Click here to return to the LMHS Home Page

 

Print-Friendly
Bookmarks

Hookworm

 

Hookworm infection is a condition caused by roundworms that affects the small intestine and lungs.

The disorder is caused by infestation with the following roundworms:

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

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

Hookworm disease is common in the moist tropics and subtropics. It affects about 1 billion people worldwide. 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 where people who have hookworm have made feces.

The larvae (immature form of the worm) get into the skin. The larvae move to the lungs via the bloodstream and enter the airways. The worms are about 1/2 inch long.

After traveling up the windpipe, the larva 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. Adult worms and larvae are released in the feces.

Symptoms

 

  • Abdominal discomfort
  • Cough
  • Diarrhea
  • Fatigue
  • Fever
  • Gas
  • Itchy rash
  • Loss of appetite
  • Nausea, vomiting
  • Pale skin

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

 

Exams and Tests

 

Tests that can help diagnose the infection include:

  • Complete blood count (CBC) with differential
  • Stool ova and parasites exam

This disease may also affect the results of a D-xylose absorption test.

 

Treatment

 

The goals of treatment are to:

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

Parasite-killing medications such as albendazole, mebendazole, or pyrantel pamoate are usually prescribed. Ivermectin, used for other worm infections, does not work for hookworm infections.

Symptoms and complications of anemia are treated as they arise. The doctor 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

 

  • Iron deficiency anemia caused by loss of blood
  • Nutritional deficiencies
  • Severe protein loss with fluid buildup in the abdomen (ascites)

 

When to Contact a Medical Professional

 

Call for an appointment with your health care provider if symptoms of hookworm infection develop.

 

Prevention

 

Handwashing and wearing shoes will reduce the likelihood of infection.

 

 

References

Kazura JW. Nematode infections. In: Goldman L, Ausiello D, eds. Goldman's Cecil Medicine. 23rd ed. Philadelphia, PA: Saunders Elsevier; 2007:chap 378.

Maguire JH. Intestinal nematodes (roundworms). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Disease. 7th ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2009:chap 287.

BACK TO TOPText only

 
  • Hookworm - mouth of the organism

    Hookworm - mouth of the ...

    illustration

  • Hookworm - close-up of the organism

    Hookworm - close-up of t...

    illustration

  • Hookworm - Ancylostoma caninum

    Hookworm - Ancylostoma c...

    illustration

  • Hookworm egg

    Hookworm egg

    illustration

  • Hookworm rhabditiform larva

    Hookworm rhabditiform la...

    illustration

  • Digestive system organs

    Digestive system organs

    illustration

    • Hookworm - mouth of the organism

      Hookworm - mouth of the ...

      illustration

    • Hookworm - close-up of the organism

      Hookworm - close-up of t...

      illustration

    • Hookworm - Ancylostoma caninum

      Hookworm - Ancylostoma c...

      illustration

    • Hookworm egg

      Hookworm egg

      illustration

    • Hookworm rhabditiform larva

      Hookworm rhabditiform la...

      illustration

    • Digestive system organs

      Digestive system organs

      illustration

    Tests for Hookworm

     
       

      Review Date: 9/1/2013

      Reviewed By: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.

      The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
      adam.com

       
       
       

       

       

      A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.