What is scarlet fever?

Scarlet fever is a contagious infection that mostly affects young children. It is easily treated with antibiotics.

Scarlet fever is due to a throat infection caused by a germ called streptococcus. It causes a rough-feeling red rash, sore throat, fever and sometimes other complications.

Scarlet fever is most common in children aged less than 10 years, with 4-year-olds most likely of all to catch it. Although adults can get scarlet fever, this is very unusual. However, the symptoms and treatment are the same as for children.

Symptoms

• High temperature (fever)
• Sore throat and swollen neck glands
• Redness of the tongue with tiny white spots (this occurs around the same time) and sometimes swelling of the tongue a few days later
• A red, rough-feeling rash on their chest, tummy and cheeks - it feels a bit like sandpaper
• If left untreated, the rash and sore throat will fade over about 10 days, but the skin sometimes peels

Not all people with streptococcal infections develop the rash, as some people are not sensitive to the toxin. A mild form of scarlet fever may occur; this is often called scarlatina.

Symptoms are the same for children and adults, although the occurrence of scarlet fever is much rarer in adults.

It is important to see your GP if you or your child:

• Have scarlet fever symptoms
• Do not get better in a week (after seeing a GP), especially if your child has recently had chickenpox
• Are ill again weeks after scarlet fever has cleared up – this can be a sign of a complication, such as rheumatic fever
• Are feeling unwell and have been in contact with someone who has scarlet fever

Scarlet fever is highly contagious. Check with your GP before you go in - they may suggest a phone consultation.

Causes

Sometimes the germ streptococcus only causes a sore throat, without causing the rash of scarlet fever. This is often called a 'strep throat' or simple tonsillitis.

In scarlet fever, the streptococcus bacterium releases toxins that spread through the body. The toxins cause the rash and, if untreated, can cause problems in the kidneys and heart even years later.

Diagnosis

In general the diagnosis can be made on the clinical picture: a child with a high temperature (fever), sore throat, a red tongue and a rough-feeling rash on their chest and tummy.

If there is any doubt as to the diagnosis, a doctor can take a 'throat swab' - using something that looks like a long cotton bud. They will send it to the hospital to be tested for the germ that causes scarlet fever.

The results will take a few days to come back, so if scarlet fever is suspected it's usually best to start the antibiotics first.

A family doctor, or GP, will be able to recognise scarlet fever and should not need blood tests or throat swabs to make the diagnosis.

Treatment

Your GP will prescribe antibiotics. These will:

• Help you get better quicker
• Reduce the risk of serious illnesses, such as pneumonia
• Make it less likely that you'll pass the infection on to someone else

It is vital that you keep taking the antibiotics until they are finished, even if you are feeling better.

The best antibiotic is penicillin, it almost always kills the scarlet fever germ.

You need to take a long course of penicillin: ten days. This is longer than for a simple throat or ear infection and it requires quite a lot of perseverance and organisation to complete the course.

If the child is allergic to penicillin then erythromycin or clarithromycin can be used instead.

You can relieve other symptoms of scarlet fever yourself by:

• Drinking cool fluids
• Eating soft foods if you have a sore throat
• Taking painkillers like paracetamol to bring down a temperature (do not give aspirin to children under 16)
• Using calamine lotion or antihistamine tablets to stop itching

General treatment of a fever

• Keep fluid levels up - water alone is fine but a little bit of sugar will help the water to be absorbed. Dilute squash is fine. In a young child, milk is good too
• If the child is distressed by the fever - for example, they are limp, drowsy or whimpering - it is worth trying paracetamol
• Paracetamol can bring a high temperature (fever) down a little but it does not treat the underlying infection. Note: you should not use paracetamol just to bring down a temperature; it should only be used if the child is really affected by the fever
• Too much paracetamol has been shown to be bad for children because having a mild fever can actually help them to fight off the scarlet fever infection
• Using paracetamol in children or babies does not reduce the risk of febrile convulsions
• Ibuprofen is generally not recommended in infections that involve the skin

Generally antibiotics and fluids are the best treatment for scarlet fever.

Length of illness

Scarlet fever lasts for around a week.

You are infectious up to 7 days before the symptoms start until 24 hours after you take the first antibiotic tablets. People who do not take antibiotics can be infectious for 2 to 3 weeks after symptoms start.

Children with scarlet fever should stay off nursery or school for 24 hours after starting antibiotics or, if not on antibiotics, until their fever is gone.

Complications

Complications are rare. They can happen in the weeks after the infection as well as during it, and can include:

• Ear infection
• Throat abscess
• Sinusitis
• Pneumonia
• Meningitis
• Rheumatic fever

Pregnancy advice

There is no evidence to suggest that getting scarlet fever during pregnancy will harm your baby, but it can make you feel unwell, so it is best to avoid close contact with anyone who has it.

Contact a GP if you do get symptoms. The antibiotics used for scarlet fever are usually safe to take during pregnancy.

Prevention

Scarlet fever is very infectious and can easily spread to other people. To reduce the risk of spreading scarlet fever:

• Wash hands often with soap and warm water
• Use tissues to trap germs from coughs or sneezes
• Bin used tissues as quickly as possible
• Do not share cutlery, cups, towels, clothes, bedding or baths