Impetigo explained

What impetigo is

Impetigo is a skin infection caused by bacteria, usually Staphylococcus aureus and sometimes Streptococcus. These bacteria live harmlessly on many people's skin but can cause infection when they get into a break, such as a cut, insect bite, graze, or a patch of eczema. There are two main forms. Non-bullous impetigo, the more common type, produces sores that quickly crust over with a golden colour. Bullous impetigo causes larger fluid-filled blisters that last longer before bursting. Impetigo is most common in warm weather and in young children, partly because they are more likely to have minor skin breaks and close contact with others. It is usually a surface infection and, treated properly, heals without scarring.

How to recognise it

Impetigo often begins as small red spots or blisters, commonly around the nose and mouth but possible anywhere, including the hands and limbs. The blisters soon burst, leaving moist, weeping patches that dry into the classic honey-coloured or golden-brown crusts. The sores may itch but are not usually painful, and the person is often otherwise well. In the bullous form, larger blisters filled with clear or cloudy fluid appear, sometimes on the trunk, and can leave shallow, raw areas when they break. Because scratching spreads the bacteria to new areas and to other people, fresh patches can appear nearby. The typical appearance usually makes the diagnosis clear, though occasionally a swab is taken if the picture is unusual or treatment is not working.

How it spreads

Impetigo is very contagious. It spreads through direct skin-to-skin contact and by touching contaminated items such as towels, flannels, bedding, clothing, and toys. Scratching an itchy sore transfers bacteria onto the fingers, which then seed new patches on the same person or pass the infection to others. This easy spread is why outbreaks can occur in households, nurseries, and schools, and why hygiene is central to management. A person is generally considered infectious until the sores have crusted and dried over, or until they have had antibiotic treatment for a couple of days. Covering the affected skin where practical, not sharing personal items, and washing hands after touching the sores all help limit spread while the infection clears.

Treatment through pharmacy and GP

Mild, localised impetigo can often be managed with help from a community pharmacist, who may recommend an antiseptic or, in England, supply a topical antibiotic through the pharmacy first service for suitable patients. Treatment usually involves cleaning the crusts gently and applying a prescribed antibiotic cream. More widespread infection, or cases that do not improve, may need antibiotic tablets or liquid from a GP. It is important to complete the full course and to keep using good hygiene alongside treatment. With appropriate treatment, impetigo typically starts to improve within a few days and clears within a week or so. If sores spread despite treatment, keep recurring, or the person becomes feverish or unwell, a further GP review is needed to reassess.

Hygiene and school advice

Stopping impetigo spreading is as important as treating it. Wash hands often, especially after touching the sores or applying cream, and try to stop children scratching by keeping nails short and covering the affected skin where possible. Do not share towels, flannels, bedding, or clothing, and wash these at a hot temperature. Clean toys and surfaces that may be contaminated. In the UK, children and adults with impetigo should stay away from school, nursery, or work until the sores have crusted and healed over, or until they have had antibiotic treatment for 48 hours, whichever is sooner. Following this advice protects others and helps bring outbreaks in families and schools under control quickly.