Hookworm in Humans: Symptoms & Treatment

Hookworm in humans is an intestinal worm infection caught when tiny larvae in contaminated soil burrow through bare skin, usually the feet, and travel to the small intestine, where the adult worms attach and feed on blood. Many people have few or no symptoms, but heavier infections can cause belly pain, diarrhea, tiredness and iron-deficiency anemia, and a clinician may prescribe an anti-worm medicine such as mebendazole.

Two human hookworm species cause most infections: Necator americanus and Ancylostoma duodenale. This page covers that human intestinal infection. The itchy, wandering skin tracks people sometimes get from dog or cat hookworms are a different condition, covered further down.

How do humans get hookworm?

The CDC explains that an infected person passes hookworm eggs in their stool. Where human waste reaches the soil, through outdoor defecation, poor sanitation or the use of human waste as fertilizer, the eggs hatch and release larvae. The larvae then develop into a form that can pierce human skin.

You get hookworm by:

• Walking barefoot, or letting bare skin touch soil, in places where human waste contaminates the ground
• Less often, by swallowing larvae, which is another way one species (Ancylostoma duodenale) can infect people

You cannot catch hookworm from the eggs themselves; they must first hatch and develop in soil. After entering the skin, the larvae travel through the bloodstream to the lungs, are coughed up and swallowed, and settle in the small intestine. MedlinePlus notes the adult worms can live there for a year or more.

Hookworm symptoms in humans

According to the CDC, some people with hookworm have few or no symptoms. When symptoms happen, they often come in stages:

• At the point of entry: itching and a localized rash where the larvae went into the skin, sometimes called ground itch
• As the larvae pass through the lungs: a cough, in some people
• Once the worms are in the intestine: belly pain, diarrhea, loss of appetite, nausea, gas and weight loss

The most important effect of hookworm is slow blood loss. The worms attach to the intestinal wall and feed on blood, so heavier or longer infections can cause iron-deficiency anemia and protein loss. Signs of anemia include tiredness, weakness, pale skin and shortness of breath on exertion. The CDC notes that in children, ongoing heavy infection can slow physical and mental development.

Is hookworm contagious?

Not directly from person to person. Hookworm does not spread through touching, kissing or sharing a home the way pinworm does. The eggs passed in stool must spend time in warm, moist soil before the larvae can infect anyone. In practice, the risk comes from contaminated ground, not from living with someone who has hookworm, although people in the same household may share the same exposure.

Who is at risk?

The CDC describes hookworm as most common in warm, moist climates where sanitation and hygiene are poor, and among people who walk barefoot or whose skin touches contaminated soil, including children playing outdoors. It is one of the world's most common worm infections, affecting hundreds of millions of people globally.

MedlinePlus notes that the risk of getting hookworm in the United States is very low today because of modern sanitation. If you live in the US, your risk is mainly tied to time spent in tropical or subtropical regions where hookworm is common.

What about hookworm from dogs or cats?

Dog and cat hookworms are different species. The CDC explains that when their larvae burrow into human skin, usually on the feet or legs after contact with sand or soil contaminated by animal waste, they cause cutaneous larva migrans: severe itching and raised red tracks in the skin. These larvae usually cannot complete their life cycle in people, and most people recover without treatment.

That skin condition is not what mebendazole's labeling covers, and it is not treated through Get It Prescribed. If you have an itchy, wandering track on your skin, see a clinician in person.

How hookworm is diagnosed

The CDC states that a stool test, where a lab looks for hookworm eggs under a microscope, is the only way to know for sure that you have a hookworm infection. A clinician may also order a blood count to check for anemia and raised eosinophils, a type of white blood cell that often goes up with parasitic infections. Symptoms alone are not enough to tell hookworm apart from other causes of stomach upset or anemia. Our guide to the stool test for parasites explains how the test works.

How hookworm is treated

Hookworm is treated with prescription anti-worm medicine chosen by a clinician. MedlinePlus lists albendazole and mebendazole among the medicines used. The prescribing information for the brand-name mebendazole chewable tablet includes both human hookworm species, Ancylostoma duodenale and Necator americanus, among its labeled uses, alongside pinworm, roundworm and whipworm. For background on the medicine, see what is mebendazole and how does it work.

Because hookworm causes blood loss, treatment often also addresses the anemia. The CDC notes that people with anemia are often prescribed iron supplements, and a clinician may recommend more protein in the diet.

The dose and length of treatment are the prescriber's decision. We don't publish doses or schedules, and you should follow the directions on your own prescription label. Possible side effects are covered in mebendazole side effects.

Preventing hookworm

• Wear shoes where soil may be contaminated with human waste, especially when traveling in warm regions
• Avoid sitting or lying directly on soil or sand in those areas
• Wash your hands with soap and water after using the toilet and before handling food
• Wash, peel or cook raw fruits and vegetables

Getting hookworm treatment online

If you have been diagnosed with hookworm, or a clinician suspects it based on your history and test results, a licensed provider can review your health assessment through Get It Prescribed and decide whether mebendazole is appropriate. There is a one-time $50 consultation fee, and mebendazole costs $3.50 per capsule; the prescriber decides the quantity. The service is available in all 50 states and the District of Columbia, and some states require a live phone or video visit. How it works shows each step. A prescription is never guaranteed.

The mebendazole dispensed through Get It Prescribed is a compounded preparation made by a licensed compounding pharmacy for an individual patient. Compounded preparations are not FDA-approved, and the FDA does not review them for safety, effectiveness or quality. They are not generics of, or substitutes for, the brand-name product.

See a clinician in person instead if you are pregnant or breastfeeding, have signs of significant anemia such as fainting, a racing heart or breathlessness at rest, see blood in your stool, or are treating a young child.

Related questions

What are the symptoms of hookworm in humans?

Many people have none. When symptoms occur, the first sign is often an itchy rash where the larvae entered the skin. Once the worms reach the intestine, people may have belly pain, diarrhea, loss of appetite and weight loss. Heavier infections cause blood loss, which can lead to iron-deficiency anemia, tiredness and pale skin.

How do humans get hookworm?

Mostly by walking barefoot on soil contaminated with human waste. The larvae burrow through the skin and travel to the small intestine. One species can also infect people when larvae are swallowed. You can't catch it from the eggs directly, because they must hatch and develop in soil first.

Is hookworm contagious from person to person?

No, not directly. Hookworm eggs passed in stool need time in warm, moist soil before the larvae can infect anyone, so it doesn't spread by touch or by sharing a home. People in the same household can still catch it from the same contaminated ground.

What is the treatment for hookworm in humans?

Prescription anti-worm medicine, such as mebendazole or albendazole, chosen by a clinician. People with anemia are often given iron supplements as well. A stool test is the way to confirm the diagnosis.

Can you get hookworm from a dog?

Dog and cat hookworms can burrow into human skin and cause itchy red tracks called cutaneous larva migrans, but they usually can't develop into an intestinal infection in people. It is a different condition from human hookworm, and most cases clear without treatment. See a clinician if you have these skin tracks.

Sources

• CDC: About Hookworm — how people get hookworm, symptoms, risk groups, diagnosis and treatment.
• CDC: About Soil-transmitted Helminths — hookworm, roundworm and whipworm, how they spread and how they are treated.
• CDC: About Zoonotic Hookworm — dog and cat hookworms and cutaneous larva migrans.
• MedlinePlus: Hookworm infection — National Library of Medicine overview, including US risk and treatment.
• MedlinePlus: Mebendazole — consumer drug information from the National Library of Medicine.
• DailyMed: mebendazole chewable tablet prescribing information — labeled uses, including both human hookworm species.
• WHO: Soil-transmitted helminth infections — global background on hookworm and related worms.
• FDA: Compounding and the FDA — Questions and Answers — what compounded preparations are and how they are regulated.