Impetigo is a common and highly contagious skin infection that causes sores and blisters. It's not usually serious and often improves within a week of treatment.
There are two types of impetigo:
- non-bullous impetigo, which typically affects the skin around the nose and mouth, causing sores to develop that quickly burst to leave a yellow-brown crust
- bullous impetigo, which typically affects the trunk (the central part of the body between the waist and neck), causing fluid-filled blisters (bullae) to develop that burst after a few days to leave a yellow crust
Both types of impetigo may leave behind some red marks when the crusts have cleared up, but these will usually improve over the following days or weeks.
Read more about the symptoms of impetigo.
Seeking medical advice
Speak to your GP if you think you or your child may have symptoms of impetigo.
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 to get a correct diagnosis.
Your GP can also prescribe treatment to help clear up the infection more quickly than if it was left untreated.
What causes 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 otherwise 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.
Read more about the causes of impetigo.
Who is affected
Impetigo can affect people of any age, but it tends to affect children more often than adults.
Every year in the UK, around one in every 35 children up to four years of age and around one in every 60 children between four and 15 years of age will develop impetigo.
Non-bullous impetigo is the most common type of impetigo, accounting for more than 70% of cases. Bullous impetigo is most common in babies, although it can affect older children and adults too.
How impetigo is treated
Impetigo usually gets better without treatment in around two to three weeks, but treatment is often recommended because it can reduce the length of the illness to around seven to 10 days and can 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 around 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 or playgroup until the sores have dried up or treatment has been continuing for at least 48 hours
Most people are no longer contagious after 48 hours of treatment or once their sores have dried and healed.
Read more about treating impetigo and preventing the spread of impetigo.
Impetigo is rarely serious, but in some cases the infection can spread to other areas of the body and cause problems such as cellulitis and scarlet fever.
In very rare cases, impetigo may lead to some scarring, particularly if you scratch at the blisters, crusts or sores.
Read more about the possible complications of impetigo.
Page last reviewed: 17/07/2014
Next review due: 17/07/2016