Head lice ( Pediculus humanus capitis)

Overview

Head lice are parasitic insects that are found on the scalp. Having head lice is very common affecting school children in great numbers every year. Unlike body lice a completely different creature head lice do not transmit diseases. They can however seriously disrupt family life because finding and eliminating the lice can be frustrating and time consuming.

Symptoms

The first tell-tale sign of head lice is an itchy scalp. You may notice your child scratching his or her head frequently. Other signs of head lice are:

  • Tickling feeling of something moving in the hair.
  • Irritability.
  • Sores on the head caused by scratching.

Often however you won't even know your child is infected until he or she is sent home from daycare or school after a routine inspection by a public health nurse.

Causes

You can get head lice by coming into contact with either live lice or their eggs.

  • By contact with an already infested person. Contact is common during play at school and at home (slumber parties sports activities at camp on a playground).
  • By wearing infested clothing such as hats scarves coats sports uniforms or hair ribbons.
  • By using infested combs brushes or towels.
  • By lying on a bed couch pillow or carpet that has recently been in contact with an infested person.

Treatment

The following people should be seen by a doctor:

  • children under the age of 2
  • pregnant women
  • breastfeeding mothers
  • anyone with a skin irritation
  • anyone with a seizure disorder

Others may want to contact their doctor or the local public health office for advice about treatment options. There are a number of effective products that are readily available at your neighbourhood drug store. You won't need a prescription and you can ask your pharmacist for help. Toronto's Hospital for Sick Children recommends this natural treatment:

  • douse hair with 50/50 solution of mineral oil and vinegar
  • cover hair with a shower cap for an hour
  • wash with regular shampoo

If you purchase a commercial product follow the directions on the package. This usually involves shampooing and rinsing the hair with the treatment and then combing out the nits. You may have to repeat the treatment the following week if there are signs of live lice or new nits. Regularly check your child's head for 3-4 weeks to make sure the problem hasn't returned. Check yourself as well. If anyone in your home has head lice everyone will have to be inspected and treated if necessary.

What to look for:

  • Nit: Nits are head lice eggs. They are hard to see and are often confused for dandruff or hair spray droplets. Nits are found firmly attached to the hair shaft. They are oval and usually yellow to white. Nits take about 1 week to hatch.

  • Nymph: The nit hatches into a baby louse called a nymph. It looks like an adult head louse but is smaller. Nymphs mature into adults about 7 days after hatching. To live the nymph must feed on blood.

  • Adult: The adult louse is about the size of a sesame seed has six legs and is tan to greyish-white. In persons with dark hair the adult louse will look darker. Females lay nits; they are usually larger than males. Adult lice can live up to 30 days on a person's head. To live adult lice need to feed on blood. If the louse falls off a person it dies within 2 days.

Prevention

  • Do not share hats hair brushes combs towels or headphones
  • Make sure you alert your child's school daycare or recreational group if they have lice.
  • In the future consider a regular routine of checking your children for nits