Overview
Lice are tiny parasitic insects that live on the scalp (head lice), body (body lice), or pubic area (pubic lice/crabs). Head lice are most common, affecting school-age children. They spread by direct head-to-head contact. They do not indicate poor hygiene. All types are treatable with insecticide lotions or physical removal methods.
How common is it?
Head lice affect millions of children annually. In the UK, 1 in 3 school children will have head lice at some point. They are equally common in clean and unwashed hair. Pubic lice affect about 2% of adults at some point.
Causes and risk factors
Lice are spread directly from person to person. Head lice cannot jump or fly; they transfer by prolonged head-to-head contact.
Common risk factors
- Direct head-to-head contact (most important route)
- Shared combs, hairbrushes, or hats (less commonly)
- School and household contact with infected individuals
- Pubic lice: close physical and sexual contact
- Body lice: poor hygiene conditions, overcrowding, homelessness
Symptoms
- Itching of the scalp, particularly behind the ears and at the nape of the neck
- Sensation of something moving in the hair
- Seeing lice eggs (nits): white, teardrop-shaped cases firmly stuck to hair shafts close to the scalp
- Sores on the scalp from scratching
- Pubic lice: intense itching in pubic area, visible nits in pubic hair
When to see a doctor
Lice can usually be treated at home without seeing a doctor. See a GP if treatment has failed after two or three courses, if there are signs of secondary skin infection from scratching, or if pubic lice are present (STI screening recommended).
Diagnosis
Wet combing with a fine-toothed nit comb after applying conditioner is the most reliable detection method. A live moving louse confirms active infestation. Nits alone do not prove active infestation.
Treatments
Insecticide lotions
Dimeticone 4% lotion (physical suffocation, no resistance) or malathion 0.5% lotion (chemical). Apply to dry hair, leave for the required time, then wash off. Repeat in 7 days to kill newly hatched lice.
Wet combing
Condition the hair and systematically comb through with a nit comb every 3 to 4 days for 2 weeks. Effective without chemicals and preferred for young children and in pregnancy.
Electric combs
Electronic combs (Robi Comb) kill lice with an electric pulse. Useful as an adjunct to wet combing.
Self-care and lifestyle
- Check all household members and treat everyone with live lice at the same time
- Do not exclude children from school unnecessarily
- Regular wet combing during outbreaks at school provides early detection
- Machine wash bedding and clothing at 60°C after treating an infestation
Prevention
Lice cannot be reliably prevented. Long hair tied back during school outbreaks may reduce contact. Regular wet combing for detection is more useful than prevention sprays.