What If You Fell Into a Pool of Leeches?

4 min read

Welcome to your worst nightmare. You’ve lost your balance and fell into a pool of slimy parasitic animals that eat only one thing. Your blood. What would happen if you were at the bottom of this pool full of leeches? How many would it take to kill you? What kind of infections would run through your body? And what could happen if you swallowed them?

Let’s get down to it. The usual neighborhood swimming pool measures around 28 cubic m (100 cubic ft). On average, an adult leech measures 3 cm (1.2 in) in length. So to fill this portal to hell, you would need nine million of these parasitic worms. Both ends of these nasty little critters have suckers that attach to the outside of their victim.

Their sharp teeth cut into the flesh in a mark shaped like a Y. Then they pump blood into a pouch within their body, called a crop. A few leeches would be disgusting and mildly annoying. But millions of them crawling all over you, oh geez, give me a minute. If you were surrounded on all sides by these parasites, is there any chance they would just leave you alone?

Now, some leeches don’t even drink blood. Like in the ocean, where leeches tend to leave humans alone. Like me, they prefer sushi. But this is What If. We’re not going to let you off that easy. Some of the land-based species are highly aggressive toward humans, so you falling into this pool might drive them crazy. Your body can contain up to 5.5 L (1.4 gal) of blood.

If you didn’t yank it off, one leech can suck about 15 ml (0.5 oz) in a 40-minute session. So over 1,000 leeches could dry you out like a piece of jerky. If you squeezed the leech as you ripped it off, it could puke blood back into your system. That could leave you with syphilis, hepatitis B or even HIV. If you lose too much blood, you could develop anemia.

At least you wouldn’t be in too much pain. Leeches emit anesthesia to numb your skin as they feast. It also stops your blood from clotting, so you would drip like a faucet into their hungry mouths. Once you lose 30% of your blood, you could start to feel nauseous. Your heart would race as your blood vessels tighten up, restricting the blood flow to your body.

Your skin would become cold and pale, and your arms and legs would be useless. If they kept draining you, the blood loss could cause a hemorrhage. But that might still be better than if these slipped down your throat. The slimy feeling of leeches in your mouth could make you vomit. Keep that thought in your head because if the leeches went down your throat, they could attach themselves inside.

That’s right. They could drain you from the inside out. And if these sleazy suckers emptied you of 40% of your blood, you’d be dead. Considering you’d be in a pool with nine million of them, you probably wouldn’t stand a chance. While some doctors still use leeches today for bloodletting, falling into a pool of them could be fatal.

Even if you managed to crawl out before you lost too much blood, your body might never be the same. But again, maybe you could luck out and fall into one of the varieties of leeches that aren’t interested in turning you into a human buffet.