Pinworm Infection

Warning: the following blog post is not for the squeamish!

San Francisco Primary Care PediatricianWhat did one astronaut pinworm say to the other…? Let’s explore Uranus!

What are pinworms?

Pinworms are the most common parasitic infection in the United States with a general incidence rate of about 11% among people of all ages. Pinworms are small, white, thread-like organisms that infect the large intestine and anal area.

How is pinworm infection spread?

Most cases of pinworm occur in school-aged children and caregiver/family members of infected children. When an individual is infected, the female pinworm exits the rectum at night (during sleep) to lay eggs around the anus and the perineum. Infection is spread from person to person when an individual inadvertently ingests the pinworm eggs left by an infected person on toys (typically) and surfaces. This typically happens when children with pinworms scratch or wipe their bottoms and then leave eggs on the things they touch. Outbreaks of pinworm often occur in daycare and school settings. It is also common that children re-infect themselves, especially among those who suck their thumbs or fingers.

What are the signs and symptoms of pinworm?

Most commonly pinworm infection causes severe itching and some irritation of the anus and/or the vagina in girls. Other symptoms include: difficultly sleeping secondary to itch, rash or skin irritation around the anus/vagina, and occasionally abdominal discomfort and nausea.

How is pinworm diagnosed?

Diagnosis if often based off signs and symptoms alone, especially in children who are having symptoms at night. Pinworms may be seen in and around the anus shortly after a child goes to bed — take a flashlight and inspect after they’ve fallen asleep. Worms may also be visible in the stool. Eggs from pinworms are transparent and cannot be seen by the naked eye.

How is pinworm treated?

Pyrantel pamoate is an over the counter treatment for individuals with pinworm infection. It is taken in two doses, two weeks apart. It is recommended that the whole family take treatment to minimize the risk of infection spreading or reinfection. Since pinworm eggs can live outside of the body on surfaces and inanimate objects for up to 3 weeks, it’s important to carefully wash underwear, linens, towels, and commonly used toys/objects in hot water. Laundered items should be dried in high heat to kill off any residual eggs. Children with infection should have their nails cut short and have assistance with thorough washing of the anal area each morning to reduce the number of eggs that were potentially laid overnight. Lastly, frequent hand washing is best way to prevent the spread of pinworm!