FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

SHARING COMBS, HATS OR PILLOWS CAN SPREAD HEAD LICE

Question: My son's school called and told me that my child had head lice. Before this episode, I thought that only people with poor hygiene got lice. Obviously, I was misinformed. The school said I needed to pick him up, and then I'd have to treat him with a special medication in order to get rid of the lice before he could come back to school. How did he get lice, and what is the best way to keep him from getting them again?

Answer: Lice are a type of wingless insect that live on humans and most other animals. Fortunately, there are only three varieties of lice that infest humans, and these don't infest our livestock or pets: Pediculus humanus corporis (body lice), Pediculus humanus capitis (head lice), and Phthirus pubis (pubic lice). As you've noticed, these lice are named for the areas of the body where they are usually found. Therefore, your son has Pediculus humanus capitis.

All of these lice survive by using humans as their food source. They bite the skin, consume blood, and lay their eggs on the unlucky individual. Their entire life cycle requires humans.

The scalp of an individual with head lice has sores where the insects have bitten. While these sores are somewhat itchy, the victim may not complain much about them. The most obvious sign of head lice is the presence of eggs. These eggs, called nits, are small gray-white colored oval-shaped structures. Each nit is cemented to the shaft of a hair strand at scalp level. As the hair grows, it carries the nit further from the surface of the scalp.

Head lice can live for up to two days off of a human host. It is possible to acquire your own personal head louse by close personal contact with someone who has them or by using a pillow, hat or comb of the infested person. The transferred louse then establishes a new home on your head. Children are often infested in this way. The nit is spread in the same way as the adult louse, but it is even sturdier than the parent. A nit can remain capable of producing infestation for up to 30 days.

Several medications are effective at killing adult head lice as well as nits. These are usually in the form of shampoos and may contain 1 percent permethrin, brand name Nix; 1 percent pyrethrins, brand name Rid; or 1 percent lindane, brand name Kwell. All these medicated shampoos work quite well. Each one should be applied for at least five minutes and then washed off the hair and scalp. This kills adult lice and nits, but it doesn't remove nits from the hair. Repeated combing with a very fine toothed comb is necessary to do this.

To prevent reinfestation, all of the clothing, bedding, furniture, carpets and other items that have come in contact with the infested person's head in the last 30 days the period the nit can survive off of a human host should be treated. Clothing can be laundered, but an insecticide spray is usually necessary to treat the furniture and carpets.

Lice are a common complication of living in communal groups. Keeping your child inside a plastic bubble will isolate him from another episode of lice. I think there is a better solution, however. Encourage your son to wear only his hat and to let no one else wear his. He should also only use his own comb or brush. This, plus the preventive measures practiced in schools, is usually sufficient to prevent repeated episodes.

Schools actively screen children for head lice to help prevent an epidemic of this annoying infestation. The school nurse or classroom teacher looks through the children's hair for the telltale nit. It is normal to be disgruntled with the teacher for bringing you the news that your child has lice, but you shouldn't be. She is doing more than her part to keep the children in her class healthy. Give her a smile and a "thank you" when your child goes back to class without lice.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.