• Thảo Mac

A Brief History of Vaccines: From Legends to Modern Day

Vaccinology, also known as the science of vaccines, seems to be a relatively young field of medical studies — the term was only coined in 1977 by Jonas Salk. However, a closer look at history reveals that humanity’s first attempt to fight infectious disease was recorded far earlier than that.

(Source: About History)

It all started with a crazy idea. According to legends, Mithridates VI — a Roman ruler who reigned the land of Pontus on the Black Sea around 120 to 63 BC, and a proud possessor of terrible paranoia — ingested a toxic concoction of plant oils and resins daily. The idea was to build his toxin tolerance to protect himself against assassination attempts. As incomprehensible as it may have sounded at the time, the idea seemed to have worked. When Pompey defeated Mithridates VI and granted him a death by poison, the Roman general was in for a surprise when the defeated king seemed unable to die. How the Pontus King actually died — and if his elixir worked — is contested, but the concoction became the basis of the universal antidotes Mithridatium and Theriac.

Mithridates VI was not the only notable figure who had the idea of building tolerance by ingesting toxins. The same process was also recorded in China by Buddhist monks, who ingested snake venom to protect themselves against its deadliness. Other legends indicate that the same method was applied in many places of the world to ward off diseases like smallpox and measles, although records are unclear.

But several centuries later, Emperor Kangxi of China used this technique to fight against smallpox in the latter half of the seventeenth century. According to historical records, the Emperor instructed his royal physicians to grind up smallpox scabs and blow them into his children’s nostrils to protect them against smallpox. The practice later gained its own name: inoculation, referring to the process of exposing an absorptive part of the skin to an infectious agent in order to induce immunity against that infection.

The inoculation method was most utilized against smallpox, so much so that it gained its own name: variolation. Variolation refers to inoculation with smallpox matter, since variola is the name of the smallpox virus. The same practice was also recorded in India, Turkey, and Africa before becoming widespread all over the globe. In 1777, George Washington made it mandatory for all American soldiers in the American Revolution to be variolated. However, variolation was not the ultimate weapon against smallpox. Around two to three percent of variolated patients still died from this disease, and variolated individuals could still carry and spread the disease to others. The journey to find effective protection against deadly diseases continued.

(Source: National Portrait Gallery)

Exit Emperor Kangxi and George Washington, and enter Edward Jenner. In 1796, the English physician scratched the fluid of a cowpox blister into the skin of an eight-year-old boy. Cowpox virus, as the name infers, is a cattle disease that is closely related to human smallpox. The eight-year-old boy recovered after a few days, and once exposed to smallpox again, did not seem to be infected. Further research and studies led Jenner to the conclusion that infection with cowpox can subsequently protect a person against smallpox, and he named the process vaccination. This discovery, like many other innovations before it, was initially rejected and discredited. Fortunately for future generations, Jenner did not give up. History witnessed him gather more and more support. By the beginning of the 1800s, vaccination was introduced to the world.

Following Jenner’s success was that of Louis Pasteur, who developed the rabies vaccine in 1885. The twentieth century arrived and brought with it a new era of innovative techniques for vaccines. Recombinant DNA technology and delivery techniques lead to the discovery of antitoxins and vaccines against cholera, plague, typhoid, tuberculosis, and more. By 1980, smallpox was declared eradicated — the first victory of humankind against infectious diseases. By 2011, rinderpest was no longer a threat. Today, polio, measles, mumps, and rubella are well on their way to join the list of eradicated diseases from the World Health Organization (WHO).

These victories represent a beacon of hope not only for researchers and scientists, but also for everyone around the world that one day, humankind will finally break free of the deadly grip of vaccine-preventable diseases, from measles to COVID-19.


Speaking Plainly:

  • The first record of using toxic substances to train one’s own immune system was King Mithridates VI.

  • In the late 1600s, China recorded one of the first attempts at inoculation; the practice was later found in many other parts of the world.

  • In 1777, George Washington required his soldiers to be variolated during the American revolutionary war.

  • In 1796, Edward Jenner carried out the first experiment for the smallpox vaccine.

  • In the early 1800s, vaccination became popular around the world.

  • Smallpox was eradicated in 1980 — the first infectious disease to be wiped out by vaccination.