A type of bloodsucking worm with a flattened body and a sucker at each end. Leeches of various types inhabit tropical forests and waters. They bite painlessly, introducing their saliva into the wound before sucking blood. Leech saliva contains an anticlotting substance called hirudin, which may cause the wound to bleed for hours. Leeches are sometimes used in medicine to drain a haematoma from a wound.
A blood-feeding annelid worm.
n. a type of worm that possesses suckers at both ends of its body. Leeches occur in tropical forests and grasslands and in water. Certain parasitic species suck blood from animals and humans, and their bites cause irritation and, in some cases, infection. A leech can be detached from its host by applying salt. Formerly widely used for letting blood, the medicinal leech (Hirudo medicinalis) may now be used following microsurgery (e.g. to replace a severed finger) to restore patency to blocked or collapsed blood vessels and thus encourage the growth of new capillaries. The anticoagulants in the saliva of this and other species are now used for the treatment and prevention of thrombosis (see hirudin).
Animals provided with suckers surrounding the mouth, and living a semi-parasitic life, their food being mainly derived from the blood of other animals. They abstract blood by means of the sucker, which has several large, sharp teeth. Land leeches live in tropical forests and can attach themselves to a person’s ankles and lower legs. Aquatic leeches are found in warm water and may attach themselves to swimmers. Their bites are painless, their saliva reducing the clotting properties of blood with hirudin; the result is that the wound continues to bleed after the leech has detached itself or been gently removed (lighted match, alcohol, salt and vinegar are e?ective removal agents). The medicinal leech, Hirudo medicinalis, was formerly employed for the abstraction of small quantities of blood in in?ammatory and other conditions. Nowadays it is occasionally used to drain haematomas and to manage healing in certain types of plastic surgery.... leeches
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