Pinworms, also known as threadworms, are a common parasitic roundworm infection in humans caused by the species Enterobius vermicularis. They primarily affect children but can infect anyone. Pinworm infections occur when pinworm eggs are ingested, usually through contaminated hands, food, or surfaces. The female pinworms lay eggs around the anus, causing intense itching especially at night. The eggs can spread easily to others or cause reinfection if transferred to the mouth from fingers or objects. The typical symptoms of a pinworm infection include anal itching, disturbed sleep, and sometimes abdominal discomfort. Many infected individuals may show no symptoms at all. The infection is generally mild and easily treated with antiparasitic medications such as mebendazole, albendazole, or pyrantel pamoate. Treatment usually involves two doses two weeks apart, and all household members should be treated to prevent reinfection. Hygiene measures include regular hand washing, keeping fingernails short, washing bedding and clothes in hot water, and bathing frequently. Pinworm eggs can survive on surfaces for up to two weeks, making it easy to spread in close living quarters like schools, homes, and care facilities. Pets are not carriers of pinworms. The entire pinworm life cycle—from egg ingestion to egg laying by adult females—takes about 4 to 8 weeks. In summary, pinworms are a common, contagious, and treatable intestinal worm infection in humans, characterized mainly by anal itching caused by female worms laying eggs around the anus at night.
