Lice

Symptoms

An itchy scalp is the main symptom of lice. The itchiness is caused by an allergic reaction to the saliva that the insect injects in the scalp to feed on blood. However, some people with lice do not have itching. An inspection of the head is the best way to find lice or nits. As they’re generally less than 10 to 20 live lice on the head, it is extremely important to conduct a thorough inspection. 

Inspecting the Head for Lice

Good lighting is important in order to see lice moving because they run from light. A fine comb and, if possible, a magnifying glass, are perfect tools. Wet the hair to facilitate parting it with the fine comb.

To inspect the head:

  • Part the hair into thin sections about the width of the nit comb. If the hair is very long, split in 2 cm locks.
  • Comb the hair from the roots close to the scalp and through to the tips, one section at a time.
  • Inspect the hair by sections from one side of the scalp to the other, and from the hairline to the back of the neck, paying particular attention to the back of the ears and to the neck.
  • If you find lice or nits on the comb, end the inspection and apply anti-louse treatment as soon as possible. See the Treatments section for products to use. 

Repeat inspection of the head as follows:

  • At least once a week after washing the hair, especially during back-to-school period
  • Daily if people in your surroundings have lice
  • As soon as the scalp feels itchy

Do not forget to wash your hands after each inspection.

Last update: July 12, 2017 1:15 PM

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