This factsheet is for people who have impetigo, or who would like information about it including the symptoms, causes and treatments.
Impetigo is a skin infection caused by the bacterium Staphylococcus aureus or Streptococcus pyogenes and causes fluid-filled spots or blisters.
Impetigo usually occurs on your face around your mouth and nose. It’s highly contagious and easily spreads from person to person through touch.
Impetigo is most common in children, particularly under the age of four, but it can also affect older children and adults. Outbreaks of impetigo can happen in areas where there is close contact between people, for example, in schools, nurseries or army barracks.
There are two types of impetigo: bullous and non-bullous.
Bullous impetigo causes fluid-filled spots that don't burst easily and tend to last for a few days. They are usually found on your chest, back and abdomen (tummy) and in folds of skin, such as on your neck or underarm, or on the nappy area in babies.
Non-bullous impetigo is more common and starts with small fluid-filled spots that quickly burst and leave yellow-brown crusts. They usually occur on your face around your nose or mouth, or on your arms or legs.
If impetigo develops in healthy skin it's called primary impetigo. Sometimes impetigo starts in an area of broken skin, for example, at the site of a wound, or an area affected by another condition that breaks the skin, such as eczema, scabies or head lice. This is called secondary impetigo.
If you have impetigo, you will have small fluid-filled spots that are about 1 to 2cm in diameter. However, you will rarely be able to see these because they will quickly burst and then crust over and turn yellow, golden or honey coloured. You may then develop more spots on your skin, close to the initial infection. The spots will eventually dry out and the scabs will fall off to leave red marks, which will gradually disappear – without leaving a scar.
Impetigo can sometimes be itchy and may cause swelling in your lymph nodes (glands throughout your body that are part of your immune system) near the affected area.
Complications of impetigo are uncommon and are more likely to occur if you have bullous impetigo. If impetigo spreads to other areas of your body, you could develop the symptoms listed below.
Impetigo is usually caused by the bacterium S. aureus and less commonly by S. pyogenes.
Impetigo is very contagious and can spread to other people very easily. This can happen either through direct skin-to-skin contact or from sharing towels, face flannels or even bathwater.
The spots or blisters usually appear four to 10 days after you first come into contact with the bacteria.
You’re more likely to develop impetigo if you have:
If you think you or your child has impetigo, see your GP. He or she will ask about your symptoms and examine you. Your GP may also ask you about your medical history.
Your GP will probably diagnose impetigo from examining your skin. However, impetigo can sometimes be confused with other skin conditions, such as shingles, fungal skin infections or cold sores.
If there is any doubt, your GP might take a swab from the affected area. The swab will be tested at a laboratory for the bacteria that typically cause impetigo. Your GP may also need to take a swab if there is an outbreak in your local area, the impetigo keeps coming back, or if he or she thinks that the bacteria causing it is methicillin-resistant staphylococcus aureus (MRSA), for example, if you have been in contact with a person who has been diagnosed with MRSA.
You will normally need antibiotics either as a cream or orally (tablets or syrup) to treat the infection – and to prevent you infecting somebody else.
If only a small area is infected, your GP may prescribe a cream or antiseptic ointment. Your GP will probably prescribe an antibiotic cream called fusidic acid, but there are other antibiotics available. This will clear up most impetigo infections within seven days and you will need to use it two to three times a day. Wash the affected area with warm soapy water before you apply the treatment. If it's not too painful, try to remove crusty areas before you apply the cream or ointment.
Your GP may prescribe you a course of antibiotic tablets for seven days if you have the bullous type of impetigo, the infection doesn't clear or is already or becoming too widespread to use creams or ointments. You may be given flucloxacillin or, if you’re allergic to penicillin, clarithromycin.
If the infection keeps coming back the bacteria responsible may be living in your nose. Your GP may prescribe a nasal ointment, such as mupirocin, to try to clear the bacteria from your nostrils.
It's important that you finish your course of antibiotics. Always ask your GP for advice and read the patient information leaflet that comes with your medicine.
If the impetigo infection doesn't clear up after you have completed your treatment or if your condition worsens, contact your GP.
Impetigo is highly contagious, so it's important to take steps to stop it spreading between family members and other people you come into contact with. If you have impetigo you should follow the steps below.
If the sores are on your fingers or hands, don't prepare any food until two days after you start your treatment.
Don’t go to work (or for children to school or nursery) until your sores have stopped blistering or crusting, or until two days after you start treatment. This is how long it takes for the antibiotic treatment to stop you from being infectious.
If you have damaged skin or a cut, keep it covered with a waterproof dressing. Always wash your hands before and after changing the dressing. Keep any cuts and grazes clean.
Produced by Rebecca Canvin, Bupa Health Information Team, March 2012.
For answers to frequently asked questions on this topic, see FAQs.
For sources and links to further information, see Resources.
This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.
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