Ascaris
| Ascaris | ||||||||||
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Female of the roundworm ( Ascaris lumbricoides ) |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Ascaris | ||||||||||
| Linnaeus , 1758 |
The roundworms ( Ascaris ) are a genus of nematodes (Nematoda), which in general is also known under the collective term ascarids . The best known representatives are the roundworm ( Ascaris lumbricoides ) and the pig roundworm ( Ascaris suum ).
Features and way of life
The worms live in the intestines and grow to 40 cm long, with the males being smaller than the females. It is transmitted through contact with the feces in which the eggs and larvae are located. After oral ingestion of the eggs, e.g. B. via unwashed hands, food or contaminated drinking water, the larvae hatch in the small intestine of their host and migrate via the blood vessels to the liver and lungs . The larvae are coughed up from the lungs and swallowed again. This process is called "tracheal migration". Once in the intestine again, the larvae then develop into adult worms. In pregnant women, the larvae can be transferred to the child via the placenta . A possible infestation can be diagnosed by examining the faeces ( flotation method). The lifespan of roundworms is a year or longer, the eggs can remain infectious for years under favorable conditions in nature.
swell
- H. Mehlhorn, G. Piekarski: Outline of parasite science. 6th edition. Heidelberg 2002.