Impetigo is a common and highly contagious skin infection that causes sores and sometimes blisters. It's not usually serious and often improves within a week of treatment. Impetigo can affect people of any age, but it tends to affect children more often than adults.
Symptoms of impetigo
There are two main types of impetigo:
- the most common type is known as non-bullous impetigo, in which blisters are not present
- the less common form, bullous impetigo, in which fluid-filled blisters (bullae) are present
With non-bullous impetigo there are usually no significant symptoms, although there may be some itching.
Other symptoms are uncommon unless the infection is widespread. In bullous impetigo, the area of the blisters tends to be painful and symptoms such as weakness, fever, and diarrhoea are more common.
Since non-bullous impetigo does not usually cause any symptoms, people can easily pass the infection on to others without realising it.
Good hygiene measures are important to help healing and stop the infection spreading to other parts of the body and to other people.
The symptoms of non-bullous and bullous impetigo are described below.
The symptoms of non-bullous impetigo:
- Begin with the appearance of red sores – usually around the nose and mouth but other areas of the face and the limbs can also be affected
- The sores quickly burst leaving behind thick, golden crusts typically around 2cm across - the appearance of these crusts is sometimes likened to cornflakes stuck to the skin
- After the crusts dry, they leave a red mark that usually heals without scarring - the time it takes for the redness to disappear can vary between a few days and a few weeks
- The sores are not painful, but they may be itchy - It's important not to touch, or scratch, the sores because this can spread the infection to other parts of your body, and to other people
Other symptoms, such as a high temperature (fever) and swollen glands, are rare but can occur in more severe cases.
The symptoms of bullous impetigo:
- Begin with the appearance of fluid-filled blisters (bullae) which usually occur on the trunk (the central part of the body between the waist and neck) or on the arms and legs and are usually about 1-2cm across
- The blisters may quickly spread, before bursting after several days - this exposes a raw and painful skin lesion, before forming a leave a yellow crust that usually heals without leaving any scarring
- The blisters may be painful and the area of skin surrounding them may be itchy - as with non-bullous impetigo, it is important that you do not touch or scratch the affected areas of the skin
Symptoms of weakness, fever, diarrhoea and swollen glands are more common in cases of bullous impetigo.
Impetigo usually gets better without treatment in about two to three weeks. However, treatment is often recommended because it can reduce the length of the illness to around seven to 10 days. It can also help lower the risk of the infection being spread to others.
The main treatments prescribed are antibiotic creams or antibiotic tablets. These usually have to be used for about a week.
During treatment, it's important to take precautions to minimise the risk of impetigo spreading to other people or other areas of the body, such as by:
- not touching the sores whenever possible
- washing your hands regularly
- not sharing flannels, sheets or towels
- staying away from work, school, nursery, playgroup or childminders until lesions are crusted and healed, or 48 hours after antibiotic treatment has started
Most people are no longer contagious after 48 hours of treatment or once their sores have dried and healed.
When to seek medical help
If you think you or your child has impetigo, you should see your GP to confirm the diagnosis, and get treatment (for the reasons given above).
Impetigo is not usually serious, but it can sometimes have similar symptoms to more serious conditions such as cellulitis (an infection of the deeper layers of skin) so it's important that it's diagnosed correctly.
Causes of impetigo
Impetigo is caused by bacteria infecting the outer layers of skin.
The bacteria can infect the skin in two main ways:
- through a break in healthy skin, such as a cut, insect bite or other injury
- through skin damaged by another underlying skin condition, such as scabies or eczema
Once someone is infected with the bacteria, the infection can be spread easily through close contact, such as through direct physical contact, or by sharing towels or flannels.
As impetigo is a highly contagious condition, it is important to take precautions to reduce the risk of the infection spreading.
The advice below can help to prevent the spread of the infection to other people or to other areas of the body:
- Stay away from work, school, nursery, playgroup or childminders (or other places where the infection could be spread) until lesions are crusted and healed, or 48 hours after antibiotic treatment has started
- Don't share flannels, sheets or towels with anyone who has impetigo, and wash them at a high temperature after use
- Wash the sores with soap and water, and cover them loosely with a gauze bandage or clothing if possible
- Avoid touching the sores, or letting others touch them, whenever possible
- Don't scratch the affected areas and make sure your or your child's nails are kept clean and short to reduce the risk of further damage caused by scratching
- Avoid contact with new-born babies, preparing food, playing contact sports, or going to the gym until the risk of infection has passed (when the rash has crusted over, or after at least 48 hours of treatment with antibiotics)
- Wash your hands often, particularly after touching infected skin
- Washable toys should also be washed - wipe non-washable soft toys thoroughly with a cloth that has been wrung out in detergent and warm water and allowed to dry completely
- Find out more about impetigo on the NHS website
More useful links
The information on this page has been adapted from original content from the NHS website.
For further information see terms and conditions.