The letters around the snake on a medical symbol depend on which organization’s logo you’re looking at. The snake itself, coiled around a staff, is one of the oldest symbols in medicine, rooted in the Greek god of healing, Asclepius. But the letters surrounding it typically represent the name or function of a specific health organization, such as WHO for the World Health Organization, or a “V” for veterinary medicine. In some cases, the surrounding design isn’t letters at all but geometric shapes with their own meaning.
The Snake and Staff at the Center
Nearly every medical logo featuring a snake draws from the same source: the Rod of Asclepius. This is a simple staff with a single serpent coiled around it, named after the Greek god of healing and medicine. The snake was chosen as a symbol of rejuvenation because snakes shed their skin, a process ancient cultures viewed as a form of rebirth.
A common point of confusion is the difference between this symbol and the caduceus, the staff of Hermes, the Greek messenger god. The caduceus has two snakes and a pair of wings at the top. Hermes was a patron of commerce and negotiation, not medicine. Yet for over a century, the caduceus has been mistakenly used in medical contexts, largely because the U.S. Army Medical Corps adopted it as its insignia in 1902. The U.S. Public Health Service and many American publishers followed, cementing the mix-up. When you see two snakes with wings, you’re technically looking at a symbol of trade, not healing.
The WHO Emblem
One of the most widely recognized snake-and-letters logos belongs to the World Health Organization. The WHO emblem places the Rod of Asclepius (single snake, no wings) on top of a globe framed by the United Nations laurel wreath. The letters “WHO” don’t appear inside the emblem itself, but the surrounding design elements represent global health governance under the UN system. If you’ve seen this logo on vaccination cards, health guidelines, or news coverage, the wreath and globe are the “letters” or shapes framing the snake.
The Star of Life in Emergency Medicine
If the snake you’re looking at sits inside a blue, six-pointed star, you’re looking at the Star of Life, the symbol used by emergency medical services. The six bars of the star aren’t letters, but each one represents a step in the emergency care chain: detection, reporting, response, on-scene care, care in transit, and transfer to definitive care. The Rod of Asclepius sits at the center. You’ll find this symbol on ambulances, paramedic uniforms, and emergency room signage throughout the United States and many other countries.
The “V” in Veterinary Medicine
In veterinary medicine, the snake and staff appear with a large letter “V” superimposed over them. The American Veterinary Medical Association uses this design in its logo, with the V simply standing for “veterinary.” The staff underneath is referred to as the Aesculapian staff (an alternate spelling of Asclepius), connecting animal medicine to the same ancient tradition of healing.
The Bowl of Hygeia in Pharmacy
Pharmacy uses a slightly different snake symbol: a serpent wrapped around a bowl or chalice rather than a staff. This is the Bowl of Hygeia, named after Hygeia, the Greek goddess of health and daughter of Asclepius. The cup represents medicine itself, while the snake represents healing. You’ll see this symbol on pharmacy storefronts and prescription bottles, sometimes surrounded by the letters of a national pharmacy association or the abbreviation “Rx.”
Where “Rx” Comes From
Speaking of Rx, this familiar symbol on prescriptions is not directly related to the snake imagery, though the two often appear near each other on pharmacy logos. The most widely accepted origin is that Rx is simply an abbreviation of the Latin word “recipe,” meaning “take.” An alternative theory suggests it comes from the astronomical sign for Jupiter, which was once invoked on prescriptions as a kind of blessing, but there’s no strong evidence for that claim. A more recent proposal links it to the Eye of Horus from ancient Egypt, though that connection remains unproven as well.
Other Professional Letters You Might See
Many medical organizations frame the snake symbol with their own acronym or initials. The letters AMA surround or accompany the symbol for the American Medical Association. Military medical branches display the caduceus (the two-snake version) alongside corps designations. Country-specific medical councils place their national abbreviations around the staff. In each case, the letters simply identify the organization, while the snake carries the symbolic weight of the healing tradition.
So when you see letters around a snake on a medical logo, the snake and staff represent the ancient connection between medicine and renewal. The letters around it tell you which specific institution, profession, or service is claiming that tradition as its own.