Leeches are blood-sucking creatures with a wormlike appearance. They live in the tropics and temperate zones. Watch out for them when swimming in infested waters or passing through swampy, tropical vegetation and bogs. Leeches are primarily nocturnal, spending daylight hours under rocks, vegetation or debris. At night, they come out and forage on insect larvae, worms and other invertebrates.
Leeches are related to earthworms and marine worms. They are easily recognized: their bodies are ringed with prominent, often circular sucker at the rear, and they have a fixed number (33) of segments. They are common inhabitants of ponds, marshes, lakes, and slow streams, particularly in the northern half of the U.S. Only a few species of leeches can tolerate pollution.
Aquatic and terrestrial leeches have incredible senses of perception. They are attracted by vibration and body heat, and have ten pairs of eyes. Only two of the 25 types of leeches in the U.S. are blood-suckers.
Check yourself frequently for leeches. Don’t burn or squeeze them; they might regurgitate and infect you with bacteria from their digestive system. Get them off by gently sliding your fingernail under the smaller end (the head) and flicking it away.
Leeches can crawl into small openings so avoid camping in their habitats when possible. Keep your trousers tucked in your boots.
Hirudiniasis is a potentially serious condition in which one or more leeches invade a body orifice – and that means all body orifices. And watch out for your air passage, where it may cause a blockage or suffocation, especially if they attach themselves in large numbers. Severe infections from wounds inside the throat or nose can develop when sores from swallowed leeches became infected. If there is a leech invading your airway and you can breath, don’t attempt to remove it—get medical help immediately. If you can’t breathe—reach for the bottle:
1. Gargle with diluted 80-proof alcohol. Most distilled liquors—vodka, gin, bourbon, Scotch—have the right alcohol content. Use a mixture of 50% alcohol, 50% water. Don’t inhale the leech (or the alcohol) as leeches can be a big problem if swallowed or eaten. Treat water from questionable sources by boiling or using chemical water treatments.
They can also live in fresh water turtles, so be careful if that’s what’s on your dinner menu!