By Martha A. Simpson, D.O., M.B.A.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

MEDICATION, HAND-CLEANLINESS KEYS TO TREATING PINWORMS

Question: My cat was recently treated for worms. Then my 6 year-old son got pinworms, which required treatment. He must have gotten them from the cat since we are very clean people. Should I get rid of my cat?

Answer: Pinworms or thread worms -- known to the medical world as “Enterobius vermicularis” -- are the most common type of human worm infestation in the United States. This infestation is most often seen in children between the ages of 5 and 14. These worms belong to a class of critters known as helminthes, most of which are parasitic. The specific pinworm variety, however, only lives in humans, so they did NOT come from the cat. Your cat must have had a different type of parasitic worm.

Pinworms eggs are infective almost as soon as they are laid. The life cycle of the pinworm starts when a human swallows pinworm eggs. The eggs hatch just below the stomach in the duodenum. The larva then move on to the small intestine, where they mature into adult pinworms. Their next stop is the large intestine, or bowel. While living in this habitat, the female moves at night to the rectal area and lays her eggs. A single female can lay up to 15,000 eggs each night. These are invisible to the naked eye and become infective in about 6 hours.

The eggs contaminate hands, sheets, bed clothing, rugs, and counter tops, and use the dust in your house to travel widely. Humans pick up these infective eggs, then contaminate food they pick up or bite their own fingernails, and the pinworm cycle continues. Eggs can survive on contaminated surfaces for up to two weeks. They are highly contagious.

The primary symptom is itching in the rectal area --sometimes quite severe. The female worms can be easily seen with un-aided vision in the rectal area. At night, children may become restless, cry and complain of itching in the anal area.

The treatment for pinworms is a chewable prescription medication that sometimes is repeated in two weeks. There are also some over-the-counter medications, but you should check with your doctor before treating your children with these products. Many doctors recommend treating other members of the household even if they have no symptoms.

Once the infestation has begun in your home, it is important to help break the cycle by destroying as many eggs as possible. Here are some tips to help do that: Change bed linens and underwear every morning. Take sheets and clothing straight to the washing machine for a hot water wash, being careful not to shake them. Open curtains and let the sun shine in to help to kill the sun-sensitive eggs. Avoid putting your hands into your mouth, especially nail biting.

Hand cleanliness is mandatory. Wash your hands thoroughly before meals and after using the toilet. You should keep your nails short, and clean them regularly with a nail brush. This will eliminate a place for the eggs to hide. Wet wiping food preparation surfaces prior to preparing meals can also help.

Once the pinworm infestation has been controlled, you should turn your focus to prevention. Continuing to practice good hand cleanliness and the other measures I’ve mentioned will make another bout with pinworms less likely. But, you’ll be relieved to know, the cat can stay.

Family Medicine® is a weekly column. To submit questions, write to Martha A. Simpson, D.O., M.B.A., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701, or via e-mail to readerquestions@familymedicinenews.org. Medical information in this column is provided as an educational service only. It does not replace the judgment of your personal physician, who should be relied on to diagnose and recommend treatment for any medical conditions. Past columns are available online at www.familymedicinenews.org.