Threadworms

What are threadworms?

Threadworms (also known as pinworms) are common, highly contagious parasites that live in the human gut. They look like small, white pieces of thread and spend their lifecycle inside your body. While they are physically harmless in most cases, they shift how you feel at night, as the female worms crawl out of the rectum to lay thousands of microscopic eggs on the surrounding skin.

Threadworms strike at any age, but they are most common in children. Because the eggs spread so easily, if one person in a household has them, it is very likely the rest of the family does too.

Symptoms of threadworms

Symptoms often go unnoticed during the day, but they become impossible to ignore at night. The most common sign is intense itching around the bottom or vagina, which usually gets worse when you are trying to sleep. You may also notice small, white worms in your stool or around your child's bottom at night.

In some cases, the infection can cause more than just an itch. If the scratching becomes severe, the skin can break and become infected. If you notice severe pain, pus, or swelling around the area, or if a child is unable to sleep for several nights and is losing weight, you should seek medical help to ensure there isn't a secondary infection.

What triggers threadworms?

The "trigger" for a threadworm infection is always the accidental swallowing of their microscopic eggs. Once inside, the eggs hatch in the gut. The cycle continues because the eggs are incredibly sticky and can survive for up to three weeks outside the body.

Common ways threadworms spread include touching surfaces like door handles or toys that have eggs on them, sharing towels or bedding with an infected person and most commonly scratching the itchy area at night and then touching your mouth or food with unwashed hands.

Managing threadworms and using treatments

A threadworm infection won't just disappear on its own because the eggs can survive for weeks, leading to constant re-infection. The secret to winning the fight is to treat the whole family at the same time, even if they don't have symptoms and to follow a strict 6-week cleaning routine to kill any remaining eggs.

Most plans to fight threadworms rely on two main steps:

First, you use medication (like Mebendazole). This comes as a single tablet or liquid dose that dives into the gut to paralyze and kill the adult worms. It is highly effective at clearing the current infection, but it does not kill the eggs that have already been laid.

Second, you must follow strict hygiene measures. Because the eggs can still hatch after you take the medicine, you must wash all bedding at a high temperature, keep fingernails short to prevent eggs from hiding underneath, and scrub your hands every morning to wash away eggs laid during the night.