How do you get pinworms?
Pinworm infection is spread person-to-person. The symptoms of pinworm infection are caused by the female pinworm moving and laying her eggs, and this usually occurs at night. Within a few hours of being deposited on the skin around the anus, pinworm eggs become infective (capable of infecting another person). They can survive up to two weeks on clothing, bedding, or other objects. Infection is acquired when these eggs are accidentally swallowed, usually due to inadequate hand washing by the parents and children. However, eggs on bedding or other objects that are touched while the eggs are still viable can cause infection or reinfection of people.
What do pinworms and their eggs look like (pinworm pictures)?
The pinworms are white, can be seen with the naked eye (no magnification) and are about the length of a staple (about 8-13 mm for female and 2-5mm for male worms). The eggs that are laid by the female worms are not visible as they are about 55 micrometers in diameter and are translucent (see Figure 1).
The male and female worms live for the most part within the rectum of humans but have a life cycle in humans that involves rectal/oral transmission (see Figure 2).
While an infected person is asleep, female pinworms leave the intestines through the anus and deposit eggs on the skin around the anus. This causes itching and irritation of the surrounding area; children especially will scratch the rectal/anal area, get eggs on their fingers or underneath their fingernails and transport the infective eggs to bedding, toys, other humans, or back to themselves. The eggs hatch into larval forms in the small intestines and then progress to the large intestine where they mature, mate, and progress to the rectal/anal area where females deposit about 10 to 15 thousand eggs.
Figure 1, picture of pinworm and pinworm eggs (magnified); (image courtesy of CDC.gov)
Picture of the life cycle of a pinworm
Which specialties of doctors treat pinworms?
The majority of pinworm infected patients can be treated by the patient’s primary care or pediatric physician. Rarely, an infectious disease specialist, parasitologist, OB/GYN, gastroenterologist or dermatologist is consulted.
How is the tape test used in diagnosing pinworms?
If pinworms are suspected, transparent adhesive tape or a pinworm paddle (supplied by your health care professional) are applied to the anal region. The eggs (and sometimes the parasites themselves) adhere to the sticky tape or paddle and are identified by examination under a microscope. The test is sometimes referred to as "the Tape Test."
The test should be done as soon the affected individual wakes up in the morning (because bathing or having a bowel movement may remove most eggs and parasites). The exam may require several samples for diagnosis. Samples taken from under the fingernails may also contain eggs (since scratching of the anal area is common by affected individuals).
At night, the adult worms can sometimes be seen directly in bedclothes or around the anal area: this is another good time to detect the parasites with the transparent adhesive tape method.
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Are there natural or home remedies that treat pinworms?
There are many natural and/or home remedies for pinworms although there is a lack of data to support claims. Some of the many suggested remedies include the following:
- Coconut (grated)
- Grapefruit seed extract and paste
- Grated carrots daily
- Onion juice 3 x per day for 2 days
- Pumpkin seeds
- Wormwood extract
The above are just a few of the remedies. Check with your doctors before using these remedies.
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What medicine treats pinworms?
Medication to get rid of pinworms include:
- Usually, a single tablet of mebendazole (Vermox) is used for treatment. This can sometimes be repeated a week later or, if infection persists, the medication is given again three weeks later. Some clinicians recommend a treatment protocol of a drug dose every 3 weeks, 3 times, so that the person has effective drug treatment for about 9 weeks total. Vermox has been discontinued in the US, but stocks are still available in some pharmacies.
- Another effective medication is albendazole (Albenza) but it may require other medications to reduce the inflammation of the central nervous system, a side effect of the drug. Albendazole is well tolerated with minimal side effects due to minimal systemic absorption.
- Pyrantel pamoate (Pin-Rid, Pin-X) is available over-the-counter for pinworm after confirmation of the diagnosis by a licensed healthcare practitioner. Drugs available over-the-counter vary from country to country. Pyrantel is the treatment of choice for pregnant women.
- To treat pinworms affecting urinary and genital organs, combination therapy with oral mebendazole (Vermox) and ivermectin (Stromectol) for the worms as well as topical therapy for the eggs may be required.
Most pinworm infections are treated at home with the above medications. However, reinfection is fairly common. To both reduce the chances for reinfection and to help prevent others from getting pinworms, see the prevention section.
Pinworm infections can be cured; usually by 3 doses of medication, each 3 weeks apart. Individuals are encouraged to follow-up with their doctor to be sure treatment has been effective.
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What are the consequences if pinworms aren't treated?
Untreated pinworms may cause or have a role in causing:
- Significant malabsorption of food
- Weight loss
- Genital itching
- Bedwetting (enuresis)
- Main during urination (dysuria)
- Vaginal discharge which can be associated with genital skin irritation and rash
Complications may include endometriosis, salpingitis, urethritis, urinary tract infection (UTI), vulvovagininitis, and possibly appendicitis.
Can pinworms be prevented?
Good hygiene will help reduce the spread of the parasites.
- Hand washing after handling bedding, diapers, underwear, and other items that may contain the infective pinworm eggs will also help.
- Cleaning under the fingernails and not biting the fingernails will also help reduce the chance of contacting the parasites.
- Clothes, especially underwear, should be changed and washed daily to help prevent spreading the disease.
- Treating everyone infected in a household at the same time may help prevent recurrence and spread to others.
- Because the eggs remain infective for up to three weeks in a moist environment, prevention of spread and reinfection is difficult but possible.
Reviewed on 5/27/2016
Centers for Disease Control and Prevention. "Enterobiasis (also known as Pinworm Infection)." Updated Feb 9, 2016.