The intestines are a natural breeding ground for some parasites due to the ready availability of food and protection from the immune system. One class of intestinal parasites is called roundworms, and they spread from patient to patient via the fecal-oral route (the inadvertent ingestion of the organisms after they are passed from the anus).
Features
According to the Centers for Disease Control, a pinworm is a thin and white roundworm (also known as a nematode) that is approximately the size of a staple. The scientific name of pinworms is Enterobius vermicularis. These parasites live in the gastrointestinal tract and, according to the Mayo Clinic, are the most common intestinal parasite in the United States.
Transmission
The National Institute of Allergy and Infectious Diseases (NIAID) explains that people contract pinworm when they swallow the eggs. The eggs can spread to a person's hands if they scratch the area around the anus (which is where the eggs are laid) and then touch other surfaces. Eggs can also get onto linens and towels and spread via these materials. Eggs can survive for between two to three weeks on cloth.
Symptoms
The Mayo Clinic explains that many people who have pinworms do not have any symptoms, as the worms are fairly small and do not cause major gastrointestinal problems. Because female pinworms leave the intestines at night to lay their eggs, their movements can sometimes cause itching around the anus (and vagina in women). This itching can be intense and interfere with sleeping.
Diagnosis
The NIAID explains that the most common method of diagnosing a pinworm infection is to look for the eggs. One way of doing this involves placing a piece of cellophane tape on and around the anal region. The eggs will stick to the tape, which can then be removed and placed under a microscope. From there a doctor can detect the eggs to make the diagnosis.
Treatment
The Mayo Clinic notes that people who have a mild pinworm infection or are asymptomatic may not ever require treatment. In more serious cases, however, the patient can be treated with antiparasitic drugs. Commonly prescribed anti-parasite drugs include albendazole, mebendazole and pyrantel. In some cases the patient's entire household may be treated to help avoid reinfestation.
