Pinworm infections are very common, affecting approximately 1 billion people worldwide. People of all ages can become infected with pinworms, but the infections are found most often in children. Caregivers and family members of infected children have a higher risk of infection.
Pinworms (Enterobius vermicularis) are small, white worms about the length of a staple that live in the rectum of humans. About 20% of children will get pinworms. It is more common in school-age children than pre- schoolers. Adults are rarely affected, except for parents of infected children.
Finding the female worm or the eggs confirms the diagnosis of pinworms. To find a female worm: At night, the adult worms can sometimes be seen directly around the anal area or in pajamas. The worm (one-quarter to one-half inch long) is clearly visible to the naked eye.
If left untreated, the intense itching and scratching associated with these infections will result in secondary bacterial infections. Some of these may be difficult to treat. Untreated people can continue to infect other people.
Life cycle of a pinworm
A grown pinworm is yellowish white, slender and about one centimetre long. Around 4 weeks after ingestion, the adult female moves down the gut and exits the body via the anus to lay a batch of eggs on the surrounding skin, often at night. The worm then dies, her reproductive mission complete.
Strict hygiene measures can clear up pinworm infection without medication, and reduce the risk of reinfection. The worm has a lifespan of about six weeks, therefore the strict hygiene needs to last that long.
Typical pinworm infections don't cause serious problems. In rare circumstances, heavy infestations can cause infection of female genitals. The parasite can travel from the anal area up the vagina to the uterus, fallopian tubes and around the pelvic organs.
Call Your Doctor If:
Pinworm is seen. Skin around the anus gets red or tender. Anal itching lasts more than 1 week.
Many anti-worm preparations, for example pyrantel (e.g. brand names Anthel, Combantrin and Early Bird) and mebendazole (e.g. Combantrin-1 with Mebendazole, Vermox) can be bought over-the-counter at pharmacies. However, some are only available on prescription, such as albendazole (Zentel).
Pinworms can rarely migrate into the vagina or urinary tract causing irritation in these regions. Intense itching is again the prominent complaint. This location of infection is less common than the perianal region, and the infection usually goes away on its own.
If you are self-treating for pinworms, take the medication once only. Do not repeat the dose without talking with your doctor first. Depending on the type of worm infection you have, your doctor may direct you to take the medication only once or for several days.
The best way to diagnose this infection is to do a tape test. The best time to do this is in the morning before bathing, because pinworms lay their eggs at night. Steps for the test are: Firmly press the sticky side of a 1-inch (2.5 centimeters) strip of cellophane tape over the anal area for a few seconds.
The people most likely to be infected with pinworm are children under 18, people who take care of infected children and people who are institutionalized. In these groups, the prevalence can reach 50%.
Pinworm eggs are spread from direct transfer between hands and anus to the same person or others. Indirectly they can spread through clothing, bedding, food and other articles in the living environment. Dust may spread the eggs in heavily contaminated households and indoor environments.
Pinworm infection is very contagious. If you don't take precautions, it's easy to become reinfected. If anyone in your home has pinworms, take these steps to get rid of the pinworm eggs. Doing so will minimize your chances of reinfection.
Itching around the anus caused by a pinworm infection usually happens at night. Try wearing gloves, pyjamas, and close-fitting clothing to help prevent scratching. Bathe carefully every day. Be sure to clean the skin around the anus.
Pinworm can be treated with either prescription or over-the-counter medications. A health care provider should be consulted before treating a suspected case of pinworm infection. Treatment involves two doses of medication with the second dose being given 2 weeks after the first dose.
Chlorine dioxide gas inactivates pinworm eggs in a non-invasive and non-corrosive manner.
After a few weeks, the female pinworms move to the end of the large intestine, and they come out of the body at night to lay their eggs around the anus (where poop comes out). The amount of time that passes from when someone swallows the eggs until the worms lay new eggs is about 1 to 2 months.
The eggs pass into the digestive system, where they hatch. About 1 to 2 months later, adult female pinworms lay eggs on the skin right around the anus, which makes the area itchy. Often, this happens at night.
Why? Most people do not know they are infected or at risk, or don't have access to appropriate care. And often, health care providers are unfamiliar with these parasitic infections, and may not diagnose or treat them appropriately.
Threadworms are common but are not usually serious. Threadworms infect the gut and lay eggs around your anus, which causes itch. Treatment usually includes medication plus hygiene measures.