World Library  
Flag as Inappropriate
Email this Article

Ancylostoma duodenale

Article Id: WHEBN0003444133
Reproduction Date:

Title: Ancylostoma duodenale  
Author: World Heritage Encyclopedia
Language: English
Subject: Geohelminth, Angelo Dubini, Cutaneous larva migrans, Parasitic disease, Helminths
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Ancylostoma duodenale

Ancylostoma duodenale
Scientific classification
Kingdom: Animalia
Phylum: Nematoda
Class: Secernentea
Order: Strongylida
Family: Ancylostomatidae
Genus: Ancylostoma
Species: A. duodenale
Binomial name
Ancylostoma duodenale

Ancylostoma duodenale is a species of the worm genus Ancylostoma. It is a parasitic nematode worm and commonly known as the Old World hookworm. It lives in the small intestine of hosts such as humans, cats and dogs, where it is able to mate and mature. Ancylostoma duodenale and Necator americanus are the two human hookworms that are normally discussed together as the cause of hookworm infection. They are dioecious.[1] Ancylostoma duodenale is abundant throughout the world, including in the following areas: southern Europe, north Africa, India, China, southeast Asia, some areas in the United States, the Caribbean, and South America.

Contents

  • Characteristics 1
  • Infection 2
  • Notes 3
  • References 4
  • External links 5

Characteristics

Ancylostoma duodenale is small cylindrical worm, greyish-white in color. It has two ventral plates on the anterior margin of the buccal capsule. Each of them has two large teeth that are fused at their bases. A pair of small teeth can be found in the depths of the buccal capsule. Males are 8 mm to 11 mm long with a copulatory bursa at the posterior end. Females are 10 mm to 13 mm long, with the vulva located at the posterior end; females can lay 10,000 to 30,000 eggs per day. The average lifespan of Ancylostoma duodenale is one year.

When a rhabditiform larva "infective" penetrates the intact skin, most commonly through the feet and the larva enters the blood circulation. It is then carried to the lungs, they break into alveoli, ascend the bronchi and trachea and are coughed up, and swallowed back into the small intestine where they mature. The larva later matures into an adult in the small intestine "the adult worm live in the jejunum mainly" where they attach to the villi and female worms can lay 25,000 eggs per day. The eggs are released into the feces and reside on soil, when deposited on warm, moist soil a larva rapidly develops in the egg and hatches after 1-2 days. This Rhabditiform larva moults twice in the soil and become a skin- penetrating 3rd stage infective larva within 5-10 days. The Rhabditiform larvae can then penetrate the exposed skin of another organism and begin a new cycle of infection.

Ancylostoma duodenale is prevalent in southern Europe, northern Africa, India, China, and southeast Asia, small areas of United States, the Caribbean islands, and South America. This hookworm is well known in mines because of the consistency in temperature and humidity that provide an ideal habitat for egg and juvenile development. It is estimated 1 billion people are infected with hookworms. Transmission of Ancylostoma duodenale is by contact of skin with soil contaminated with larvae.

Infection

The Light infection causes abdominal pain, loss of appetite and geophagy. Heavy infection causes severe protein deficiency or iron deficiency anemia. Protein deficiency may lead to dry skin, edema and potbelly, while iron deficiency anemia might result in mental dullness and heart failure.

The eggs of Ancylostoma duodenale and Necator americanus cannot be distinguished. Larvae cannot be found in stool specimen unless they are left at ambient temperature for a day or more.

Education, improved sanitation and controlled disposal of human feces are important. Wearing shoes in endemic areas can reduce the prevalence of infection as well.

Ancylostoma duodenale can be treated with albendazole, mebendazole and benzimidazoles. Pyrantel pamoate is an alternative. In severe cases of anemia, blood transfusion may be necessary.

Notes

  1. ^ "Ancylostoma duodenale". Archived from the original on 1 March 2009. Retrieved 2009-01-22. 

References

  • Hotez, P. J., and D. I. Pritchard. 1995(June). Hookworm infection. Sci. Am. 272:68–74.
  • Looss, A. 1898. Zur Lebensgeschichte des Ankylostoma duodenale. Cbt. Bakt. 24:441–449, 483–488.
  • Murray, P. R., K. S. Rosenthal, and M. A. Pfaller. 2009. Medical Mirobiology, 6th ed. Elsevier/Mosby Publishing Company, Philadelphia, U.S.A., 865 p.
  • Schmidt, G.D., and L. S. Roberts. 2009. Foundations of parasitology, 8th ed. McGraw-Hill Companies, New York,p. 472–473.

External links

  • http://workforce.cup.edu/buckelew/Ancylostoma%20duodenale%20ova.htm
  • Ancylostoma duodenale image library at DPD
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.