What are pinworms (oxyures), how do you become infected with pinworms and what symptoms does an infection with pinworms cause? An infection with pinworms is the most common worm infection in the Netherlands and it is especially annoying because of the anal itching that accompanies such an infection. An infection with pinworms or getting worms is generally considered a typical childhood ailment, but adults can also suffer from it. Pinworms are treated with worm-killing medications. Good personal hygiene is important to prevent an infection with the pinworm.
- An infection with pinworms
- Risk groups
- Pinworm symptoms
- Complications
- Pinworm infestation and causes
- Pinworm eggs
- Self-contamination and contamination of others
- Life cycle of the pinworm
- Incubation period
- Pinworm risk factors
- Examination and diagnosis
- Treatment of pinworms
- Medication for pinworms
- Hygiene measures
- Other measures
- Prevention
- Wash hands
- Clipping nails and changing bed linen
- Wash in the morning
- Do not scratch
- Disease course and prognosis
Adult pinworms / Source: Public domain, Wikimedia Commons (PD)
An infection with pinworms
An infection with pinworms is the most common worm infection in the Netherlands and one of the most common worldwide. The official name of the pinworms is Enterobius vermicularis or oxyuris. The pinworm belongs to the roundworms, a large group of very common worms. Pinworms are thin and white, and range in size from about 5 to 13 millimeters. Colloquially they are referred to as ‘worms’. You see them crawling around in the feces after infection and the anal itching can be maddening. While the infected person sleeps, female pinworms lay thousands of microscopic eggs in the folds of the skin around the anus. This can cause severe itching. Treatment consists of a vermifuge and thorough washing of bedding and underwear. For the best results, the entire family must be treated.
Risk groups
The people who are infected most often are children under the age of 18, people who care for infected children and people admitted to a healthcare institution.
Stomach pain due to pinworms / Source: Andrey Popov/Shutterstock.com
Pinworm symptoms
Characteristic of an infection with pinworms is that itching complaints occur at night in the anus, in the buttocks and sometimes in the labia. In addition, abdominal pain and nausea may occur. A child can sometimes have difficulty sleeping due to itching and can therefore be tired and irritable during the day. Scratching can lead to inflammation, broken skin and a burning anus. You can sometimes see moving worms crawling around in feces.
Complications
Typical pinworm infections do not cause serious problems. In rare cases, heavy infestations can cause infection of the female genital tract. The parasite can travel from the anal area to the vagina and then to the uterus, fallopian tubes and around the pelvic organs. This can cause problems such as inflammation of the vagina (vaginitis) and inflammation of the lining of the uterus (endometritis).
Other (rare) complications of an infection with the pinworm are:
- urinary tract infection
- weight loss
- infection of part of the abdomen (peritoneal cavity)
Pinworm infestation and causes
Pinworm eggs
Pinworms are a human parasite, just like the head louse and the scabies mite. This means that contamination only occurs from person to person, usually by ingesting eggs on the fingers of an infected person (self-contamination). Pinworms are found in the lower part of the colon and cecum, but at night the female worms crawl to the anal area and lay their eggs on the skin around the anus. This can lead to intense itching and scratching often spreads the eggs further. The eggs can get under the fingernails and if the child brings his fingers to his mouth, he can ingest these eggs. These eggs can also be transferred to other children, family members, and stick to objects in the home or school, such as toys, furniture or clothing. The eggs can end up on fingers or in food to infect someone else. The swallowed eggs hatch in the duodenum and the larvae descend further, completing the circle. Moreover, the eggs can remain alive for a long time outside the body.
Self-contamination and contamination of others
The male is about half a millimeter in size, the female up to 1.5 centimeters long. After fertilization, the female migrates to the anus. There it lays up to 10,000 or more eggs at night in the skin folds immediately around the anus. This creates an itching sensation, which triggers a scratching reflex. As a result, eggs quickly end up on the hands and under the fingernails. If the infected fingers are put in the mouth, self-contamination is possible.
The eggs can also be transferred to objects during food preparation or through hand contact. The eggs remain infectious for up to three weeks in a moist environment. This makes re-contamination of the remaining eggs possible, even after successful treatment.
Pinworms are mainly transmitted by hand contact. They end up in the mouth through the hands and are swallowed. An important risk factor is poor hygiene and careless hand washing. The parasite can also be transmitted during sexual intercourse. Anal-oral practices in particular make infection possible.
Life cycle of a pinworm / Source: Centers for Disease Control & Prevention (CDC, http:www.dpd.cdc.govdpdx), Wikimedia Commons (Public domain)
Life cycle of the pinworm
The life cycle of this nuisance begins with eating the eggs of the pinworm. These empty into the duodenum. That is the first part of the small intestine, where food is mixed with all kinds of juices such as gastric juices, bile, pancreatic juices and intestinal juices. The larvae grow quickly. They reach a size of 140 to 150 micrometers. They then migrate through the small intestine to the large intestine. This is the place in the intestine where food remains are absorbed into the body that the small intestine has not been able to process. During this migration they molt twice and mature.
The male and female pinworms mate in the ileum or ileum. That is the last part of the small intestine. After that, the male pinworms usually die; they have completed their task. They are then expelled with the feces. The pregnant female pinworms settle in the ileum, the cecum (beginning of the large intestine), the appendix and the right-sided part or ascending part of the large intestine where they attach to the mucous membrane and swallow the contents of the large intestine. Almost the entire body of a pregnant pinworm becomes filled with eggs. It is estimated that there are many thousands of eggs, somewhere between 10,000 and 16,000. Egg laying begins approximately five weeks after the pinworm eggs are first ingested by the human host. The females migrate through the colon to the rectum at a rate of 12 to 14 centimeters per hour and emerge at the anus. Oxygen is needed for the eggs to mature. They come out at night and lay eggs around the anus. There the eggs cause itching in the anus and in the buttocks. After laying the eggs, the female becomes opaque and soon dies.
Small intestine, cecum with vermiform appendage and large intestine / Source: Henry Vandyke Carter, Wikimedia Commons (Public domain)
Incubation period
The incubation period or incubation period is the time that elapses between infection and the first clinical symptoms. Once someone has swallowed pinworm eggs, the incubation period is 1 to 2 months. Once mature, the adult female worm migrates to the large intestine and lays eggs around the anus at night, when many of their hosts (especially children) are asleep. People infected with pinworms can transmit the parasite to others as long as there is a female pinworm laying eggs on the perianal skin. A person can also reinfect themselves or become reinfected with eggs from another person.
Pinworm risk factors
Risk factors for an infection with pinworms are:
- Age. Children in particular (a toddler, toddler or preschooler) often contract them, for example in daycare centers or kindergartens. The microscopic eggs can easily be spread to family members, parents, caregivers or other children at school or daycare.
- Living in small, communal spaces. People who live in institutions are at greater risk of infection with pinworms.
Examination and diagnosis
The diagnosis is often made on the basis of the patient’s complaints and the observations of the parent(s) and/or caregiver(s). Pinworms can be found in the feces as small, moving white-yellow worms. In addition, itching near the anus during the night is a characteristic symptom.
Rub the buttocks with Vaseline / Source: Kiyok, Wikimedia Commons (CC BY-SA-3.0)
Treatment of pinworms
Medication for pinworms
A wormicide can rid you or your child of pinworms. Mebendazole is a drug that is available over the counter from pharmacies. Read the package leaflet before use. It is wise to treat all people in the household to prevent reinfection.
Hygiene measures
In addition to medication, good hygiene is important:
- Put on clean underwear every day and every night.
- Wash underwear and bedding at at least 60 degrees.
- Cut children’s nails short.
- Regularly thoroughly clean hands and nails with disinfectant soap.
- Wash your hands and nails thoroughly with disinfectant soap both before and after sleeping
- Regularly clean toys, doorknobs, the kitchen and the toilet.
Other measures
You can also put tight underpants on your child during the day and at night, so that he or she is less likely to scratch. Apply an anhydrous ointment to the buttocks, such as Vaseline. This helps prevent itching and pain.
Wash hands after pooping / Source: Pezibear, Pixabay
Prevention
Wash hands
Washing hands with soap and warm water after using the toilet, changing diapers and before eating food is the most successful way to prevent pinworm infection. To stop the spread and possible reinfection, people who are infected should rinse their anus in the shower every morning, which removes much of the eggs on the skin. Infected people are not allowed to share the bath with others during the period that they are infected.
Clipping nails and changing bed linen
It is useful to regularly cut fingernails and avoid nail biting. Changing underwear and bedding regularly is a good way to prevent possible egg transmission and reinfection. Do not shake out the bedding, but carefully place it in a washing machine and then wash it at at least 60 degrees, followed by a hot dryer to kill any eggs.
Wash in the morning
Because pinworms lay their eggs at night, washing the anal area in the morning can help remove some of these eggs from your body. Showering can help prevent possible reinfection in bath water.
Do not scratch
Avoid scratching the anal area. Trim your child’s fingernails so there is less room for eggs to collect. Suggest that your child not bite his or her nails.
Disease course and prognosis
An infestation with pinworms is usually harmless. Complications are rare. It is especially common in children to re-infect themselves at night. By scratching around the anus and then sucking on fingers/thumbs, the eggs come directly from the anus to the mouth.
The drug treatment is very well tolerated and there are few side effects. Complications are also rare. Sometimes the worm eggs end up in the vagina where they develop further. This causes an inflammatory response, which may be accompanied by pain and possibly discharge. If the infection is severe, intestinal function may be limited and inflammation may occur.
read more
- Pinworms: small white worms around the vent or anus
- Worms in humans: causes worms in intestines and feces
- Small white worms in feces: cause and treatment
- Anal itching (itchy anus): causes of itching of the anus
- Itchy anus after stool, with blood or worms
