The tape test detects pinworms by identifying what in the perianal area?

• A. Eggs collected on the tape sample
• B. Adult worms in stool
• C. Blood in stool
• D. Fecal bacteria

Answer: (A)

Pinworms lay their eggs around the anus, especially at night, so the most reliable way to detect infection is to collect those eggs from the perianal area. The tape test uses a piece of clear adhesive tape pressed to the perianal skin first thing in the morning, then examined under a microscope for pinworm eggs. This method targets the infectious stage of the parasite—the eggs on the skin—making it more sensitive than looking for adults or other signs. Stool tests often miss eggs because they aren’t shed consistently in feces, and blood in stool or fecal bacteria aren’t related to pinworm infection.