Helminthiasis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Helminthiasis?
An infectious disease doctor, a doctor who treats infections caused by germs and parasites, often treats helminthiasis. Many people first see a primary care doctor, who can arrange a stool test. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is helminthiasis?
Helminthiasis is an infection with helminths, which are parasitic worms. A parasite is a living thing that lives on or in another living thing and gets its food from it. Helminths are large, many-celled organisms. Adult worms can generally be seen without a microscope. In their adult form, they cannot multiply in humans.
There are three main groups of helminths that infect people. Flatworms include flukes and tapeworms. Thorny-headed worms are the second group. Roundworms are the third. Their adult forms can live in the gut, blood, lymph system, or tissue under the skin.
The details below mostly describe soil-transmitted worms. These are roundworm (Ascaris), whipworm, and hookworm. They live in the human intestine and are among the most common human parasites in the world.
Symptoms
People with only a few worms usually have no symptoms. Heavier infections can cause a range of health problems, including:
- Belly pain.
- Diarrhea.
- Loss of blood, protein, and other nutrients.
- Rectal prolapse, which is when the rectum sags and comes out of the anus.
- Slow physical and mental growth in infants and children.
Heavy infections can also cause a general feeling of weakness. Hookworms cause long-term blood loss in the gut, which can lead to anemia, a low red blood cell count. Anemia is more likely in teen girls and women of childbearing age.
Very heavy infections can block the intestine. A blockage like this needs to be treated with surgery.
Causes and who gets it
Soil-transmitted worms spread through soil or water that is contaminated with human feces (stool) containing the worm eggs or larvae. Larvae are immature worms. Infections occur in warm, moist areas where sanitation and hygiene are poor. They may occur in temperate climates during warmer months.
People can swallow roundworm or whipworm eggs in several ways:
- From vegetables or fruits that are not carefully washed, peeled, or cooked.
- From contaminated drinking water.
- From hands or fingers that touch the mouth without being washed first.
You cannot get hookworm from hookworm eggs. The eggs hatch in soil, and the larvae can enter the skin. Hookworm spreads mainly by walking barefoot on contaminated soil. One kind of hookworm can also spread through eating the larvae.
The World Health Organization lists these groups as high risk: preschool and school-age children, women of childbearing age, and adults in jobs with a high risk of heavy infection.
How doctors diagnose it
Your health care provider can take a stool sample and look at it under a microscope. This test looks for a soil-transmitted worm infection.
A related worm called Strongyloides needs different methods to find it. For this reason, it is often missed.
Treatment
Only prescription drugs can treat soil-transmitted worm infections. The medicines, such as albendazole and mebendazole, are called anthelmintic medicines. Treatment lasts between one and three days and is highly effective, whatever the type of worm.
Strongyloides does not respond to albendazole or mebendazole. Ivermectin is available to control it. In people with weak immune systems, Strongyloides can multiply out of control and can be fatal.
In some tropical regions, people at higher risk are treated without a stool test first. This is called preventive treatment.
When to see a doctor
See your health care provider if you think you have a soil-transmitted worm infection. Strongyloides can be fatal in people with a weak immune system.
Call 911 or go to the emergency room if you have severe belly pain or pressure, or severe or persistent vomiting or diarrhea. Very heavy infections can block the intestine.
You can lower your risk in these ways:
- Wash your hands before handling food.
- Wash, peel, and cook raw fruits and vegetables.
- Avoid soil and drinking water contaminated with human feces.
- Wear shoes when walking on soil that may be contaminated, to prevent hookworm.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Either can order tests, explain the results, and follow up on your recovery. They can also refer you to an infectious disease doctor when needed.
Common questions
Do worm infections always cause symptoms?
No. People with only a few worms usually have no symptoms. Heavier infections can cause belly pain, diarrhea, and loss of nutrients.
How do doctors test for worm infections?
Doctors test for worm infections by looking at a stool sample under a microscope. Your provider can take the sample for soil-transmitted worms.
Can I catch soil-transmitted worms from another person?
Not directly. Eggs passed in stool need about 3 weeks to mature in soil before they can infect someone, so there is no direct person-to-person spread.
How long does treatment for soil-transmitted worms last?
Treatment lasts between one and three days. It is highly effective, whatever the type of worm.
How can I lower my risk of a worm infection?
You can lower your risk by washing your hands before handling food and by washing, peeling, or cooking raw fruits and vegetables. Avoid contaminated soil and water, and wear shoes on soil that may be contaminated.
Sources
- CDC - About Parasites
- CDC - About Soil-transmitted Helminths
- World Health Organization - Soil-transmitted helminth infections
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
