Scarlet fever

Scarlet fever is a bacterial illness which causes a distinctive pink-red rash. It is caused by infection from a bacteria known as haemolytic streptococci, which belong to the streptococcus bacteria group.

Scarlet fever usually follows a sore throat (strep throat) or skin infection (impetigo) caused by particular strains of streptococcus bacteria. The scarlet fever rash occurs when the bacteria release toxins that make the skin go red.

The disease is very contagious. It can be caught by breathing in the bacteria in airborne droplets from an infected person's coughs and sneezes

Scarlet fever is also known as scarlatina, although this sometimes refers to a mild form of the disease.

Nowadays, scarlet fever is rare in Ireland.

What are the symptoms?

The characteristic symptom of scarlet fever is a widespread, fine pink-red rash that feels like sandpaper to touch. It may start in one place, but soon spreads to many parts of the body, such as the ears, neck and chest. It may itch.

The person will develop a flushed, red face, hence the name scarlet fever.

Other symptoms include swollen neck glands, especially if you have a sore throat, and generally feeling unwell

It takes around one to four days to develop symptoms after being infected.

Who is affected?

Anybody can catch scarlet fever, but it usually affects children aged between four and eight. Because it is so contagious, scarlet fever is likely to affect those who are in close contact with someone who has strep throat or a streptococcal skin infection, and those who live in a crowded environment, such as day care.

Most children over 10 will have developed immunity (resistance) to the toxins from streptococcal bacteria and children under two will have acquired immunity from their mothers.

Outlook

Although scarlet fever used to be a very serious disease, most cases today are mild.

Scarlet fever is easily treatable with antibiotics, which must be taken for 10 days. Most people recover after four to five days

There is no evidence that catching scarlet fever when pregnant will put your baby at risk. Pregnant women should inform healthcare staff if they are in contact with streptococcal infections, such as scarlet fever, around the time of their delivery.


Bacteria

Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some others are good for you.

Antibiotics

Antibiotics are medicines that can treat infections caused by micro-organisms, usually bacteria or fungi. Examples include amoxicillin, streptomycin and erythromycin.

It generally takes one to four days after infection for the symptoms of scarlet fever to show. This is known as the incubation period.

The disease often starts with a sore throat or skin infection and fever. The rash appears 12 to 48 hours after the fever.

Rash

The first sign of the rash is red blotches, which turn into a fine pink-red rash that feels like sandpaper to touch and looks like sunburn.

It may start in one place but soon spreads to many other parts of the body, commonly the ears, neck, chest, elbows, inner thighs and groin.

The rash does not normally spread to the face but the cheeks become flushed and the area just around the mouth stays quite pale. The rash will blanche (turn white) if you press a glass on it.

The rash lasts for six days and then usually fades. It may itch and is usually accompanied by other symptoms (see below), although a rash may be the only symptom in milder cases (scarlatina).

Other symptoms

These may include:

  • headache
  • swollen neck glands
  • loss of appetite
  • nausea and/or vomiting
  • stomach pain
  • pastia lines (broken blood vessels in the folds of the body, such as the armpit, causing red streaks that may last a couple of days after the rash has gone)
  • white coating on the tongue, which peels a few days later leaving the tongue looking red and swollen (known as strawberry tongue)
  • a general feeling of being unwell

If you feel very unwell, with severe muscle aches, diarrhoea or vomiting, see your doctor to rule out other infections caused by streptococcal bacteria, such as toxic shock syndrome, which can be easily treated if caught early.

Peeling skin

Outer layers of skin, usually on the hands and feet, may peel for up to six weeks after the rash has faded.


Glossary

Fever
A fever, or high temperature, is when someone's body temperature goes above the normal 37°C (98.6°F).
Nausea
Nausea is when you feel like you are going to be sick.

 

Chickenpox and scarlet fever

If your child has chickenpox and develops a rash that looks like scarlet fever, it may indicate a secondary bacterial infection. Seek medical advice immediately as the secondary infection may prolong the chickenpox or make it more severe

Scarlet fever is contagious and can be caught by:

  • breathing in bacteria in airborne droplets from an infected person's coughs and sneezes
  • touching the skin of a person with a streptococcal skin infection
  • sharing contaminated towels, baths, clothes or bed linen

It can also be spread by people who have the bacteria in their throat but do not show any symptoms (known as carriers). You will only develop the symptoms of scarlet fever if you are susceptible to the toxins released by streptococcal bacteria.



Your GP can usually diagnose scarlet fever by looking at the characteristic rash and other symptoms.

To confirm the diagnosis, a sample of saliva is taken from the back of the throat (throat swab) and tested in a laboratory. This reveals which bacteria have caused the infection. A blood test is sometimes required.

Scarlet fever is a notifiable disease. This means that doctors must report any cases to the local health protection unit so they can monitor the spread of disease.

Glossary

Blood test
A sample of blood is taken from a vein, using a needle, so it can be examined in a laboratory.
Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and others are good for you.
Fever
A fever or high temperature is when someone's body temperature goes above the normal 37°C (98.6°F).

Most mild cases of scarlet fever go away in about a week without treatment.

However, you are advised to get treatment as this will speed recovery. If it is left untreated, the skin may continue to shed for several weeks. There is also a higher risk of complications without treatment

Most people recover around four to five days after starting treatment.

Antibiotics

The most common treatment for scarlet fever is a 10-day course of antibiotics. This will usually be penicillin taken by mouth. For those allergic to penicillin, the antibiotic erythromycin can be used instead.

Stay at home for at least 24 hours after starting treatment (see box to the right).

Symptoms usually go in a few days if the antibiotics are taken properly. The whole course of treatment must be finished to make sure the infection is fully cleared.

The fever will normally disappear within 12 to 24 hours of starting antibiotics.

Other treatments

If you have scarlet fever, drink plenty of cool fluids, especially if you do not have much of an appetite. Keep the room cool.

Paracetamol can also be taken to relieve aches and pains and bring down a high temperature. Calamine lotion can relieve the itch of the rash.


Glossary

High temperature
A high temperature or fever is when someone's body temperature goes above the normal 37°C (98.6°F).
Antibiotic
Antibiotics are medicines that treat infections caused by micro-organisms, usually bacteria or fungi. Examples of antibiotics include amoxicillin, streptomycin and erythromycin.
Allergic
An allergen is a substance that reacts with the body's immune system and causes an allergic reaction.
Aches
An ache is a constant dull pain in part of the body.

How long should I stay at home?

Stay away from school or work for at least 24 hours after starting the antibiotic treatment


Most cases of scarlet fever have no complications. Occasionally, one of the following complications occur:

  • ear infection
  • throat abscess
  • sinusitis
  • kidney inflammation
  • otitis media (build up of fluid in the middle ear)
  • pneumonia
  • rheumatic fever (which causes pain in the joints)

Complications tend to happen only if treatment is unsuccessful or if scarlet fever has not been treated.

Very rare complications include:

  • meningitis
  • acute renal (kidney) failure
  • septicaemia (blood poisoning)
  • necrotising fasciitis (a flesh-eating disease)
  • toxic shock syndrome (a rare, life-threatening bacterial infection)
  • osteomyelitis (infection of the bone and bone marrow)

You may have one of these rare complications if you are very unwell, in severe pain and have severe headache, vomiting or diarrhoea. Look out for any of these symptoms in the first few weeks after the main infection has cleared up.


Glossary

Acute
Acute means occuring suddenly or over a short period of time.
Fever
A fever or high temperature is when someone's body temperature goes above the normal 37°C (98.6°F).
Bone marrow
Bone marrow is the soft, spongy tissue in the centre of bones that produces blood cells.
Inflammation
Inflammation is the body's response to infection, irritation or injury. It causes redness, swelling, pain and sometimes a feeling of heat in the affected area.
Immunity
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Will it recur?

One episode of scarlet fever usually makes you immune (resistant) to further infection. However, recurring attacks happen in rare cases as different forms of streptococcal bacteria can cause the infection

Scarlet fever is highly infectious. It is spread through close physical contact or by contact with the mucous (from coughs or sneezes) from an infected person.

If your child has scarlet fever, do not let them go to school and keep them away from other people until they have been on a course of antibiotics for at least 24 hours.

All tissues and handkerchiefs that someone with scarlet fever has coughed or sneezed into should be washed or disposed of immediately. Wash your hands thoroughly with soap and water if you have touched any of these.

Bacteria can be transmitted by touching someone with a streptococcal skin infection or by sharing contaminated eating utensils, cups and glasses, clothes, baths, bed linen or towels.

Scarlet fever is not common in adults. To avoid catching scarlet fever while you are pregnant and to avoid getting the symptoms, such as high temperature and sore throat, try to keep away from any children who have a suspicious-looking skin rash.

Glossary

Tissues
Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.  
Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and others are good for you.
Fever
A fever or high temperature is when someone's body temperature goes above the normal 37°C (98.6°F).
Antibiotics
Antibiotics are medicines that can be used to treat infections caused by micro-organisms, usually bacteria or fungi. Examples include amoxicillin, streptomycin and erythromycin.

Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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