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Medical Index
First Posted: Sept 13, 2010
Sep 13, 2010

Dracunculus Medinensis or Guinea-worm

Sept. 13, 2010, my vet came to give fall shots, do teeth floating and sheath cleaning. We were talking and Dr. French metioned that she learned in vet school that the medical symbol (The Caduceus or Asclepius) was actually not a serpent, but rather a worm, the Dracunculus Medinensis or Geuinea-worm. She also noted that there are a number of theories on this idea. I decided to research and post an article on this. This has been great fun. The parasite is disguesting!

Dracunculus medinensis or Guinea-worm

The best known species is D. medinensis, known commonly as the Guinea worm. This parasite is frequently found in the subcutaneous tissues and muscles of humans, dogs, and sometimes cattle and horses. The medical name for this condition is dracunculiasis. The disease causes cutaneous nodules and subsequent ulcers. The anterior end of the adult female worm protrudes from the host animal's body, most commonly on a lower limb, through an ulcer. When the worm feels the presence of cold water, muscle contractions in its body cause its uterus (which fills the whole body cavity) to burst, releasing hundreds of thousands of first-stage larvae into the water, where they can find new hosts.

D. insignis infects dogs and wild carnivores, causing cutaneous lesions, ulcers, and sometimes heart and vertebral column lesions. Like D. medinensis, it is also known as Guinea worm, as well as Dragon or Fiery Dragon.

DNA fingerprinting can differentiate between D. medinensis and D. insignis, which is important to efforts to eradicate dracunculiasis.

Other Species: D. fuelliborni parasitizes opossum, D. lutrae parasitizes otters, and D. ophidensis parasitizes reptiles.

Life Cycle

Dracunculus Medinensis

The life cycle was elucidated in 1870 when Alexei Pavlovich Fedchenko of Russia discovered the copepod crustacean intermediate host stages.

Rod of Asclepius

Rod of Asclepius

It has been suggested that the symbol once represented a worm wrapped around a rod; parasitic worms such as the guinea worm (Dracunculus medinensis) were common in ancient times, and were extracted from beneath the skin by winding them slowly around a stick. According to this theory, physicians might have advertised this common service by posting a sign depicting a worm on a rod. However plausible, no concrete evidence in support of this theory has been adduced.

"The probable medical origin of the single serpent around a rod: In ancient times infection by parasitic worms was common. The filarial worm Dracunculus medinensis aka "the fiery serpent", aka "the dragon of Medina" aka "the guinea worm" crawled around the victim's body, just under the skin. Physicians treated this infection by cutting a slit in the patient's skin, just in front of the worm's path. As the worm crawled out the cut, the physician carefully wound the pest around a stick until the entire animal had been removed. It is believed that because this type of infection was so common, physicians advertised their services by displaying a sign with the worm on a stick." The Caduceus vs the Staff of Asclepius (Asklepian 03)

The Caduceus of Mercury (Roman) and the Karykeion of Hermes (Greek)

"...The caduceus as a Medical symbol: The link between Hermes and his caduceus and medicine seems to have arisen by Hermes links with alchemy. Alchemists were referred to as the sons of Hermes, as Hermetists or Hermeticists and as "practitioners of the hermetic arts". By the end of the sixteenth century, the study of alchemy included not only medicine and pharmaceuticals but chemistry, mining and metallurgy. Despite learned opinion that it is the single snake staff of Asclepius that is the proper symbol of medicine, many medical groups have adopted the twin serpent caduceus of Hermes or Mercury as a medical symbol during the nineteenth and twentieth centuries.

Like the staff of Asclepius, the caduceus became associated with medicine through its use as a printer's mark, as printers saw themselves as messengers of the printed word and diffusers of knowledge (hence the choice of the symbol of the messenger of the ancient gods). A major reason for the current popularity of the caduceus as a medical symbol was its illinformed official adoption as the insignia for the Medical Department of the United States Army in 1902..."

For an excellent article on the Caduceus follow this link: The Caduceus vs the Staff of Asclepius (Asklepian)

For More Information:

Dracunculus Medinensis
Life Cycle of Dracunculus Medinensis
Differentiating Dracunculus medinensis from D. insignis, by the sequence analysis of the 18S rRNA gene
Dracunculus medinensis
Dracunculiasis (Guinea Worm Disease) Eradication
Dracunculiasis, also called guinea worm disease (GWD

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