While worms in humans are a fact of life, it does cause a bit of an uneasy feeling when you find yourself reading about them. They are, however, present in nearly every human being usually in the form of stomach parasites. Perhaps rather than being concerned about the worm though it's better to differentiate between parasites and a parasitic infection. Flatworms, flukes, and roundworms are most responsible for parasitic worm infections, but there are indeed others that can multiply and grow in the human body.
Tapeworm exposure is almost exclusively the result of water contaminated with their eggs, while flatworms are generally introduced to the body through raw or undercooked meat. Flukes usually make their way into your system through freshwater plants like greens and watercress. Hookworms make their way into your intestines from contaminated soil and feces. Pinworms usually affect children and are relatively harmless by cause anal itching owing to egg planting at night. Trichinosis worms are not common these days but can still be transmitted through undercooked meat. They mainly call the intestines home but can burrow their way into muscle and tissue in extreme cases. While worms produce a myriad of symptoms, some are considerably more common than others.
While not necessarily a symptom per se, those that are just back from a trip to foreign lands where hygiene may be lacking can question if they brought something back with them as a number of these symptoms begin manifesting themselves. Again, everyone has worms nearly all the time, but these are the types of worms that often leave to infections given prolonged exposure to less than hygienic conditions and contaminated water.
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