According to Wikipedia, "The caduceus is often incorrectly used as a symbol of healthcare organizations and medical practice, particularly in the United States of America, due to confusion with the traditional medical symbol, the Rod of Asclepius, which has only one snake and is never depicted with wings – the logo of the World Health Organization uses the Rod of Asclepius as its basis."
Just so's we're clear: the staff of Hermes, known as the caduceus, has two serpents coiled round it and is the symbol of logistics; the Rod of Asclepius has only one serpent coiled round it, and is the symbol of medicine (and healing).
I am guilty of confusing the two myself, on this page – or I was, until I corrected it.
As every visitor to this website should know, Hermes was the messenger of the Greek gods. His Roman equivalent was Mercury. Asclepius is less well known; the son of Apollo, he was the god of medicine and healing. He had several sons and daughters. His daughters personified various aspects of his domains; the best known of them is probably Hygieia, the goddess of cleanliness.
Hippocrates, the Greek father of medicine, is said to have worshipped at a temple dedicated to Asclepius (known as an asclepion – or, in English, a healing temple).
© Haydn Thompson 2020