Several types of worm, or their larvae, existing as parasites of humans. They may live in the intestines, blood, lymphatic system, bile ducts, or in organs such as the liver. In many cases, they cause few or no symptoms, but some can cause chronic illness. There are 2 main classes: roundworms and platyhelminths, which are subdivided into cestodes (tapeworms) and trematodes (flukes). Worm diseases found in developed countries include threadworm infestation, ascariasis, whipworm infestation, toxocariasis, liver-fluke infestation, and various tapeworm infestations. Those occurring in tropical regions include hookworm infestation, filariasis, guinea worm disease, and schistosomiasis. Worms may be acquired by eating undercooked, infected meat, by contact with soil or water containing worm larvae, or by accidental ingestion of worm eggs from soil contaminated by infected faeces. Most infestations can be easily eradicated with anthelmintic drugs.
Worm infestation |
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