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Related to miracidium: sporocyst, cercariae, Metacercariae, rediae


 [mi″rah-sid´e-um] (Gr.)
the free-swimming larva of a trematode parasite which emerges from an egg and penetrates the body of a snail host.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


, pl.


(mī'ră-sid'ē-ŭm, -ă),
The ciliated first-stage larva of a trematode that emerges from the egg and must penetrate into the tissues of an appropriate intermediate host snail if it is to continue its life cycle; followed by development into a mother sporocyst and by production of a number of offspring of successive larval generations.
See also: sporocyst (1).
[G. meirakidion, boy]
Farlex Partner Medical Dictionary © Farlex 2012


(mîr′ə-sĭd′ē-əm, mī′rə-)
n. pl. miracid·ia (-ē-ə)
A ciliated larva of a digenetic trematode, which hatches from the egg and enters the first intermediate host, where it develops into a sporocyst or a redia.

mi′ra·cid′i·al adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


The first-stage larva of a fluke such as Schistosoma species Fasciolopsis or Chlonorchis species. Miracidia are released into water in human excreta and invade particular water snails in which the second-stage larvae (sporocysts) form. These release thousands of cercariae, the form that can pass through the skin to infect humans.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


(pl. miracidia) the first larval form of a liver- or blood- FLUKE, which develops from the egg as a flat free-swimming, ciliated larva.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

Miracidium (plural, miracidia)

The free-swimming larval form in the life cycle of the liver fluke.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
At the center of granulomas are eggs; some containing a developing miracidium and others are empty eggshells.
The author would like to thank Professor David Dunne, Schistosomiasis Research Group, University of Cambridge, UK (Schistosomule, ova and granuloma) and Professor Alan Wilson, Department of Biology, University of York, UK (miracidium) for permission to reproduce their photographs, which are subject to their own copyright.
Adult worms release eggs that are shed in the bird's feces and upon immersion in water, a miracidium emerges.
During the survey, the Kato-Katz technique and the miracidium hatching test were used for fecal examination.
The eggs undergo a slow development involving a dispersing phase during 10 days before reaching the miracidium stage that infects molluscs.
When temperature and moisture conditions are right, the "miracidium" (a free-swimming larva) hatches from the egg and must locate a snail within a few hours.
On exposure to water, the eggs hatch and liberate a miracidium that infects a suitable molluscan intermediate host.
The microscopic examination of nasal washings revealed boomerang shaped eggs with terminal spine and fully developed miracidium inside (Fig.
The larval stage, known as miracidium, is hatched from the egg in the water and enters the snail host.
Miracidium The larve that emerges from the egg in trematodes.
Praziquantel only kills adult worms and does not inactivate schistosomules, nor the miracidium inside the eggs, which will continue to elicit a damaging immunologic response for some time.