What should you know about hair impetigo?

Small red spots may become fluid-filled blisters or shallow open sores. After they break, a sticky yellow-brown crust can form on the scalp or along the hairline. Itching may lead to scratching and spread the infection to nearby skin. Hair itself is not infected, although crust can cling to strands and make washing uncomfortable. Eczema or other irritated skin can provide a route for bacteria to enter; see Atopic Dermatitis for context. Crusting Skin describes the visible change in more detail.

Arrange a medical review, especially when sores are spreading, tender, draining or close to the eyes. Wash hands after touching the scalp, avoid sharing towels, brushes, hats or pillowcases, and launder items that contact the affected area. Do not pick crusts or scrape the scalp. A clinician may recommend a prescribed medicine applied to the skin; Topical Antibiotic Therapy explains this option. More extensive infection may need medicine taken by mouth, described under Antibiotics For Skin Infection. Keep nails short to reduce skin damage from scratching.

Seek prompt care if redness, warmth, swelling or pain is expanding, if fever or marked tiredness develops, or if the scalp becomes difficult to touch. Urgent assessment is sensible for swelling around an eye, facial weakness, confusion, or difficulty drinking. A child with rapidly spreading sores should be kept away from close-contact activities until a clinician advises that returning is appropriate.

Could this be impetigo or another scalp infection? Do I need a skin swab? Which treatment should reach the scalp beneath the hair, and how should crusts be softened? When can school, work, sport or close family contact safely resume?