0:00:02 > 0:00:04- Are you ready for our Ouch! Snips? - Snip!- Ouch!- Exactly!
0:00:09 > 0:00:12What have these two ugly critters got in common?
0:00:12 > 0:00:16They may not look very pretty, but these guys are both miracle healers.
0:00:16 > 0:00:20First up, this is a leech, and it's a type of worm.
0:00:20 > 0:00:24Whereas we only have one brain, a leech has 32.
0:00:24 > 0:00:31- And while we have 32 teeth, a leech has 125.- Their main diet is blood.
0:00:31 > 0:00:34And, in fact, right now, I'm providing lunch for this one.
0:00:34 > 0:00:35Whilst it's on my arm,
0:00:35 > 0:00:39it's going to eat five times its own body weight in my blood.
0:00:39 > 0:00:42That's the equivalent of me eating a small cow - hooves and horns
0:00:42 > 0:00:45and everything. It's not just greedy - it's disgusting.
0:00:45 > 0:00:48But these wrigglers can actually save human lives -
0:00:48 > 0:00:50all by sucking our blood.
0:00:50 > 0:00:54To get drinking, this leech has bitten me, and now its saliva
0:00:54 > 0:00:57is working its way into my veins, releasing a chemical which
0:00:57 > 0:01:00will thin my blood, preventing it from clotting.
0:01:00 > 0:01:03And it's this ability to get our blood flowing that surgeons
0:01:03 > 0:01:04use in modern medicine.
0:01:06 > 0:01:09So let's say you chop off the end of your finger.
0:01:09 > 0:01:13A surgeon can attach the finger but, if blood clots have formed inside
0:01:13 > 0:01:17the bit of dead finger, new blood can't get in and it will fall off.
0:01:17 > 0:01:21What doctors can now do is attach a leech to the tip of the finger,
0:01:21 > 0:01:23and the same chemicals that allow my blood to
0:01:23 > 0:01:25flow into the leech on my arm dissolve the clots
0:01:25 > 0:01:29and allow fresh blood to enter the reattached finger.
0:01:29 > 0:01:32There's no fancy machine or drug that can do this job
0:01:32 > 0:01:33as successfully as a leech.
0:01:35 > 0:01:38Well, after an hour and a half on my arm, it's finally full,
0:01:38 > 0:01:41and you can see how it's got the blood in my arm flowing.
0:01:41 > 0:01:43This is the point. If you've cut your finger off,
0:01:43 > 0:01:45if the surgeon's reattached the finger,
0:01:45 > 0:01:49it's the chemicals that are now making me bleed that allow
0:01:49 > 0:01:53new blood vessels and new blood to flow into the reattached finger.
0:01:53 > 0:01:56They may be greedy, they may be frankly disgusting,
0:01:56 > 0:01:59but it is that that means they are the most amazing healers.
0:01:59 > 0:02:04And you can see how much it's grown. It really is five times bigger.
0:02:04 > 0:02:07I got quite attached to that! Literally.
0:02:07 > 0:02:09And leeches aren't the only creatures with amazing
0:02:09 > 0:02:13healing abilities. Time to meet our next wriggly doctors.
0:02:13 > 0:02:15These are maggots. Nice!
0:02:15 > 0:02:18Now, you've probably seen maggots before, and these are the same
0:02:18 > 0:02:22scary maggots that you see in dead animals and in horror movies.
0:02:22 > 0:02:25But there's one really important difference -
0:02:25 > 0:02:27these maggots are sterile.
0:02:27 > 0:02:29These are superhero maggots.
0:02:29 > 0:02:31Being completely germfree means
0:02:31 > 0:02:34they can be used in hospitals for a very important job -
0:02:34 > 0:02:37to clean dead skin away from large wounds, allowing them to heal.
0:02:38 > 0:02:40So these are nice maggots.
0:02:42 > 0:02:43Kind of!
0:02:43 > 0:02:47In here, there's a foot with a wound with 500 maggots in it.
0:02:47 > 0:02:50Let's go see them in action. Not if you're squeamish.
0:02:51 > 0:02:54Prepare to look away. But not yet.
0:02:54 > 0:02:55This is Ros Thomas.
0:02:55 > 0:02:59She's a foot doctor, or podiatrist, and she's going to be tackling this.
0:02:59 > 0:03:03It's a foot with a nasty wound on the bottom of it and a sock,
0:03:03 > 0:03:04so it's still all right to look.
0:03:04 > 0:03:06Maggots have been on the wound for two days,
0:03:06 > 0:03:10and now it's time to see what they've done. Get ready, people!
0:03:10 > 0:03:12Hopefully, they've had a good feed now.
0:03:12 > 0:03:14Hopefully, we'll see a nice clean wound.
0:03:15 > 0:03:19Prepare yourself - it can look a bit icky. And there we go.
0:03:19 > 0:03:23- Are you looking?- Cleaned up quite a bit. Not completely.
0:03:23 > 0:03:25And they're still quite lively there.
0:03:25 > 0:03:27They're our little blind,
0:03:27 > 0:03:30legless surgeons that help to clean up all the mucky tissue.
0:03:30 > 0:03:34- So they're very precise surgeons? - They're very precise surgeons, yes.
0:03:34 > 0:03:35Take a closer look.
0:03:35 > 0:03:38Although they can eat dead flesh, maggots don't have any teeth.
0:03:38 > 0:03:41They vomit powerful chemicals onto the wound,
0:03:41 > 0:03:44which dissolves dead flesh, and the maggot can then eat
0:03:44 > 0:03:46that along with any bacteria that are around.
0:03:46 > 0:03:50And that is what makes them perfect wound-cleaning machines.
0:03:50 > 0:03:54It's looking so much better than it was originally cos it was
0:03:54 > 0:03:57completely covered with yellow mucky tissue.
0:03:57 > 0:04:00Yes, it was, but that yellow tissue was all dead flesh.
0:04:00 > 0:04:03So although it might look worse now - are you still looking? -
0:04:03 > 0:04:05in fact, it's much healthier.
0:04:05 > 0:04:09This patient's wound has improved a lot in two days, but don't worry -
0:04:09 > 0:04:12the maggots won't eat the healthy flesh, only the dead stuff.
0:04:12 > 0:04:16No-one's going to be eaten alive. So that's a relief!
0:04:16 > 0:04:19We normally think of maggots as eating rotting things in bins,
0:04:19 > 0:04:22but it's this ability to just eat rotten flesh that makes them
0:04:22 > 0:04:23such good healers.
0:04:23 > 0:04:27Whereas a human surgeon might have to amputate a foot, 500 blind,
0:04:27 > 0:04:30tiny, legless surgeons are able to eat only the dead flesh
0:04:30 > 0:04:32and therefore save the foot.
0:04:32 > 0:04:35It's amazing to think that, even with all the medical research
0:04:35 > 0:04:39and technology available, we still can't beat miracle treatment
0:04:39 > 0:04:42given by two very strange-looking doctors.
0:04:42 > 0:04:44Maybe they aren't so ugly after all.
0:04:44 > 0:04:47- See you next time!- Bye.- Bye.
0:04:47 > 0:04:51- Bye.- Bye.- Bye!- Bye.- Bye!
0:04:51 > 0:04:53NO SOUND