What If You Covered Your Body in Leeches? | Unveiled

What If Your Body Was Covered in Leeches?

In the last century, we’ve made incredible advances in medicine. We understand more about diseases and how to fight them than ever before and have long since abandoned some of history’s strangest health procedures. But one treatment remains perhaps the most infamous of them all…

This is Unveiled, and today we’re answering the extraordinary question; what if your body was covered in leeches?

There are plenty of circumstances where you could find yourself treating a leech bite; circumstances which don’t involve a misguided doctor trying to fix a common ailment. After all, these parasitic worms exist on every continent in the world except Antarctica, and they’re hungry... with certain types of leech even classified as “predators”, rather than simple “parasites”, in some parts of Southeast Asia and South America.

Historically though, leeches gained their popularity in eighteenth and nineteenth century Europe as a less-invasive way to carry out bloodletting. For at least two thousand years, bloodletting was one of the most common medical treatments practiced, seen as a cure-all way to fix almost any issue. And, prior to the application of leeches, the only way to go about it was to use a surgical knife, or lancet, to cut a patient open - which could make things much worse thanks to horrific infection rates and/or massive blood loss. Compared to the ancient ways, then, the use of leeches was at first seen as a major improvement.

Bloodletting, in general, was done because it was thought the human body contained four “humors” – the bodily fluids blood, phlegm, black bile, and yellow bile – and that these “humors” had to be kept in “balance. Any illness which caused redness of the skin (like fever and inflammation; common symptoms of all kinds of ailments), was thought to happen because there was too much blood in the body, so the excess needed to be released to restore balance. Ultimately, thanks to the vast number of conditions it was once thought to help, “leeching” became so popular in the 1800s that there were desperate shortages of the medicinal leech across Europe… and the so called “leech craze” led to a “leech rush”, which demanded that special “leecheries” were built to farm these indispensable bloodsuckers.

But just because we don’t use bloodletting anymore, it’s not like the prospect of getting bitten by a leech isn’t there; wild leeches exist all over the planet, so how dangerous are they really? Well, the biggest danger a single leech poses isn’t usually the amount of blood it alone takes from you; it’s the anticoagulants in its saliva which prevent your blood from clotting. The anticoagulants mean that when a leech gets full and drops off your body, which only takes around thirty minutes on average, you can continue to bleed for hours afterwards because chemicals in the wound prevent it from scabbing over.

Unless you have a pre-existing medical condition, like haemophilia, one or two leech bites like this probably won’t cause lasting harm as long as you clean and dress them properly… But, were you to end up with a lot of them - from wading through a leech-infested river or hiking through the rainforest, for example - then you could need medical attention, and quickly. Multiple bites have been found to cause, among other things, severe anaemia… but, were you to cover your entire body in leeches, then it is most likely the sustained blood loss would kill you long before anything else had the chance. One leech couldn’t possibly take enough blood, but multiple leeches could. And you only need to lose fifteen percent of your blood to start having problems. Once you pass twenty percent blood loss, then you’re at major risk of suffering hypovolemic shock - where the blood that remains isn’t passed around your body quickly enough, potentially leading to multiple organ failure. So much for “balancing the humors”, then!

That said, there are other, perhaps even more prominent dangers that leeches pose; ones where just one, unfortunate bite could cause you a serious problem. A leech retains the bacteria from any of its previous feeds inside its gut, which means it can get into your wound and into your system whilst that leech is feeding on you. In the “best case” worst case scenario we’re talking some kind of infection like chromoblastomycosis, but you can also contract deadlier diseases this way – although it is rare.

For this reason, it’s vital that if you ever do find a leech on you, you need to stay calm and remove it properly. The bacteria from its gut gets into your body if (or when) the leech effectively vomits it up… So, pulling it off as hard as you can might get rid of it, but it’s also much more likely to trigger this regurgitative reaction. Instead, general advice is that you should push something thin like your fingernail or a credit card underneath the leech’s mouth to more carefully break the seal the jaw forms with your skin, at which point you can pull it off more safely. Or, if you’re really brave (and confident that the leeching itself won’t cause you harm) you could just wait for it to finish and drop off on its own accord. However, while it’s not common, it is possible to be allergic to leech bites… making anaphylaxis one of the most severe and life-threatening outcomes to leeching there is… so, it never pays to take the risk!

Gruesomely, it’s not only the outside of your body that leeches might latch onto – with many leech types preferring your insides. The thought of leeches clinging to what are known as “mucous membranes” lining your internal cavities and organs may be enough to literally and figuratively “turn your stomach”, but these creatures have been known to get stuck inside people’s noses, throats and eyes, among other orifices, in search of a tasty snack. If nothing else, you’re then also in danger of having an airway obstructed… and leeches have suffocated their victims before. The prospect of removing leeches from your insides doesn’t sound all too great, either… but it can be safely and swiftly done.

If, then, your entire body really was covered in these things, but you managed to remove them all before succumbing to the blood loss, then potential complications like these would then be the most pressing. Such rapid removal could well have resulted in bacterial infection or illness via any one of your bites… or a stray leech might well have escaped from your skin to your insides to cause yet more trouble.

All things considered, it’s perhaps a little surprising that the European medicinal leech is still going strong today, and that “leech therapy” is a treatment you can have (classed as a form of “biosurgery”). But leeches certainly aren’t used for bloodletting, these days. Instead, they’re sometimes an option post-reconstructive surgery to help keep damaged tissue alive. For example, if you’re in an accident and lose something like a finger or an ear, and it’s possible to reattach what you lost, then leech therapy helps regulate the blood flow at whatever part of your body you’re reattaching it to… improving your chances of a full reconstruction and recovery.

Today, there are facilities which specifically breed leeches to be sterile and safe… in many ways the idea isn’t that different from the “leecheries” of the nineteenth century, but the modern day labs are infinitely more informed, controlled and hygienic. Consider that other biosurgical procedures include “larval debridement therapy” (otherwise known as “maggot therapy”), a treatment for gangrene where maggots eat the dead flesh, and leeches might not even seem that bad. Thankfully, though, we might not need to breed them at all before long, and that’s due to scientists currently working on mechanical leeches - a health technology where small devices attach to wounds and distribute synthesized hirudin, which is the stuff in leech saliva carrying that all-important anticoagulant. Mechanical leeches, then, could soon be able to do the same job without making your skin crawl.

Even so, if you ever were covered head-to-toe in a bloodsucking species of natural leeches, then the outlook still wouldn’t be good. You’d most likely die within a few hours due to sustained blood loss, but if you somehow managed to get them off quickly enough then your frantic removal will most likely have triggered severe infection. If not, then any number may have escaped to your insides. And that’s what would happen if your body was covered in leeches.