Misconceptions about headlice: what does the research really show?

A review article in this week’s BMJ dispels some of the myths about treating head lice, using the most up-to-date medical research. For example, it shows that:

Head lice are harmless
Head lice on clothing or furniture cannot infect a person
Cutting hair, or tying it back, is not helpful
Banning children with nits from school is ineffective

Head lice are parasites that usually infest the scalps of school age children. Lice attach their eggs to hair shafts near the scalp and lay five to six eggs a day.

According to the evidence, chemical treatments such as Malathion, Lindane, Permethrin and Pyrethrins are likely to work. Treatments that need further study include herbal preparations and aromatherapy, and mechanical removal of lice by combing.

There is no evidence to support the cleaning of sheets and clothing, or the treating of furniture with insecticide sprays, says author, Beth Nash. Lice seen on chairs, pillows, and hats are dead, sick, or elderly or are cast skins of lice and cannot infect a person.

Banning children with nits from school does not make sense, she adds. About half of children sent home for head lice don’t have them and many public health experts believe that “no-nits” polices in schools should be abandoned.

Many people believe that cutting hair, or tying it back, will help, but this is not the case, and may even increase the incidence of infestation by making it easier for lice to move off and on to the scalp, she explains. Head lice are probably more common in girls because girls are more likely to have close contacts during play, not because they have longer hair.

Finally, head lice are harmless. If detached from their host they are vulnerable and effectively dead.

The information in this article is an extract from BestTreatments* – a web site for patients and doctors that tells you which treatments really work.