Monday, February 6, 2012

Leeches and their Playmates

Sometime before May of 2011, one-time Playboy Playmate Yvette Vickers passed away. Her mummified body was found at her home in Benedict Canyon, CA. Vickers was well known as the female lead in the Gene (not Roger, his brother) Corman cult classic Attack of the Giant Leeches.

Playboy Playmate Pamela Anderson has had her own experience with leeches, as she described to Colin Ferguson in 2008, blaming them for a series of scars on her left shoulder, but admitting that she's lied about it her whole life and she forgets.

A Different Pink "Ribbon" Campaign

Healing Breast Cancer With Leeches?

Malaysian news reports that a Sumatran homeopath claims to have cured breast cancer in many women with the application of leeches.

A bit lacking in the scientific method I am afraid. "I have not kept a record of the numbers but I think I have treated hundreds of women over the years and most of them were cured," Ismail said.

While I am highly skeptical, there is a kernel of truth. Most leeches have an antistasin in their saliva. It is one of many anticoagulants. This particular protein acts by preventing factor Xa from converting prothrombin to thrombin (thus preventing thrombin from converting fibrinogen to fibrin, and so preventing clot formation). Turns out that almost all Xa inhibitors, even those from hookworms have anti-tumor-metastisis functionality because they prevent a new tumor from creating its new blood supply (angiogenesis).
There's even a published research paper demonstrating effectiveness against lung cancer metastasis.

Saturday, July 16, 2011

Nasty MDR Aeromonas from a leech bite. It was only a matter of time.

A 56 yr old man who had leeches applied following facial reconstructive surgery picked up from leeches that were applied an Aeromonas infection that proved to be multi-drug resistant. Ampicillin was used as the initial prophylaxis and later even cipro couldn’t beat the nasty bug back. The flap tissue graft went fully necrotic and failed requiring repeat of the surgery 8 months later.

Given the severity of the outcome for this patient, it is unfortunate that the report, no doubt, continues the insufferable errors regarding the identity of the leech and the diagnosis of the bacterium. The leeches came from a leech supplier. It's already been shown that the leeches universally supplied by commercial outfits are Hirudo verbana, not Hirudo medicinalis. And it's also recently been clear that while the resident crop bacteria in Hirudo medicinalis, is in fact Aeromonas hydrophila, those in in Hirudo verbana most certainly are not; they are Aeromonas veronii.

The implications of these taxonomic identity errors are not trivial. Anyone looking for MDR Aeromonas hydrophila and not finding it in the natural environment could end up scratching their heads – because they’re looking at the wrong bug – the causative agent in this nosocomial leech case was assuredly Aeromonas veronii.

Widespread global use of fluoroquinolones means these antibiotics have been put out there in natural water areas just through flushing. Aeromonas species in leeches are also found living freely in those habitats where they are being exposed to dribbling, but selection-effective quantities of the antibiotics. Since every commercial leech operation needs to replenish its supply of Hirudo verbana from Turkey (as implied in the report), they are all going to bring this nasty bug with them.

Wednesday, April 13, 2011

Sims Medieval

The Sims Medieval now released for the gaming community by EA. Build kingdoms, create heroes, wizards and blacksmiths, battle a witch or... collect leeches if your Sim is a physician! You can look in the ocean and the river for green spots with bubbles and collect them yourself, or buy them from the village store.
I'll ignore, for now, that leeching was more of a post-Enlightenment phenom than it ever was a medieval one.

Friday, December 3, 2010

Biotherapy

Mixed messages from science reporting on a whole bunch of news webpages that just blithely copy each other.
E.g.,
"A new study, which will feature in the International Conference on Biotherapy being held in Los Angeles, has established that using maggots, leeches, and intestinal worms as an alternative to the pills may cure infections and allergies."
"science is beginning to back up their anecdotal claims that maggots, leeches and intestinal worms may be effective in the fight against everything from irritable bowel disease to allergies and psoriasis"
"the use of leeches, maggots and parasitic worms can help cure everything from irritable bowel syndrome to common allergies"

Yes, yes... using percutaneous migrating nematodes might alleviate allergies and asthma.
Yes, yes... maggots do help debrade and disinfect skin wounds.

HOWEVER... while leeches have been approved as a medical device by the FDA, it's got nothing to do with infection, allergy, IBS, or psoriasis. Their use is purely mechanical removal of congested blood in tissue that need time for the restoration of venous circulation. End of story. Nothing magic.

Yeeesh.

Monday, November 1, 2010

Leeches and the Opera

There's been quite a lull in the availability of leeches in the news in recent months, but they have once again reared their awesome anecdotal heads in the story of famed blind tenor Andrea Bocelli.


I had the honor of an impromptu visit from Bocelli a few years back. He was in New York performing and was brought by my office in the course of a behind the scenes tour. Funny, though I knew of his work and stunning range of voice, it had escaped me that he is blind. Regardless, while his companion showed a keen interest in our wormy jars of live bloodsuckers, Mr. Bocelli expressed a revulsion (however mild) that I thought was a bit odd.


Now I get it.


A recent news article reveals that doctors tried to treat Bocelli's congenital blindness with leeches when he was about 12 years old. To no avail of course.


All is explained.

Thursday, April 15, 2010

T. rex found alive, feeding on children in remote Amazonia!


A new genus and species of leech, Tyrranobdella rex Phillips et al. 2010 with enormous teeth was described in the journal PloS ONE on Wednesday of this week. Found feeding from the nose of a 9 yr old child in the upper Amazon by Renzo Arouco-Brown of the School of Medicine at the Universidad Peruana Cayetano Heredia, this new T. rex is known from 3 nasopharyngeal cases, and may well be the first leech species for which Homo sapiens is the type-host.

Phylogenetic work in the publication demonstrates that T. rex is part of a larger evolutionary group of mammal-specific endoparasites, the Praobdellidae, which includes the terrible ferocious leech (Dinobdella ferox) from Asia as well as African and Mexican pests. Mucosal leech infestations by members of this family typically involve the naries, pharynx and hypopharynx, though more alarming mucosal infestation sites are noted by Anna Phillips of the American Museum of Natural History and her co-authors. While leeches are not typically thought to be significant parasites of humans, praobdellid leeches like T. rex have been known to cause life-threatening conditions that range from choking to severe anemia and even death.

In addition to Phillips and Arauco-Brown, authors of this new and formidable T. rex include Mark Siddall and Alejandro Oceguera-Figueroa, also of the American Museum of Natural History, Gloria P.Gomez of the Department of Microbiology at the Universidad Peruana Cayetano Heredia in Lima, María Beltrán of the Enteroparasitology Laboratory at the Peruvian Public Health Center, and Lai Y-Te of the National Taiwan University in Taipei. The research was funded by the the National Science Foundation (DEB-0640463), the Stavros Niarchos fund for Expeditionary Research, a
Theodore Roosevelt Memorial Grant, and a CUNY Science Fellowship.

Monday, January 25, 2010

Branchellion torpedinis - parasite of the day.

In honor of the International Year of Biodiversity, my good friend and colleague Susan Perkins established a blog that designates a quaint quotidian critter as Parasite of the Day, for each and every day of 2010.

Today's entry is the enigmatic elasmobranch ectoparasite, Branchellion torpedinis (submitted by Al Dove of the Georgia Aquarium).

By way of adding to his contribution, please find below here two additional pics of the beautiful frilly leech:


Monday, January 11, 2010

Industrial Leech Husbandry


A recent video piece from Reuters showcases the "International Leech Center" in Udelnaya, outside of Moscow. Alas, and uncritically, the piece gives voice to the local belief (and one that prevailed in European medicine the 1800s) that leeches are a cure-all. Among other things, we are told that they "boost the body's immune system" and "the level of endorphins". I can't find any scientific evidence of (or even studies on) the latter. And while it is true that leeches can induce an immune response, it typically is not a pleasant one. My own exposure to North American medicinal leeches induces what appears to be a delayed-type immune response leading to massive swelling in the afflicted extremity, peaking about 72 hrs after the bite.

Leeches for Learning

Anna Phillips (my student working on medicinal leech diversity) continues her considerable efforts at educating the youth of this nation on the beauty of leeches. The Mount Airy News covered her visit to J.J. Jones Intermediate School in Anna's own home town. Locally she has been involved in the after school programs here at AMNH and she also teaches as a substitute in the science program at the Spence School.

Friday, December 18, 2009

Putting leeches on a tight leash


Holly Tucker of Vanderbilt University writesa nice piece on our fine friends in the most recent New Scientist magazine. Check it out!

Wednesday, October 21, 2009

Forensic Leech Solves Oz Case


Eight years ago Peter Cannon tied up a 71 year old woman in her remote Tasmanian home and stole several hundred dollars in cash. Unbeknownst to Cannon, a terrestrial leech (probably Philaemon grandis, endemic to the island) that had finished feeding on him, dropped off while he was in the midst of theiving.

The case remained unsolved until forensic experts extracted DNA from the leech gut contents, and matched fingerprinting profiles to those on record for Cannon. Cannon promptly plead guilty when faced with the incriminating match.

Wednesday, October 14, 2009

New Leech Species from Jersey


Bill and Carol Ott found a huge leech in a ditch in their backyard in Alloway New Jersey, brought it inside and cared for it. That's a story enough in itself!! "We're just curious people," Carol Ott said.

Beth Wirchansky, a student of Dan Shain's at Rutgers, figured out it was a species new to science, and described it as Haemopis ottorum. Through molecular phylogenetic methods, Wirchansky and Shain corroborated its uniqueness and that its closest relative is Haemopis terrestris.

For the rest of the month, there is a display devoted to Haemopis ottorum, including live specimens, in the lobby of Rutgers-Camden's Science Building!

Congrats Beth.

Wednesday, October 7, 2009

Leeches in Creation Mythology

Last year I posted the Osage Creation Myth in which Macrobdella decora is prominent.

Remarkably, leeches appear in a wide variety of creation myths.

In the Qu'ran:
“then of that fluid-drop (nutfa) We created a leech-like clot" (Quran 23:14)
"then did he become a leech-like clot; then did (Allah) make and fashion (him) in due proportion. And of him He made two sexes, male and female.”(Quran 75: 37-39).

In the creation myth of the Bengali Munda people in India, the benevolent Sun god Sing-Bonga is married to the Moon and brings forth a tortoise, a crab and a leech to create the land by bringing up soil from the sea bed. – Dalton (1872: Descriptive ethnology of Bengal, p 197). "SingBonga ordered them to bring a lump of clay (hasa) from the depth of ocean. The tortoise and the crab failed to do it. The leech went deep and deep to the ocean and finally found bit clay from the depths of the ocean and gifted it to the Supreme Sing Bonga. SingBonga by his power transformed the bit of clay into the earth. "

In Shinto creation mythology "After the sun and moon, the next child Izanagi no Mikoto and Izanami no Mikoto gave birth to was the leech-child. When this child had completed his third year, he was nevertheless still unable to stand upright." Alternatively: "The child which was born to them was Hiruko (the leech-child), which when three years old was still unable to stand upright. So they placed the leech-child in a boat of reeds and let it float away."

Tuesday, September 15, 2009

Friday, August 21, 2009

The Great Leech Of Tlanusi'yï

I recently had the opportunity to attempt a face-to-face encounter with the largest and most feared leech of North America.

As described by James Mooney (1891), in his accounts of the Cherokee myths and sacred formulas...

"The spot where Valley river joins Hiwassee, at Murphy, in North Carolina, is known among the Cherokees as Tlanusi'yï, 'The Leech place,' and this is the story they tell of it:

"Just above the junction is a deep hole in Valley river, and above it is a ledge of rock running across the stream, over which people used to go as on a bridge. On the south side the trail ascended a high bank, from which they could look down into the water. One day some men going along the trail saw a great red object, full as large as a house, lying on the rock ledge in the middle of the stream below them. As they stood wondering what it could be they saw it unroll--and then they knew it was alive--and stretch itself out along the rock until it looked like a great leech with red and white stripes along its body. It rolled up into a ball and again stretched out at full length, and at last crawled down the rock and was out of sight in the deep water. The water began to boil and foam, and a great column of white spray was thrown high in the air and came down like a waterspout upon the very spot where the men had been standing,. and would have swept them all into the water but that they saw it in time and ran from the place.

"More than one person was carried down in this way, and their friends would find the body afterwards lying upon the bank with the ears and nose eaten off, until at last the people were afraid to go across the ledge any more, on account of the great leech, or even to go along that part of the trail. But there was one young fellow who laughed at the whole story, and said that he was not afraid of anything in Valley river, as he would show them. So one day he painted his face and put on his finest buckskin and started off toward the river, while all the people followed at a distance to see what might happen. Down the trail he went and out upon the ledge of rock, singing in high spirits:


Tlanu'si gäe'ga digi'gäge
Dakwa'nitlaste'stï.
I'll tie red leech skins
On my legs for garters.


"But before he was half way across the water began to boil into white foam and a great wave rose and swept over the rock and carried him down, and he was never seen again.

"Just before the Removal, sixty years ago, two women went out upon the ledge to fish. Their friends warned them of the danger, but one woman who had her baby on her back said, 'There are fish there and I'm going to have some; I'm tired of this fat meat.' She laid the child down on the rock and was preparing the line when the water suddenly rose and swept over the ledge, and would have carried off the child but that the mother ran in time to save it. The great leech is still there in the deep hole, because when people look down they see something alive moving about on the bottom, and although they can not distinguish its shape on account of the ripples on the water, yet they know it is the leech. Some say there is an underground waterway across to Nottely river, not far above the mouth, where the river bends over toward Murphy, and sometimes the leech goes over there and makes the water boil as it used to at the rock ledge. They call this spot on Nottely 'The Leech place' also.

Tuesday, July 28, 2009

Leech Invasion in Atsugi Japan!!!!

I love the dramatic music.

The Eyes Have it!!!

As an undergraduate student taking Sherwin Desser's JZM252 parasitology course, I was fascinated by the nummber of "worm-in-the-eye" stories with which he regaled us. Loa loa, Onchocerca, Alaria, bot fly larvae, Toxocara (like Baylisascaris procyonis featured in an episode of House)... all potential eye parasites... ugh.
     I have often shown the image at right in public presentations about leeches. If you look closely you can see a Dinobdella ferox peeking out from behind someone's lower upper eyelid and it's back sucker holding onto the eyeball itself (the eye is upside down). This was sent to Gene Burreson by a physician in India many years ago, and it never fails to first confuse, and then disgust, a lunch-time scientific audience!
     The tribulations of people with leeches in their eyes continues. In regions of the world where the terrestrial leeches abound, like Australia and in the wet forests of Madagascar, leeches in the eyes and ears is all too common. Getting aquatic leeches in an eye, while less common, is perhaps more terrifying in light of the larger size of these "medicinal" leeches.
     The Australian story is remarkable for this misperception: "Dr Fogg says tweezers were not an option as simply pulling the leech off could leave its head lodged in the eyeball, leading to infection." Even if leeches had a head, which they do not, for this to be true, the head would have to embed, which it does not since the leech would be unable to suck blood without the seal it makes with its oral sucker.
     We might have Hollywood to blame for this. In The African Queen, Humphry Bogart's character Allnut (a Canadian, I might add), when he emerges from a swamp covered in leeches, declares to Rose (Katharine Hepburn), "No, no, don't touch 'em, don't! Salt, Rosie! ... You pull 'em off but their heads stay in! Poison the blood! Get the salt... If there's anything in the world I hate, it's leeches. Oooh, the filthy little devils."
     If you do get a leech in your eye, salt water will get it out. It will have to be saltier than your tears, so it's likely to sting, and you'll want to flush your eyeball with water afterwards.
     Every photograph of a leech in an eye is one where someone ran for a camera first instead of getting the thing out!

Thursday, July 23, 2009

Marshal Brain - HowStuff(doesn't)Works

Marshall Brain, creator of HowStuffWorks (now a subsidiary of Discovery), which purports to be a clearing house of accurate technological information, badly mangles the truth about leeches in two podcasts: one on what is a medical [sic] leech and the other on how to remove a leech. In these uncited, apparently non-fact-checked articles (none of the leech biologists I know got a call), beyond the preposterous assertion that leeches look like slugs, Mr. Brain claims:
1) that leeches merely double in size when they feed (they can increase 5 times their weight or more).
2) that leeches raised in captivity are "sterile to a certain degree" (all leeches, wild or farm raised harbour Aeromonas in their crop; a course of antibiotics is recommended during post-operative leech therapy)
3) that they quickly attach and start feeding (far from true, especially in North America)
4) that leeches hold on with rows of tiny teeth (they hold on with their suckers, the teeth, far too small for holding onto anything, and which do not meet in any kind of bite, are used only for making incisions)
5) that removal of leeches requires one "to rip the teeth away from your skin" (in fact all that is needed is to gently break the suction seal made by the oral sucker at the smaller end of the leech, once that seal is broken, the leech cannot hold on and can be readily removed by detaching the posterior sucker)
6) that is will not hurt "because the leech has injected a numbing agent" (see my previous post about this unsubstantiated myth)

This is all timely in light of Carl Zimmer taking to task George Will and the Washington Post for failure to fact check on science. Alas, some science writers too fail to fact check. Please note that Discover Magazine where Carl is a columnist has no relationship with Discovery Communications where Brain blogs about "stuff", like medical medicinal leeches.