The medical symbol known as the staff of Asclepius consists of a staff with a serpent coiled around it (Fig. 1).

The worship of Asclepius as the god of medicine began in ancient Greece and spread throughout Europe.  He is believed to have been a famous doctor from Thessaly in Greece who actually existed at some time in the twelfth century B.C., later being deified in Greek mythology. According to legend, Asclepius was the son of the god Apollo and a young mortal named Coronis, the daughter of Phlegyas, the king of Thessaly.

Apollo was the god of medicine, music and the arts, having also other attributes as oracle of Delphis to keep him busy.  After becoming pregnant with Apollo’s child, Coronis fell in love with a young man called Ischys.  A white crow informed Apollo of the love affair which made the god so angry that he changed the color of the bird to black and decided to seek vengeance through his sister Artemis, by convincing her to shoot Coronis with a poisoned arrow.  When Coronis’ body was on the funeral pyre, ready for cremation, Apollo remembered she was carrying his offspring and removed the child by means of a caesarean section handing it over to Chiron, a centaur, to be brought up.

In Greek mythology the centaurs were hybrid beings, half men half horses that lived in the mountains of Thessaly.  Chiron, unlike other centaurs, as well as being endowed with great strength was also kind and wise, and had cared for other Greek mythological figures such as Jason, hero of the Argonauts, Heracles (Hercules) and also Achilles, the Trojan War hero.

Asclepius inherited his father’s vocation for healing and learned from Chiron how to handle medicinal plants.  He became a famous doctor, eventually married and had the following children: Podalirius, Macaon, Hygeia, Panacea, Aegle, Acesius and Iaso. Podalirius and Macaon took part in the war against Troy and are mentioned by Homer in the Iliad.  Hygeia and Panacea who worked with their father are well known names in the medical field: Hygiene in the prevention of diseases and panacea as the cure for all illnesses.  Unfortunately, Asclepius overstepped the limits of medicine by bringing the dead back to life for which he was punished by Zeus who struck him dead with a thunderbolt.    Apollo begged Zeus to deify Asclepius who then became the god of medicine. The worship of Asclepius spread across Greece and throughout the Roman Empire and other regions. Temples called Asclepions were built where the sick were treated by the Asclepiades, who were half priest and half doctor and applied rational therapeutic methods together with religious practices (Hart, 2000).

Archaeological findings from the temples of Asclepius, such as statues and ancient coins all show the god holding the staff with the serpent.  The meaning of each of these elements has given rise to controversy.  Three interpretations of the staff have been considered plausible: the representation of the tree of life, the symbol of authority and power (to cure) and last but not least support and defense for walking since doctors then were itinerant and traveled long distances on foot. In regard to the serpent there is an easier explanation as this animal has always fascinated different peoples and civilizations in connection with the power to preserve life.  The ability to form a circle with its own body is seen as a symbol of eternity and its periodic change of skin as a sign of rejuvenation.  Since it is a chtonic being capable of living both on the surface and underground it is supposed to have access to both the visible and invisible worlds.  It is also associated with cunning, caution and wisdom.  The serpent is often seen with other gods such as Athens, Hera, Demeter and Hermes (and their Roman equivalents).

The worship of Asclepius was at its height around the third century A.D. when Christian domination banned the pagan gods, causing the staff of Asclepius to practically disappear until the sixteenth century when it resurfaced as the universal symbol of medicine.   The symbol of Hermes called the caduceus with two serpents and wings at the top, has been mistakenly used in the USA as the symbol of medicine when it is, in fact, the symbol of commerce.  In recent years, more precisely during the last decade, an odd interpretation of the symbol of medicine appeared, more in line with popular culture, associating it to the parasitosis caused by the Dracunculus medinensis nematode, popularly known as guinea worm, medina worm or serpent worm.  

This nematode has a complex biological cycle. The larvae, in an aquatic environment, infect a microscopic crustacean of the copepod class.  The animal host, man included, is infected by drinking water contaminated by the infected crustaceans.  Once in the stomach, the crustaceans die freeing the larvae that are resistant to the gastric juices.  The larvae go through the intestinal wall entering the abdominal cavity and lymphatic system.  Over the next six weeks they move toward the subcutaneous tissue.  One year later the larvae have reached adulthood.  The males, more slender than the females, die while these survive in the subcutaneous tissue as elongated worms, moving slowing, preferably, in the direction of the lower members.  After some time the worm produces a skin ulcer through which it extrudes its proximal end.  As the ulcer is very painful the patient tends to bathe it looking for relief.  This is when the worm expels larvae through its mouth contaminating the water that will, in turn infect new crustaceans, closing the biological cycle. An abscess is formed in the site after the death of the worm.  Extraction of the living worm is possible before ulceration by the following process: An incision is made in the skin just ahead of the worm which will soon surface.  A small rod, such as a matchstick is then used to carefully and progressively coil the worm. The rod must be turned gently over a period of days until the worm is completely removed (fig. 2).

Dracunculiasis has existed since times immemorial, having been detected in Egyptian mummies.  The therapeutic procedure described above is traditional and its source is not known.  Lately the stick with the nematode coiled around it has been considered the origin of the staff of Asclepius.  The medical symbol would then be reduced to serving as nothing more than publicity on the part of the doctor, informing his ability to extract subcutaneous parasites.  This imaginative interpretation, as mentioned above, is recent.  The Internet is flooded with articles on the subject published over the last decade, some of them repeating what others have already mentioned.  The oldest record found is from 2002 and refers to an article published by Doctor Keith Thomas Blayney from New Zealand.  This article entitled "The Caduceus vs. the Staff of Asclepius" was published on-line at the site http://drblayney.com/Asclepius.ht having undergone a revision in 2005. There is no bibliography in the article and Blanley only suggests that the probable origin of the symbol of medicine is the procedure for treatment of dracunculiasis.  Blainey published his theory in the Alternative Journal of Nursing July 2007, Issue 14, page 4. And he is cited as the bibliographic source in Wikipedia and other publications broadcasted by the Internet.

 30 sites mentioning the same story have been revised, most of them without bibliographic references using expressions such as “some scholars believe”, “it is accepted that”, “it is assumed” and so on.  Of the thirty sites, 17 show the publication date, six being from 2011, indicating current interest in the subject.

Is Dr. Blayney the creator of this absurd interpretation of the origin of the symbol of medicine or has some historian before him suggested this idea? What documentation is there to prove it? Are we facing a case of pure imagination?

Classical and modern historians such as Dipgen (1932), Laignel-Lavastine (1936), Castiglioni (1947), Major (1954), Sigerist (1961), Garrison (1966), Lain Entralgo (1971) and so many others have never referred to this possibility and neither have authors of  specialized studies on Asclepius and the symbol of medicine. Emma and Ludwig Edelstein made a thorough survey of all the Greco-Roman literature referring to Asclepius.  They found 861 references, none of them so much as hinting that there might be any connection between the staff of Asclepius and the treatment of dracunculiasis.  Other recent works, such as the book Asclepius the God of Medicine, by Gerald Hart, published in 2000 say nothing of this novelty that is being proclaimed as the truth.

Visiting Greece in 1987 and also in 1996 to take part in the 35th International Conference on the History of Medicine held on the island of Kos, I had the opportunity of going on guided tours to the ruins of the temples of Asclepius in Epidaurus and in Kos.  On neither of these occasions was any reference made to this probable origin of the symbol of medicine, the same occurring in the temple of Asclepius in Pergamon in Turkey.  I was recently informed that tourist guides have included this version in their narratives to visitors*.  Something similar may happen to this bizarre explanation as happened to Hermes’ caduceus which has been mistakenly accepted as the symbol of medicine. It is to be feared that in spite of this new interpretation being no more than speculation and not based on historical fact, it may spread and be accepted permanently.  We will then see the staff of Asclepius reduced to a matchstick and the serpent to no more than a helminthic parasite.  

* According to Dr. Luiz Rassi Jr., who has recently been to Greece.


1. Hart, G.D. – Asclepius the God of Medicine. Royal Society of Medicine, 2000.
2. Dipgen, P. - Historia de la Medicina (trad.). Barcelona, 1932
3. Laignel-Lavastine. - Histoire Générale de la Médecine, de la Pharmacie, de l’Art
dentaire e de l’Art vétérinaire. Paris, Albin Michel Ed., 1936.
4. Castiglione, A. – Historia da Medicina (trad.). São Paulo, Cia. Ed. Nacional, 1947
5. Major, R.H. – A History of Medicine. Oxford, Blackwell Scientific Publ., 1954.
6. Sigerist, H.E – A History of Medicine. Oxford University Press, 1961.
7. Garrison, F. – Historia de la Medicina, 4ª. ed. (trad.), México, 1966.
8. Entralgo, L – Historia Universal de la Medicina. Barcelona, Salvat Ed., 1971.
9. Edelstein, E.J., Edelstein, L. – Asclepius. Collection and interpretation of the testimonies. Baltimore, The Johns Hopkins University Press, 1998.

Note: In Portuguese the name Asclépio has been spelled in a number of different ways: Asclépio, Asclépios Asclepius, Asklepio, Asklepios, Asklepiós, Asklepius. I have used the simplest that is also used by the Academia Brasleira de Letras.

Translator’s note: Likewise in English, the name Asclepius can also be spelled Asculapius, Aesculapius (Latin) and Asklepius (Greek).

Joffre Marcondes de Rezende
Prof. Emérito da Fac. de Medicina da Univ. Federal de Goiás