Speaker 1: Welcome to How Stuff Works. Now. I'm your host, Lauren Vogelbaum,
Speaker 1: a researcher and writer. Here's how Stuff Works. Every week
Speaker 1: I'm bringing you three stories from our team about the
Speaker 1: weird and wondrous advances we've seen in science, technology, and culture,
Speaker 1: except when I don't. This week, we've got just one
Speaker 1: story for you, but it's a longer one, so don't worry.
Speaker 1: If you're driving, you've still got about the same amount
Speaker 1: of time before you have to fiddle with your phone again.
Speaker 1: This one is from staff writer and editor Joe McCormick,
Speaker 1: who's also the co host of a compatriot podcast of ours,
Speaker 1: Stuff to Blow Your Mind. Joe wanted to know how
Speaker 1: and what happens when a human swallows a leech, which
Speaker 1: is a thing that happens more often than you'd like
Speaker 1: to thank, which, to be fair, is more often than never.
Speaker 1: So come along as Joe explores the historical and modern
Speaker 1: cases of leech endo parasitism. Here's what happens when you
Speaker 1: swallow a leech. In surgeon Lieutenant T. A. Granger of
Speaker 1: the British Indian Army wrote a letter to the British
Speaker 1: Medical Journal to report a stomach turning case of parasite
Speaker 1: infestation he encountered at his colonial outpost. While working at
Speaker 1: a fort in the Northwest Provinces of India, Granger received
Speaker 1: a letter from an officer asking for his help with
Speaker 1: an unusual medical complaint. According to the note, a local
Speaker 1: man had a leech attached to the inside of his throat.
Speaker 1: At first, Granger assumed it couldn't be true. Nevertheless, he
Speaker 1: agreed to see the patient. The person he encountered was,
Speaker 1: by Granger's account, an elderly pashtooned man with a gray beard.
Speaker 1: When Granger came within sight, the old man immediately spat
Speaker 1: out a heavy mouthful of thick, blackened blood, presumably to
Speaker 1: demonstrate that his complaint was real. With the help of interpreters,
Speaker 1: Granger questioned the man to learn about his condition. According
Speaker 1: to his story, eleven days previous, the old man had
Speaker 1: been drinking out of a rainwater tank when he suddenly
Speaker 1: felt something catch in his throat. When he tried to
Speaker 1: cough it up, he couldn't. Then the thing caught in
Speaker 1: his throat began to move. He had difficulty swallowing and
Speaker 1: felt like he was going to choke on the writhing
Speaker 1: obstruction it caused him to vomit and to spit up
Speaker 1: blood repeatedly. When Granger first looked inside the old man's throat,
Speaker 1: he was able to remove a clot of blood, but
Speaker 1: couldn't see any parasite. If it was there, it had
Speaker 1: to be deeper. So the surgeon Lieutenant produced a pair
Speaker 1: of polypus forceps, essentially very long tweezers with scissor handles,
Speaker 1: and reached into the hidden depths of the man's lower farynx,
Speaker 1: near the esophagus they are. He detected the presence of
Speaker 1: an object, and through the metal of his instrument, Granger
Speaker 1: could feel it moving. With the tips of the four steps,
Speaker 1: he grabbed hold of the squirming object and with considerable force,
Speaker 1: pulled it out. Indeed, it was a leech between two
Speaker 1: point five and three inches or about six and a
Speaker 1: half to seven and a half centimeters long, with a
Speaker 1: body shaped like the three oh three inch ammunition the
Speaker 1: British infantry used in their lee Metford rifles. A slimy,
Speaker 1: writhing rifle cartridge engorged with human blood had been living
Speaker 1: in this man's throat for eleven days. Granger's letter to
Speaker 1: the b MJ doesn't go on to report what happened
Speaker 1: to the old man, But after an experience like this,
Speaker 1: one would at least hope the worst moment in the
Speaker 1: man's life was behind him. When it comes to leeches
Speaker 1: in the throat, Granger's report is not an isolated incident.
Speaker 1: Granger himself heard stories of other cases like this in
Speaker 1: neighboring towns, and this phenomenon is by no means limited
Speaker 1: to nineteenth century India. Getting a leech attached to the
Speaker 1: inside of a body cavity is common enough that there
Speaker 1: are special medicalized terminologies for it, such as leech indo
Speaker 1: parasitism or internal hierodoniasis. These are phrases most of us
Speaker 1: would probably rather not have in our vocabulary, but even today,
Speaker 1: in the twenty first century, people still show up at
Speaker 1: hospitals around the world with leeches stuck inside their throats.
Speaker 1: Strictly speaking, the leeches a worm phylum Analyta subclass heroudonea,
Speaker 1: from which we get the word hierudoniasis, which refers to
Speaker 1: the condition of being parasitized by a leech. Leeches have
Speaker 1: segmented bodies imagine rings like an earthworm, and suckers at
Speaker 1: both ends. One large sucker at the rear of the
Speaker 1: body used crawling and leverage, and a smaller sucker at
Speaker 1: the front containing the jaws and the mouth. Not all
Speaker 1: leeches are blood drinkers. Some scavenge for detritus, some are
Speaker 1: predatory hunters. But the leech we know best is that
Speaker 1: vampiric parasite that clamps onto the larger host and steadily
Speaker 1: drains all the blood it can, often until the leech's
Speaker 1: body is swollen to around ten times its original size.
Speaker 1: In the wild, leeches drink from all manner of hosts, mammals, fish,
Speaker 1: and amphibians. When a leech bites, it makes a y
Speaker 1: shaped incision in the skin with three curved jaws covered
Speaker 1: in serrated teeth like tiny circular saws, and then extracts
Speaker 1: blood with a muscular sucking action. The saliva of the
Speaker 1: leech is known to contain a cocktail of chemicals to
Speaker 1: ease the process, including heroudin, a polypeptide that prevents blood
Speaker 1: from clotting. Leeches are classically known as external parasites, drawing
Speaker 1: their liquid diet through the outer skin of the host,
Speaker 1: but given the ratunity, they will feed from internal surfaces
Speaker 1: as well, such as the nave of pharynx, larynx, vagina, bladder,
Speaker 1: and anus. Humans have an unusual relationship with leeches that's
Speaker 1: perhaps unique among all the world's parasites. The use of
Speaker 1: leeches is pervasive throughout the history of medicine, even giving
Speaker 1: the European medical leech harudo medicine alis its modern name.
Speaker 1: In some historical periods, they were so commonly used as
Speaker 1: instruments of blood letting that collecting wild leeches was a
Speaker 1: solid money making operation. Rural leech gatherers would wage bare
Speaker 1: legged through the scum of stagnant ponds, hoping when they
Speaker 1: emerged on the other side to see patterns of glistening
Speaker 1: green black anelids sucking from their ankles and calves. In
Speaker 1: his eighteen oh seven poem Resolution and Independence, the English
Speaker 1: romantic poet William Wordsworth writes about his encounter with this
Speaker 1: brand of leech harvester quote. He told that to these
Speaker 1: waters he had come to gather leeches, being old and poor,
Speaker 1: employment hazardous and wearisome, and he had many hardships to endure.
Speaker 1: From pond to pond, he roamed from more to more,
Speaker 1: housing with God's good help by choice or chance, And
Speaker 1: in this way he gained an honest maintenance. Assuming you
Speaker 1: find the idea of being sucked by a leech somewhat disgusting,
Speaker 1: and assuming you find the idea of being sucked by
Speaker 1: a leech on the inside of your body even more disgusting,
Speaker 1: you might find it odd that the human taste for
Speaker 1: therapeutic parasitism doesn't stop at the outer skin. During the
Speaker 1: leech craze, leaching enthusiasts open many of their bodily orifices
Speaker 1: and internal cavities to the prized worms with the help
Speaker 1: of some ingenious medical technology. In a two thousand eleven
Speaker 1: article on the technological history of leeching, Robert G. W.
Speaker 1: Kirk and Neil Pemberton right that quote. The opening of
Speaker 1: the interior of the body often required the physical alteration
Speaker 1: of the leech, for example, the attachment of thread to
Speaker 1: prevent the loss of the leech within, or the supplementation
Speaker 1: of the leech with mechanical tools to enable the passage
Speaker 1: of the creature into locations such as the anus, where
Speaker 1: it was now recommended as a means to treat problematic prostates.
Speaker 1: There are even a few limited ways in which leeches
Speaker 1: have proven useful, though perhaps still controversial, in the science
Speaker 1: based medicine of recent decades, such as to ensure veins
Speaker 1: are working properly and aren't overfilled or distending after microsurgery.
Speaker 1: Here and there, you can still encounter reports in medical
Speaker 1: journals of rare cases of accidental internal hyerdoniasis, including leeches
Speaker 1: in the throat. In two thousand two, a group of
Speaker 1: doctors reported in the journal Pediatric Pulmonology the case of
Speaker 1: a six year old boy in Syria who was brought
Speaker 1: to the emergency room because he couldn't breathe. His mother
Speaker 1: reported that he had been coughing up blood and that
Speaker 1: a month ago a village doctor had diagnosed the boy
Speaker 1: with asthma and prescribed court steroids and broncho dilators. This
Speaker 1: turned out to be a misdiagnosis. The doctors were able
Speaker 1: to remove a seven centimeter or nearly three inch leach
Speaker 1: from the boy's airway through surgery, and subsequently discovered that
Speaker 1: the child had been drinking from a leech infested stream
Speaker 1: in rural northern Syria. After the leech was removed, the
Speaker 1: boy's symptoms disappeared. In two thousand nine, another group reported
Speaker 1: in the European Journal of Pediatrics the case of an
Speaker 1: eleven year old boy in central Iran who presented it
Speaker 1: a rural healthcare center with blood in his mouth and
Speaker 1: a sore throat that had lasted for two weeks. The
Speaker 1: boy had been given antibiotics for his sore throat and
Speaker 1: the problem did not respond. Inspection of his mouth revealed
Speaker 1: a black circular blob about two centimeters by three centimeters
Speaker 1: or about point eight by one point two inches, stuck
Speaker 1: to the back of his throat, with blood oozing all
Speaker 1: around it. Doctors applied litacaine spray, a topical pain killer,
Speaker 1: and then pull the leech out with blunt forceps. Questioning
Speaker 1: revealed the boy had been swimming in a lake near
Speaker 1: his village. After the leech was removed, blood continued to
Speaker 1: ooze out of the wound for about an hour, but
Speaker 1: otherwise the boy was all right. In a doctor named
Speaker 1: Demeckey McConnon published an article in the Ethiopian Journal of
Speaker 1: Health Science relaying the case of a seven year old
Speaker 1: boy in Ethiopia who presented with blood stained saliva and
Speaker 1: shortness of breath at his home. Someone had tried to
Speaker 1: treat him with a traditional medicine made of tobacco leaves
Speaker 1: and flax seed to no effect. In the report, McConnon
Speaker 1: indicates that the boy had contact with an unprotected source
Speaker 1: of spring water that was also used for watering animals.
Speaker 1: Luring scopy showed some kind of foreign body at the
Speaker 1: top of the trachea. The child was put under general
Speaker 1: anesthesia and the leech was removed with forceps. After the extraction,
Speaker 1: the boy seemed to have a full recovery. Laryngeal and
Speaker 1: pharyngeal leech infestations are rare these days, especially in developed
Speaker 1: countries with access to clean water, but it can still happen.
Speaker 1: Possible symptoms of a leech in the throat are difficulty swallowing,
Speaker 1: sore throat, vomiting blood, coughing up blood, a sense of
Speaker 1: having a foreign body in the throat melna meaning dark
Speaker 1: sticky feces indicating the swallowing of blood, a feeling of
Speaker 1: suffocation or shortness of breath, and harsh or raspy breathing.
Speaker 1: If you think you've got a leech in your throat
Speaker 1: right now, don't panic. Just see a doctor as soon
Speaker 1: as you can, as you may have gathered from the
Speaker 1: cases we just mentioned, pharyngeal or even laryngeal harrod niasis
Speaker 1: is not necessarily a death sentence, though it can be
Speaker 1: dangerous if the parasite obstructs any part of the airway.
Speaker 1: If the doctor knows what to look for and has
Speaker 1: a pair of blunt forceteps on hand, chances are good
Speaker 1: that you'll be all right. But of course the best
Speaker 1: case scenario is to avoid the problem entirely, So don't
Speaker 1: drink dirty water and don't swim in the water where
Speaker 1: the leeches slim. That's our show for this week. Thank
Speaker 1: you so much for tuning in. Further thanks to our
Speaker 1: audio producer Dylan Fagin and our editorial liaison Alison Laddermilk.
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