ISSN 2398-2950      

Ancylostoma braziliense

ffelis
Contributor(s):

Maggie Fisher

Ian Wright

Synonym(s): A. braziliense, Hookworm


Introduction

Classification

Taxonomy

  • Superfamily: Ancylostomatoidea.
  • Family: Ancylostomatidae.
  • Genus: Ancylostoma.
  • Species: braziliense.

Active Forms

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Resting Forms

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Clinical Effects

Epidemiology

Habitat

  • Adults in small intestine.
  • Egg in environment. Eggs develop to L3 in warm and moist environment.
  • L3 infect animal by direct penetration of skin or through larval ingestion by the host.
  • Adult worms mature and shed eggs in small intestine.

Lifecycle

  • A. braziliense eggs are passed in the feces. First stage larva (L1) develops, the egg hatches and eventually infective L3 develop in humid and warm soil. Infection takes place by percutaneous penetration of the skin and passage of the larvae through the blood circulation, penetration of the lung alveoli, coughing the larvae into the trachea, and swallowing of the worms into the small intestine where they attach to the intestinal wall and develop as adults. Oral transmission by direct swallowing of L3 or ingestion of an infected paratenic host is also possible. Ingested larvae enter the stomach or intestinal wall where they molt to L4 and then return to the lumen where they mature. Transmammary transmission has not been described for A. braziliense or A. tubaeforme Ancylostoma tubaeforme. The prepatent period varies between 2-4 weeks and is longer for percutaneous transmission than for the oral route of infection.

Transmission

  • Infection can occur via L3 in the environment, or via infected paratenic hosts. Skin penetration is also known to occur. Transplacental transmission has not been demonstrated with this species of AncylostomaA. braziliense has been shown to effect skin penetration more rapidly than A. caninum or A. celyanicum.
  • Percutaneous penetration of L3; oral infection with L3 or ingestion of paratenic host.

Pathological effects

  • Older animals develop a protective immunity to hookworms and are less likely to develop clinical signs of infection.
  • A. braziliense, like other hookworms, can cause anemia because of its blood-feeding  activities. However, A. braziliense is considered to consume relatively less blood than some other hookworms (5 ml per day per worm compared with 43 ml per worm per day for Ancylostoma caninum).

Other Host Effects

  • A. braziliense occurs in dogs, cats and foxes. In comparison to A. caninum, it is not considered a good blood-sucker and is therefore of less pathogenic importance and does not induce severe anemia. A braziliense infection may cause loss of protein through intestinal leak of serum proteins manifesting as hypoproteinemia in affected animals. Mild gastrointestinal signs including diarrhea may also be seen.

Host interaction

  • While primarily a parasite of dogs and wild canids, A. braziliense can also infect felids, and is a relatively common cause of cutaneou slarva migrans in man. Strain differences may exist between worms with tropisms for dogs and cats. Clinical signs, including anemia, stunted growth and weight loss are most commonly seen in kittns and young adult cats. Light or moderate infections in adult cats are relatively well-tolerated.
  • The potential of A. braziliense to penetrate skin is attributed to the production and secretion of hyaluuronidase and other enzymes. Blood feeding is facilitated by the secretion of anticoagulants.
  • Mild diarrhea caused by feeding of L4 and adults on the intestinal mucosa and loss of protein.
  • Dermatitis due to larval invasion of the skin, in particular the feet may occur.
  • A braziliense, in common with some other hookworms of domestic animals, can cause cutaneous larva migrans  Visceral larva migrans ("creeping eruption") in man. This species is thought to be one of the main causes of this zoonosis in many tropical /sub-tropical areas. There are also occasional reports of intestinal infection of man with A. braziliense.  However, generally, man is considered as a "dead end host". The lesions observed following skin penetration, in man and pets, are similar with inflammation, vesicle formation, eosinophil accumulation, and crusting.
  • A. braziliense has a mainly tropical, sub-tropical distribution. A number of small surveys give an indication of its overall prevalence. For example, it was found in 19% of stray dogs in Blomfontein, South Africa, 20% of stray dogs in Gauteng, South Africa, 49% in Tacuarembo, Uruguay.
  • The main importance of A. braziliense is its zoonotic potential. It is regarded as a major cause of cutaneous larva migrans (CLM) in humans. The infective larvae penetrate the skin and migrate through the dermis causing tortuous erythematous inflammtory tracts with a severe itch that may persist for weeks. CLM is commonly associated with infection from larvae originating in sand or at the beach in endemic countries.

Control

Control via chemotherapies

Control via environment

  • Where cats are housed together measures to avoid fecal contamination of food and water, regular removal of feces and cleaning of litter trays will help to break the cycle of infection. Infected surfaces and soil may be disinfected cautiously with sodium borate, which is also toxic to plants. Predation on possible paratenic hosts such as rodents should be stopped.
  • Regular anthelmintic preventative measures include deworming every 3 months.

Diagnosis

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Prullage J B, Knaus M, Bowman D D et al (2014) Efficacy of a novel topical combination of fipronil, (S)-methoprene, eprinomectin and praziquantel against induced infections of Ancylostoma spp. nematodes of cats. Vet Parasitol 202 (1-2), 30-33 PubMed.
  • Liotta J L, Koompapong K N, Yaros J P et al (2012) Prevalence of Ancylostoma braziliense in cats in three northern counties of Florida, United States. J Parasitol 98 (5), 1032-1033 PubMed
  • Lucio-Forster A, Liotta J L, Yaros J P et al (2012) Morphological differentiation of eggs of Ancylostoma caninumAncylostoma tubaeforme, and Ancylostoma braziliense from dogs and cats in the United States. J Parasitol 98 (5), 1041-1044 PubMed.
  • Traub R J, Robertson I D, Irwin P et al (2004) Application of a species-specific PCR-RFLP to identify Ancylostoma eggs directly from canine faeces. Vet Parasitol 123 (3-4), 245-255 PubMed.
  • Brenner M A & Patel M B (2003) Cutaneous larva migrans: the creeping eruption. Cutis 72 (2), 111-115 PubMed.
  • Shoop W L, Michael B F, Soll M D et al (1996) Efficacy of an ivermectin and pyrantel pamoate combination against adult hookworm, Ancylostoma braziliense, in dogs. Aust Vet J 73 (3), 84-85 PubMed.

Other sources of information

  • Ballweber L R (2001) Parasites of the Gastrointestinal Tract 1. In: The practical veterinarian - Veterinary Parasitology. Boston, Mass: Butterworth Heinemann. pp 137-145.
  • Bowman D D (1999) Helminths. In: Georgis' Parasitology for Veterinarians. 7th edn. Philadelphia, PA. W B Saunders. pp 178-184.
  • Urquhart G M, Armour J, Duncan J L, Dunn A M, Jenning F W (eds) (1996) Veterinary helminthology. In: Veterinary Parasitology.Oxford, UK. Blackwell Science. pp 53-56.
  • Soulsby E J L (1982) Helminths, Arthropods and Protozoa of Domesticated Animals. 7th Edn. Ballière Tindall, London.

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!