test - a throat swab is taken. Results are returned within a day at the most.

In the United Kingdom and many other countries scarlet fever is a notifiable disease. This means that any confirmed cases must be reported to local health authorities.

What are the treatment options for scarlet fever?

According to the National Health Service (NHS), UK, the majority of mild cases of scarlet fever resolve themselves within a week without treatment. The NHS advises people to get treatment anyway, as this will accelerate recovery and reduce the risk of complications. Patients generally recover about four to five days after treatment begins.

Antibiotics - a 10-day course of antibiotics is the most common treatment for scarlet fever. In the UK, and many other countries this involves taking oral penicillin. Patients who are allergic to penicillin may take erythromycin instead. Patients are advised to stay at home during the course of the antibiotic treatment.

The fever will usually go away within 12 to 24 hours of taking the first antibiotic medication.

According to the Mayo Clinic, USA, a child with scarlet fever may be prescribed one of the following antibiotics:

• Penicillin, in pill form or by injection
• Amoxicillin (Amoxil, Trimox)
• Azithromycin (Zithromax)
• Clarithromycin (clarithromycin extended-release tablets). External link" target="_blank">Biaxin)
• Clindamycin (clindamycin phosphate). External link" target="_blank">Cleocin)
• A cephalosporin such as cephalexin (Keflex)

It is important to complete the full course of antibiotics, even if symptoms go away before it is finished. Otherwise, the infection may not be completely eradicated, raising the risk of subsequent post-strep disorders.

If the patient does not start feeling better within 24 to 48 hours after starting the antibiotic treatment, call the doctor.

Within 24 hours of starting the antibiotics the patient will no longer be contagious.

Other treatments - it is important to drink plenty of liquids, especially if there is no appetite. The room should be kept cool.

Tylenol (paracetamol) may help relieve aches and pains, as well as bringing the fever down.

Calamine lotion may help with itchy skin.

What are the possible complications of scarlet fever?

In the majority of cases there are no complications. If any occur, they may include:

• Ear infection, including otitis media
• Pneumonia
• Throat abscess - a pus-filled sac in the throat
• Sinusitis
• Inflammation of the kidney(s) - poststreptococcal glomerulonephritis, resulting from certain byproducts of strep bacteria. In some cases there may be long-term kidney disease.
• Rheumatic fever
• Some skin infections

The following complications are possible, but very rare:

• Acute kidney (renal) failure
• Meningitis - inflammation of the membranes and fluid that surround the brain and spinal cord.
• Necrotizing fasciitis - commonly known as flesh-eating disease
• Toxic shock syndrome
• Endocarditis - infection of the heart's inner lining
• Infection of the bone and bone marrow (osteomyelitis)
• PANDAS (Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections) - according to the Mayo Clinic, USA, some research has indicated that strep bacterial infection may trigger an autoimmune response that exacerbates symptoms of certain childhood disorders, such as OCD (obsessive-compulsive disorder), Tourette syndrome and ADHD (attention deficit hyperactivity disorder). The increase in symptoms does not usually last for more than a few weeks or months.

Scarlet fever prevention

The best prevention strategies for scarlet fever, as with all highly infectious diseases, are:

• Isolation - keep the patient away from other people. Keep the child away from school.
• Handkerchiefs or tissues that the patient has used should be washed or disposed of immediately. If you have touched any of these wash your hands thoroughly with warm water and soap.
• Handwashing - the patient, usually a child, should be taught to wash his/her hands thoroughly and frequently.
• Dining utensils - do not share drinking glasses or eating utensils with the patient.
• Coughing and sneezing - the patient should be taught to cover his/her mouth and nose when coughing and sneezing. This should be done into a tissue or handkerchief. If one is not available it is better to cough/sneeze into the inside of the elbow - coughing into one's hands raises the risk of contaminating things when they are touched.