Journal of Veterinary Medicine and Allied Science

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Editorial - Journal of Veterinary Medicine and Allied Science (2021) Volume 5, Issue 2

Pathogenicity of Echinococcus granulosus in animals

Veena Priyadarshini S *

School of Life Sciences, B.S. Abdur Rahaman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India

*Corresponding Author:
Veena Priyadarshini S
School of Life Sciences
B.S. Abdur Rahaman Crescent Institute of Science and Technology, Chennai, Tamil Nadu, India
Tel: 9500084421r> E-mail:

Received Date: September 17, 2021; Accepted Date: September 28, 2021; Published Date: September 30, 2021

Citation: Veena Priyadarshini S (2021)Pathogenicity of Echinococcus granulosus in animals . J Vet Med Allied Sci 2021 Volume 5 Issue 2: 1.

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Infection with Echinococcus granulosus (cystic echinococcosis, hydatid illness) or Echinococcus multilocularis larvae causes echinococcosis (alveolar disease). The symptoms of liver cysts include jaundice and stomach discomfort, whereas lung cysts cause cough, chest pain, and hemoptysis. Fever, urticaria, and severe allergic responses can all result after cyst rupture. Imaging, cyst fluid investigation, and serologic testing are used to make a diagnosis. Dogs are the definitive hosts, with mature tapeworms in their gastrointestinal tracts, whereas herbivores (such as sheep, horses, and deer) or humans are intermediate hosts, developing cystic lesions in the liver or other organs, and are found in Canada, Alaska, and California.

Foxes, coyotes, and dogs have adult E. multilocularis worms, while tiny wild rodents have hydatid larvae. Infected dogs are the main source of infection in humans. Central Europe, Alaska, Canada, and Siberia are the major habitats for E. multilocularis. Natural infection ranges from Wyoming and the Dakotas to the upper Midwest in the continental United States.

Hydatid disease is caused by Echinococcus vogelii or Echinococcus oliganthus in humans on a rare occasion, especially in the liver. The infection might be polycystic (E. vogelii) or unicystic (E. vogelii) (E. oliganthus). These animals may be found throughout Central and South America.


Animal feces eggs (which may be found on the fur of dogs or other animals) are ingested and hatch in the stomach, releasing oncospheres (immature forms of the parasite enclosed in an embryonic envelope). Oncospheres pass through the intestinal wall, migrate via the bloodstream, and settle in the liver or lungs, or, less commonly, the brain, bone, or other organs. Adult worms are not seen in the human gastrointestinal tract. Oncospheres of E. granulosus develop into cysts in tissue, which expand slowly (over many years) into enormous unilocular, fluid-filled tumors known as hydatid cysts. Within these cysts, brood capsules containing many tiny infective protoscolices develop. Large cysts can contain millions of protoscolices as well as 1 liter of highly antigenic hydatid fluid. Daughter cysts can develop inside or outside of parent cysts.

Infection can spread to the peritoneum if a cyst in the liver leaks or ruptures. Spongy masses are produced by E. multilocularis, which are locally invasive and difficult or impossible to cure surgically. Cysts are most found in the liver, although they can also be found in the lungs or other organs. Although the cysts are small, they can infiltrate and kill surrounding tissue, resulting in liver failure and death.

Transmission from animals to humans

Cystic Echinococcus is caused by the Metacestode stage of E. granulosus, which is a cystic formation filled with clear fluid (hydatid fluid). The Meta cestode is a tiny vesicle with an interior cellular layer (germinal layer) and an outside acellular, laminated layer that forms around 5 days after egg ingestion. This cyst (endocyst) grows over time, triggering a granulomatous host reaction, followed by a fibrous tissue reaction and the development of a connective tissue layer (peri cyst). Cysts in the human body can range in size from 1 to 15 cm in diameter, but they can sometimes be considerably bigger (>20 cm in diameter).

The exact time it takes for protoscoleces to form within cysts in the human host is unknown, although it is estimated to be more than 10 months after infection. Protoscoleces can be produced in cysts with a diameter of 5 to 20 mm (149); however, some cysts do not develop protoscoleces and remain "sterile." Most of the cysts are univesicular (i.e., unilocular), however smaller daughter cysts can develop within larger mother cysts in certain cases. Although the two species coexist in broad regions of endemic infection, mixed infections with E. granulosus and E. multilocularis metacestodes are uncommon

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