Threadworm is…
…an infection that occurs when threadworm parasites infest human intestines after threadworm eggs—which are not visible to the naked eye—are swallowed. It is also known as pinworm.
Symptoms
The main symptom of threadworm is itching in the anal area, which varies from mild to acute pain and occurs mainly at night. People with threadworm infection often do not have any symptoms. Sometimes threadworms—which have a white, thread-like appearance—are seen on a patient’s skin or in their stools. Other general symptoms may include insomnia and restlessness and some children may have a loss of appetite, lose weight and be irritable.
Read more about Enterobius vermicularis (threadworm) in the factsheet for the general public.