I have recently answered a few questions about pinworm infections, so I thought this would make a good topic for our Health Tip this week.

What is a pinworm infection?
The pinworm is a parasitic worm which is in the class of worms called roundworms.  It is a tiny white worm, which is thin and shorter than ½ inch long.  It has the largest geographic range of any parasitic worm, and is the most prevalent human parasitic worm in the United States. It is quite common, with more than 30% of children worldwide infected.  It is most common in children, but anyone can get it.  Adults frequently get it from their kids.

What are the symptoms of pinworm infection?
The usual symptom of infection is itching in the anal area.  This itching is usually most severe at night, so kids who have pinworm infection are also restless at night and move around a lot in the bed.

You may actually be able to see the tiny worms on your child’s bottom at night.  Or you may see them in your child’s stool.  Pinworm eggs are so small that they are only seen under the microscope.

How is a pinworm infection spread?
Pinworms are easily spread from child to child.  When a child has an itchy bottom, they will scratch it.  This allows the tiny eggs to get on the child’s hands and especially under their fingernails.  They can then stay on the skin for several hours, and are easily spread to a playmate through a toy or direct contact.  Children often put their hands or toys into their mouths.  That microscopic egg will then enter the intestinal tract and the infection has begun.

Children who are infected will have pinworms or more commonly their eggs, on their clothing or on their bed sheets.  The eggs can then be transferred all around the house and to other family members.  Sometimes this happens simply from Mom or Dad shaking the covers while helping to make the bed.

Pets do not spread pinworms.  This particular worm is only carried by humans.

How do we diagnose pinworm infection?
A tape test is the best test to diagnose pinworms.  Pinworms usually crawl out of the anus while a child is asleep to lay eggs.  The tape test takes advantage of this fact.  To do a tape test, when your child first wakes up, before they get out of bed, pat a small piece of clear tape on the skin around the anus.  Then fold the sticky side of the tape together.  Do this for 3 days in a row, then take the tape to your child’s doctor.  The tape is examined under the microscope for pinworms or their eggs.

How is pinworm infection treated?
Most pinworm infections are easily treated.  The treatment of choice is a prescription medicine called mebendazole.  It is a single chewable tablet, which is taken once, then again about 2-3 weeks later if the infection is not cured.  There is another medication called pyrantel, which is available over the counter.  This medication is not quite as reliably effective, so it is generally recommended to repeat the dose in 2-3 weeks, whether you feel the first dose was effective or not.

In addition to the medication, you must take other steps to rid your home of pinworms to minimize the chance of reinfection or spread to other family members.  These steps should be taken at the same time as the medication is given, and repeated until the 2- 3 week repeat dose.  These steps include:

• Wash all sheets, blankets, towels, and clothing in the house in hot water.
• Carefully clean under every family members’ fingernails and cut them short.
• Scrub toys, countertops, floors, and any surface that the infected child has touched.
• Vacuum all carpets and rugs.

Here is a link to more information about pinworms from the CDC.  https://www.cdc.gov/parasites/pinworm/index.html

If you have any more questions just Ask Hanna, our health advisors are here to help.

Dr. Anita Bennett MD – Health Tip Content Editor
Image: ©Shutterstock / Elena Abrazhevich