Scarlet fever, sometimes called scarlatina, is an infectious disease caused by a type of bacteria called Streptococcus pyogenes or group A streptococcus (GAS). The same bacteria can also cause impetigo.These bacteria are commonly found on the skin or in the throat, where they can live without causing problems. Under some circumstances, however, these bacteria can cause disease.
Scarlet fever (sometimes called scarlatina) is an infectious disease caused by bacteria called Streptococcus pyogenes, or group A streptococcus (GAS). The same bacteria can also cause impetigo. These bacteria are commonly found on the skin or in the throat, where they can live without causing problems. However, under some circumstances, they can also cause diseases, like scarlet fever.
Scarlet fever is characterised by a rash, which usually accompanies a sore throat, and is sometimes confused with the measles' rash. The bacteria which cause the infection produce toxins (poisons), which cause a rash, a red and swollen tongue and flushed cheeks.
Scarlet fever is mainly a childhood disease and is most common between the ages of two and eight years. It was once dangerous, but antibiotic treatment means it is now much less common and much less serious, although 2-4,000 cases are diagnosed each year in England.
It is still highly contagious. The bacteria are carried in the saliva and mucus in the nose. The disease is spread by sneezing, coughing, or breathing out. It can also be caught by direct contact with the mucus or saliva of an infected person. It takes around two to five days to develop symptoms after being infected. If you think your child has scarlet fever, you should consult your GP.
The disease tends to be most common in the winter and spring and the usual treatment is a 10-day course of antibiotics.
Scarlet fever is spread via the mucus and saliva of infected people. It can also be caught from any drinking glasses, plates or utensils they have used. To protect yourself from getting the illness you should:
If you think you, or your child, have scarlet fever:
It usually takes two to five days from infection before the first symptoms appear. However, the incubation period may be as short as one day and as long as seven days.
Scarlet fever usually clears up after a week, but it is advisable to visit your GP to get a full diagnosis and proper treatment.
Scarlet fever is highly contagious. The bacteria are present in the mouth, throat and nose of the infected person and are spread by contact with that person's mucus or saliva. These might even be on cups, plates, pens, or surfaces, such as tables which might have been used or touched by someone carrying the bacteria.
You can also catch the disease by breathing infected airborne droplets produced through an infected person's coughing or sneezing.
Scarlet fever is mainly a childhood disease, with around 80% of cases occurring in children under 10 years old. It is most common in children between the ages of two and eight years, with four-year-olds most likely to develop the illness. Occasionally, outbreaks of scarlet fever occur in nurseries and schools. Adults of all ages can also catch scarlet fever, but the disease is much less common in adults.
Most mild cases of scarlet fever will clear up on their own, but it is still best to see your GP if you, or your child, are showing symptoms. Having treatment for the illness speeds recovery and reduces the risk of complications. You will also become non-contagious more quickly.
In most cases, doctors can diagnose scarlet fever from the symptoms alone. The diagnosis can be confirmed by taking a throat swab, which is then sent to a laboratory to identify the bacteria causing the infection. In some cases, a throat swab is not enough and a blood test may be needed.
The usual treatment for scarlet fever is a 10-day course of antibiotics. The fever will usually subside within 24 hours of starting this, but it is important to take the whole course to clear the infection.
If scarlet fever is not treated with antibiotics, it can be infectious for two to three weeks after the symptoms appear. Provided all prescribed antibiotics are taken as directed, most cases will not infect other people after 24 hours of treatment. Current guidance advises that children should not return to nursery or school and adults to work until a minimum of 24 hours after starting treatment.
If you have a high temperature you should drink plenty of fluids. You can also take paracetamol to bring down your temperature and relieve discomfort.
Once you have had scarlet fever you are unlikely to get it again.
Most cases of scarlet fever have no complications at all. However, in the early stages, there is a small risk that you might get one of the following:
On rare occasions, at a later stage the disease could lead to:
Patients, or their parents, should keep an eye out for any symptoms which might suggest these complications in the first few weeks after the main infection has cleared up and, if concerned, seek medical help immediately.
The Health Protection Agency provides advice on controlling scarlet fever outbreaks and tries to reduce the number of people infected. The agency undertakes continuous monitoring to detect changes in the numbers and types of people diagnosed with scarlet fever, or changes in the characteristics of strains causing scarlet fever.
The Health Protection Agency is an independent organisation, set up by the government to protect the public from the effects of infectious diseases and other hazards to health. The agency identifies, researches and responds to these threats. It gives advice to the public on how to avoid harm, provides data and information to government, and advises people working in healthcare.
If you have concerns about your health contact NHS Direct on 0845 4647 or visit their website www.nhsdirect.nhs.uk, or see your family doctor.
Reviewed: 21 April 2010
Did you know ...?
Although scarlet fever is now a mild and uncommon disease, 100 years ago severe scarlet fever epidemics in which many people died were common.
Antibiotics have greatly reduced the severity of the disease, although it was already becoming less severe before they were available. We don't know why this is, but one theory is that the strain of bacteria that cause scarlet fever has become weaker over time.