Scarlet fever causes a sore throat, high temperature and a rash. It usually occurs in children. It has become less serious than it once was. Scarlet fever had become much less common over a period of ten years. However, during September 2013 to March 2014 the number of cases more than doubled.
Full recovery is usual. Treatment is with a course of an antibiotic medicine. It is important to finish the full course of antibiotic, even if symptoms soon go, as this helps to prevent possible complications.
What is scarlet fever?
Scarlet fever is due to a throat infection caused by a germ (bacterium) called streptococcus. There are various types (strains) of streptococcus. They cause different infections and a strain called group A streptococcus causes most instances of scarlet fever.
The scarlet fever rash occurs when the streptococcal bacteria release poisons (toxins) that make the skin go red. The toxins get into the blood from the infected throat. Scarlet fever is most common in children aged under 10 years, the most common age being 4 years.
What are the symptoms of scarlet fever?
- Sore throat and high temperature (fever) are the typical first symptoms.
- A bright red (scarlet) rash then soon develops. The rash starts as small red spots, usually on the neck and upper chest. It may feel like fine sandpaper when you touch it. It soon spreads to many other parts of the body. The face may become quite flushed. The rash goes white (blanches) if you press on it. The areas of skin around the eyes, lips and nose are usually spared from this rash.
- The tongue may become pale but coated with red spots (strawberry tongue). After a few days the whole tongue may look red.
- Other common symptoms include headaches, being sick (vomiting), being off food and feeling generally unwell.
The sore throat and fever last a few days and then usually ease. The rash lasts about six days and then usually fades away. As the rash fades, some of the skin may peel, mainly on the hands and feet (a bit like after being sunburnt). The rash can come back (recur) over the following three weeks though.
However, not all people with streptococcal infections develop the rash, as some people are not sensitive to the poison (toxin). A mild form of scarlet fever may occur; this is often called scarletina.
Are there any tests for scarlet fever?
This condition is usually diagnosed by the symptoms, especially if you have the typical rash.
Sometimes your doctor will take a sample (swab) from your throat to be tested for streptococcus. A blood test is also sometimes done which can confirm that you have this infection.
What is the treatment for scarlet fever?
Treatment is to speed recovery and to prevent possible complications.
A 10-day course of phenoxymethylpenicillin is usually advised. Other antibiotics are advised if you are allergic to penicillins. Symptoms usually improve in a few days but it is important to finish the course of antibiotics. This makes sure all the germs (bacteria) are killed and reduces the chance of complications.
Make your child comfortable
A high temperature (fever) can make a child feel uncomfortable and irritable. The following are things that you can do that may bring the temperature down and make your child feel more comfortable:
- You can give paracetamol or ibuprofen. Both of these medicines can lower a temperature. You can buy these medicines in liquid form for children. They come in various brand names. An alternative is to give soluble paracetamol in a drink. The dose for each age is given with the medicine packet. Note: these medicines do not treat the cause of the fever. They merely help to ease discomfort. You do not need to use these medicines if the child is comfortable and not distressed by the fever.
Note: do not give both paracetamol and ibuprofen at the same time. However, on occasions, if a fever is difficult to control then, for each time a medicine dose is given, a doctor or nurse may advise alternating one of these medicines with the other. It is best only to do this alternating dose regime after assessment by a doctor or nurse.
Note: do not use ibuprofen for:
- Children known to react (have hypersensitivity) to ibuprofen or other non-steroidal anti-inflammatory drugs (NSAIDs).
- Children in whom attacks of asthma have been triggered by an NSAID.
- Children with chickenpox. This is because some research has shown that ibuprofen or other non-steroidal anti-inflammatory drugs (NSAIDs) may increase the risk of developing serious skin infection complications in children with chickenpox.
- Take the clothes off the child if the room is normal room temperature. It is wrong to wrap up a feverish child. The aim is to prevent overheating or shivering.
- Give lots to drink. This helps to prevent lack of fluid in the body (dehydration). You might find that a child is more willing to have a good drink if they are not so irritable. So, if they are not keen to drink, it may help to give some paracetamol or ibuprofen first. Then, try them with drinks half an hour or so later when their temperature is likely to have come down. If breast-feeding then keep breast-feeding, as breast milk is the best fluid. However, you can offer feeds more often to increase the amount of fluid.
Do not cold-sponge a child who has a fever. This used to be popular but it is now not advised. This is because the blood vessels under the skin become narrower (constrict) if the water is too cold. This reduces heat loss and can trap heat in deeper parts of the body. The child may then get worse. Many children also find cold-sponging uncomfortable.
Some people use a fan to cool a child. Again, this may not be a good idea if the fanned air is too cold. However, a gentle flow of air in a room which is room temperature may be helpful. Perhaps just open the window, or use a fan on the other side of the room to keep the air circulating.
What are the possible complications of scarlet fever?
Treatment with antibiotics reduces the chance of complications. Complications now occur very rarely. However, if they do occur, they can be serious.
Complications due to the spread of the infection can occur early in the infection and may include the following:
- Ear infection (otitis media)
- Throat infection and collection of pus (abscess)
- Sinus infection
- Meningitis and brain abscess
Later complications can (rarely) occur a few weeks after the infection has cleared. These occur as a result of immune reactions in the tissues. These may include:
- Rheumatic fever (which can damage the heart)
- Kidney damage (glomerulonephritis)
The recent outbreak of scarlet fever has sometimes occurred in schools where there is also an outbreak of chickenpox. If you have a child who has recently had chickenpox and then gets scarlet fever you need to watch out for signs of serious infection. These may include joint pains, high temperature (fever) and persistent skin infection.
There is no evidence that catching scarlet fever when pregnant will put your baby at risk.
What is the outlook (prognosis) for people with scarlet fever?
In the past, scarlet fever used to be a very serious condition. Fortunately, nowadays for most cases, scarlet fever is a mild, self-limiting illness. Most children will recover fully within a week or so, even without treatment. (However, it is best to have treatment - see above.)
Deaths from scarlet fever are now extremely rare.
Is scarlet fever infectious?
Yes. Coughing, sneezing and breathing out the germs (bacteria) can pass it on (be infectious) to others. Scarlet fever can even be passed on by sharing towels, baths, clothes or bed linen with a person who has been infected.
It takes 2-4 days to develop symptoms after being infected. You should keep children with scarlet fever off school and away from others, for 24 hours after starting antibiotics.
Once a person has had scarlet fever, they are very unlikely to get it again. This is because they become immune to the bacteria. However, it is possible to have repeated (recurrent) attacks, as there are different types of streptococcal bacteria which cause the infection.
Further reading & references
- Scarlet Fever; Public Health England
- Interim guidelines for the public health management of scarlet fever outbreaks in schools, nurseries and other childcare settings; Public Health England, 2014
- Wong S et al; Emerging Microbes and Infections, Nature.com, 2012
- Feverish illness in children - Assessment and initial management in children younger than 5 years; NICE Guideline (May 2013)
- Scarlet fever; NICE CKS, May 2010
- No authors listed; Varicella, herpes zoster and nonsteroidal anti-inflammatory drugs: serious Prescrire Int. 2010 Apr;19(106):72-3.
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.
Dr Tim Kenny
Dr Laurence Knott
Dr Adrian Bonsall