
Take Two Leeches and Call Me in the Morning
Season 5 Episode 6 | 3m 11sVideo has Closed Captions
Once used for questionable treatments, leeches now help doctors to reattach body parts.
The same blood-sucking leeches feared by hikers and swimmers are making a comeback... in hospitals. Once used for questionable treatments, leeches now help doctors complete complex surgeries to reattach severed body parts.
Problems with Closed Captions? Closed Captioning Feedback
Problems with Closed Captions? Closed Captioning Feedback

Take Two Leeches and Call Me in the Morning
Season 5 Episode 6 | 3m 11sVideo has Closed Captions
The same blood-sucking leeches feared by hikers and swimmers are making a comeback... in hospitals. Once used for questionable treatments, leeches now help doctors complete complex surgeries to reattach severed body parts.
Problems with Closed Captions? Closed Captioning Feedback
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Learn Moreabout PBS online sponsorshipHey folks - this episode is bit more *bloody * than usual.
Especially a little after the two-minute mark.
Just letting you know in case flesh wounds aren't your thing.
Thanks for watching.
Ah... the leech.
Ravenous blood-sucker.
Parasite.
Nemesis to hikers.
But it wasn't always this way.
The same leech that's dreaded by pond-swimmers, was once a hot commodity.
For thousands of years, draining blood from patients was considered one of the best treatments for everything from smallpox to scurvy.
And healers often used leeches to suck that blood out.
Their favorite was Hirudo medicinalis.
But losing all that blood usually did more harm than good, further weakening patients.
By the end of the 18th century, science-based medicine was in, and leeches were out... at least for a while....
So what are leeches anyway?
Just horrible little vampires?
Well, actually they're more like earthworms, in fact they share a common ancestor.
But some leeches developed a taste for blood.
And they've become experts at stealing it.
Leeches have suckers on both ends of their body.
They use them to inchworm around.
The big sucker at the back anchors the leech.
Inside that front sucker is a muscular jaw bearing three razor-sharp teeth.
They use them to saw through the skin.
Once suctioned into place, the leech spews chemicals into the wound.
Like anticoagulants that thin the blood, keeping it from clotting.
That lets the leech slowly suck away for up to 40 minutes.
When done, it leaves a three-point scar.
At hospitals like California Pacific Medical Center in San Francisco, leeches have made a comeback.
OK, get ready...
When doctors reattach body parts like fingers and ears, blood sometimes pools in them, keeping fresh blood from getting in.
That's where our buddy the leech comes in.
Sucking out the stale blood to make way for the good stuff.
Doctors literally prescribe leeches to help a patient recover.
The medicine has changed, but the tool?
It's the same.
The leech.
Continuing its creepy, though sometimes helpful relationship with us.
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