Parasitic Infections: Worms People Can Get
Parasitic Worms
Worms (aka helminths) are a common parasite. There are several types of worms that infect and feed on people. Some worms that people get can grow to be really big --more than 3 feet long. Others are tiny. The worst parasitic worms are usually found in warm tropical or subtropical parts of the world, but some worms are common in other places, too. Anyone can get worms.
How You Get Worms
You can get worms in different ways, depending on what type they are. Many times people get worms by accidentally swallowing them or their eggs. Some worms can go through your skin when they are young and small. Sometimes you get worms when an infected insect bites you or when you eat meat from an infected animal. Worms are often passed through the pee or poop of an infected animal or person.
Pinworms (aka Threadworms)
Pinworms, also known as threadworms, are a common type of worm in the U.S. and around the world. They usually aren't longer than 1/2 an inch. You get them when you swallow their eggs. The eggs hatch in your intestines. At night, female pinworms exit your body and lay thousands of tiny eggs around your anus. If those eggs are passed to other people, the worms spread. Pinworm infections happen most often when kids pass them to other kids. Often there are no symptoms, but they may cause:
- Itching
- Pain
- Nausea
Roundworms (Ascariasis)
Roundworms are common in warm places where there's poor sanitation. When a person swallows roundworm eggs, the worms hatch in the intestines. The young worms then go to the lungs. After a week or two, the worms go to the throat and often get swallowed again. Roundworms spread through soil mixed with infected poop or by eating raw infected meat. Symptoms include:
- Coughing
- Wheezing
- Belly pain
- Vomiting
- Diarrhea
- Fatigue
- Weight loss
Hookworms
Hookworms also are common in the tropics. When the poop of an infected person is mixed into the soil, the eggs will hatch. At a certain stage, young hookworms can go through a person's skin. This can happen if people go barefoot in places where the soil is contaminated. An itchy rash is usually the first sign of hookworms. Other symptoms include:
- Belly pain
- Diarrhea
- Weight loss
- Loss of appetite
- Fatigue
- Anemia
Strongyloidiasis
Another type of tiny roundworm (Strongyloides stercoralis) causes this disease. People mainly get them when young worms in soil go through their skin. Once in the body, the worms find their way to the small intestine and lay eggs. Those eggs hatch before they are pooped out and the worms may infect someone else. Often there aren't any symptoms, but the worms can cause:
- Belly pain
- Bloating
- Heartburn
- Diarrhea
- Constipation
- Dry cough
- Skin rashes
