Angiostrongylus		Contents		Rev 09/21/2024
Lungworms and Heartworms		Classification		Biology and Ecology
		Morphology and Anatomy		Life Cycle
Return to Angiostrongylus Menu				Ecosystem Functions and Services
		Distribution		Management
Return to Angiostrongylidae Menu		Feeding		References
		Go to Nemaplex Main Menu		Go to Dictionary of Terminology

Classification:

Chromadorea

  Rhabditia

    Rhabditida

      Metarongyloidea

        Angiostrongylidae

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Morphology and Anatomy:

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Distribution:

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Feeding:

 Snails are intermediate hosts of many species while rats, domestic dogs and wild mammals and other vertebrates are the definitive hosts (Souza et al., 2009)..

Accidental infections of humans somwetimes occur, resulting in characteristic clinical symptoms (Wand et al., 2008)

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Biology and Ecology:

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Life Cycle:

Proposed life cycle of Angiostrongylus vasorum, canine heartworm,  as an example:  (a) First-stage larvae (L1) are passed out in the faeces of the final host. The prepatent period is around 40–60 days, and larvae are reputedly egested for many years after infection, and possibly for the lifetime of the final host. (b) L1 larvae infect molluscan intermediate hosts either by ingestion while foraging on faeces or by penetration through the epidermis.  (c) Intermediate host: several species of slug and snail have been infected experimentally but it is not really known which species are most important in nature. Larvae develop in the intermediate host, moulting twice to reach the third stage (L3) after about 16 days.  (d) The common frog (Rana temporaria) can act as a paratenic host after ingestion of infected slugs or snails, and as an intermediate host after experimental infection with L1.  (e) L3 are ingested by the final host, either with an infected gastropod, possibly food contaminated with snail or slug secretion (slime) containing L3 larvae, or a paratenic host.  (f) Final host: the fox and dog (and possibly also other wild canids and mustelids) are final hosts. After ingestion, L3 penetrate the gut and migrate to abdominal lymph nodes, where the third and fourth moults take place. The early L5 then enter the portal circulation and migrate through the liver to reach the right ventricle and pulmonary arteries, where they develop to the adult stage. The female is oviparous and eggs are carried in the bloodstream to the pulmonary capillaries. The eggs hatch and L1 penetrate into the alveoli, migrate to the pharynx and are swallowed, to pass out in the faeces 1, 6.

Adapted from Morgan et al.(2005)

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Ecosystem Functions and Services:

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Management:

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References:

Morgan, E.R., Shaw. S.E., Brennan, S.F., De Waal, T.D., Jones, B.R., Mulcahy, G. 2005. Angiostrongylus vasorum: a real heartbreaker. Trends in Parasitology 21:49-51.

Souza, J.G.R., Simoes, R.O., Thiengo, S.A.R.C., Lima, W.S., Muta, E.M., Rodrigues-Silva, R., Lanfredi, R.M., Maldonado, A. 2009. A new metastrongylid species (Nematode: Metastrongylidae): a lungworm from Akodon montensis (Rodentia: Sigmodontinae) in Brazil.  J. Parsitol 95:1507-1511.

Wang, Q-P., Lai, D.H., Zhu, X.Q., Chen, X.G., Lun, Z.R. 2008. Human angiostrongyliasis. The Lancet (Infectious Diseases) 10:621-630.

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Copyright © 1999 by Howard Ferris.
Revised: September 21, 2024.

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