Hookworm infection

  • Definition
    • Hookworm infection is caused by roundworms. The disease affects the small intestine and lungs.

  • Alternative Names
    • Hookworm disease; Ground itch;  Ancylostoma duodenale infection; Necator americanus infection; Parasitic infection - hookworm

  • Causes
    • The infection is caused by infestation with any of the following roundworms:

      • Necator americanus
      • Ancylostoma duodenale
      • Ancylostoma ceylanicum
      • Ancylostoma braziliense

      The first 2 roundworms affect humans only. The last 2 types also occur in animals.

      Hookworm disease is common in the moist tropics and subtropics. In developing nations, the disease leads to the death of many children by increasing their risk for infections that their bodies would normally fight off.

      There is very little risk of getting the disease in the United States because of advances in sanitation and waste control. The important factor in getting the disease is walking barefoot on ground where there are feces of people who have hookworm.

      The larvae (immature form of the worm) enter the skin. The larvae move to the lungs via the bloodstream and enter the airways. The worms are about one half inch (1 centimeter) long.

      After traveling up the windpipe, the larvae are swallowed. After the larvae are swallowed, they infect the small intestine. They develop into adult worms and live there for 1 or more years. The worms attach to the intestinal wall and suck blood, which results in iron deficiency anemia and protein loss. Adult worms and larvae are released in the feces.

  • Symptoms
    • Symptoms may include:

      Most people have no symptoms once the worms enter the intestines.

  • Exams and Tests
  • Treatment
    • The goals of treatment are to:

      • Cure the infection
      • Treat complications of anemia
      • Improve nutrition

      Parasite-killing drugs such as albendazole, mebendazole, or pyrantel pamoate are often prescribed.

      Symptoms and complications of anemia are treated, if needed. The health care provider will likely recommend increasing the amount of protein in your diet.

  • Outlook (Prognosis)
    • You will have a complete recovery if you get treated before serious complications develop. Treatment gets rid of the infection.

  • Possible Complications
    • Health problems that may result from hookworm infection include:

  • When to Contact a Medical Professional
    • Call for an appointment with your provider if symptoms of hookworm infection develop.

  • Prevention
    • Handwashing and wearing shoes will reduce the likelihood of infection.

  • References
    • Diemert DJ. Intestinal nematode infections. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 357.

      Hotez PJ. Hookworms (Necator americanus and Angylostoma spp.). In: Kliegman RM, Stanton BF, St. Geme, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2016:chap 292.