Impetigo

Impetigo (impetigo contagiosa) is an itchy and sometimes painful infection of the outer layers of skin. It is especially common in young children. The infection is caused by bacteria. Antibiotics are often used to treat it.

At a glance

  • Impetigo (impetigo contagiosa) is an itchy and sometimes painful infection of the outer layers of skin.
  • It is especially common in young children.
  • The infection is caused by bacteria.
  • The first signs of the condition can usually be seen around the mouth and nose in the form of a rash.
  • In Europe, about 2 out of 100 children are treated for impetigo every year.
  • Antibiotic creams are often used to treat it.

Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.

Impetigo contagiosa: impetigo spots on a boy’s mouth

What is impetigo?

Impetigo is also known as school sores or impetigo contagiosa. Impetigo is an itchy and sometimes painful infection of the outer layers of skin. It is especially common in young children. The infection is caused by bacteria and is highly contagious. For that reason, children who have impetigo aren't allowed to return to school or daycare until they're no longer contagious – about 24 hours after the start of treatment with antibiotics. Without treatment, impetigo can remain contagious for several weeks.

What are the signs of impetigo?

The first signs of impetigo can usually be seen around the mouth and nose in the form of an itchy red rash with water-filled blisters which burst easily and form yellowish crusts. These fall off after some time without scarring.

What causes impetigo?

Impetigo is an infection caused by certain bacteria, usually Streptococcus or Staphylococcus bacteria. These germs can enter the skin in different ways, including through minor cuts or scrapes, a rash or an insect bite.

They spread to other people through skin contact, or through contact with objects that an infected person has touched.

How common is impetigo?

Impetigo contagiosa: roughly 2 out of every 100 children in Europe are treated for impetigo every year.

Impetigo is the most common skin infection in children. In Europe, about 2 out of 100 children are treated for impetigo every year.

How does impetigo develop?

The typical impetigo rash appears a few days after infection, the first signs usually being around the nose and mouth. Impetigo can also spread to the arms, hands and legs. It is rare for impetigo to spread to deeper layers of skin or the nail bed. It generally goes away even without treatment, but it usually takes several weeks. Having had impetigo doesn't make you immune to the bacteria, so you don't have any protection from new infections.

How is impetigo treated?

As long as impetigo doesn't spread beyond a small patch of skin, disinfectant solutions or creams are often recommended. But it isn't clear whether they work.

Antibiotic creams have, however, proven effective. Antibiotics tablets are usually only prescribed if a child has impetigo on a large area of skin or if several parts of their body are affected. Antibiotics that are swallowed are more likely to have side effects than antibiotic creams are. For instance, they may cause gastrointestinal (stomach and bowel) problems.

Good hygiene is important so that those affected don’t infect others. This includes:

  • washing hands frequently.
  • using separate hand towels.
  • washing clothes at a temperature of at least 60 °C.

You can find more detailed information, for example how an impetigo infection can heal more quickly, at gesundheitsinformation.de.

What else is important?

Impetigo is among the infections recorded in the Infectious Diseases Protection Act. This means that even people who only think they might have impetigo should stay away from places where people are gathering to avoid contact with others. Activities with other people are only allowed again once a doctor determines that there is no longer any risk of infecting others. If antibiotics are prescribed, they are usually taken about 24 hours after the start of treatment. Without treatment, impetigo only stops being contagious when it heals by itself.

How is impetigo diagnosed?

Doctors can often tell whether it's impetigo just by looking at it. Further testing on the skin – like a swab test to determine what kind of germs there are – usually isn't needed. But it can help if doctors can't rule out other possible skin diseases, like a fungal infection. 

In cooperation with the Institute for Quality and Efficiency in Health Care (Institut für Qualität und Wirtschaftlichkeit im Gesundheitswesen) (IQWiG). As at:

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