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Levamisole may reverse a centuries old curse

In January of 2017 CBS Evening News (Lee Cowan) reviewed a book by Doug Preston…The Lost City of the Monkey God.  I won’t spoil the story for you--it’s a must read if you are obsessed with parasitic protozoa as we are.

The Lost City is a captivating true story and reveals a curse bestowed on man.  Legend has it that this ancient and magnificent Lost City, located in the rain-forested mountains of Mosquita was cursed.  Mosquita is a 20,000 square mile section of Honduras and Nicaragua.  The inhabitants lived in the area between 2600 B.C. and 1800 B.C and somehow incurred the ire of the Gods.  The angry Gods brought on a series of catastrophes.  Diseased and devastated, defeated inhabitants melted into the jungle, leaving everything behind, perhaps to appease the Gods.  The Lost City was not Mayan, yet it existed at the same time as the Mayans. These prosperous civilizations vanished at the apex of their existence.

Since the Lost City was first reported by Cortés in 1526, explorers and charlatans searched for them in vain.  That is, until the invention of LIDR in 2010.  The modern three-dimensional radar technology enabled mapping of the ruins beneath the dense canopy. It wasn’t the ruins that revealed the curse--the explorers may be cursed.

If you ask bestselling author Doug Preston, he’ll say he doesn’t believe in curses. And yet, here he is, being treated for leishmaniasis that he contracted while on expedition to The City. Half of the expedition party have contracted leishmaniasis--I believe at least one member died and some are not able to get treatment. The parasite is transmitted by a sand fly, the bite releases the protozoa into the skin and causes lesions that may take years to heal--cutaneous leishmania. Effective treatment at this stage may be life-saving but there are no current satisfactory treatments for cutaneous leishmaniasis.

As disease progresses, the parasite migrates to the mucous membranes of the mouth and the nose, and eats them away; this is mucosal leishmaniasis. The nose falls off, the lips fall off, and eventually the face becomes a gigantic open sore.  Organisms move on to the the organs, and visceral leishmaniasis is often fatal. Visceral leishmania is the second leading cause of parasitic death worldwide. The treatment is rough because it poisons the patients organs.  Patients die from treatment complications of renal or liver failure. Dogs get leishmania and are often euthanized when the diagnosis is made. Horses get leishmania, two cases were reported in Florida. When you read the book, you will realize why the curse reached Western Civilizations. We lead lives that prevent us developing immunity to this developing 20th century threat.

We are invigorated because there are some novel studies to report, and they parallel our investigations.  A promising combination therapy showed a complete clinical cure in 75% of the patients (human) with cutaneous leishmaniasis! The study also reported that 10% of the patients had a partial improvement and alas, the remaining 15% had an underlying chronic diseases and they had no response to the treatment. There were no cytotoxic effects associated with the drugs in the range of the experiments.  The mechanism of action of the drugs predicted promotion of some cytokine gene expression levels and reduced others.  The experiments supported the anticipated changes in cytokines. This is great news because researchers are understanding how to target parasitic protozoal diseases by modulating the response to infection. This has been our mantra for years.

What gives us satisfaction is revealing that the patients were unresponsive to the anti-leishmania drug, Glucantime, but responded when when Glucantime was combined with the immune modulating drug levamisole. Here is some evidence that end-stage unresponsive parasitic protozoal disease in patients is treatable when combined with levamisole.  The absence of cytotoxicity in the treated patients when given the combination of drug/levamisole is also highly noteworthy.

In the last 100 pages of The Lost City, Doug Preston suggests the Curse may be the downfall of Western Civilization--a result of invading parties driving civilizations to extinction by not so unintended consequences and bringing back malady-in-kind.  While we doubt the impact of our studies with levamisole (in horses with EPM and polyneuritis equi) will save the world, we think our efforts are worthy. Support us in our research.  You never know where it will lead.

leishmanialeishmania 2

Leishmania parasites are shown in a host cell and in tissues.

Photos were taken from