Britannica
Sources used in this answer
How did vaccination differ from variolation?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
smallpox
Edward Jenner vaccinating his child against smallpox; colored engraving.
Vaccination and variolation were both historical methods used to induce immunity against smallpox, but they differed significantly in their safety and biological approach.
- Variolation: This method involved infecting a healthy person with material taken directly from the sores of a patient suffering from a mild case of smallpox. While it often resulted in a less severe form of the disease, it remained dangerous because recipients could still develop full-blown smallpox and potentially spread the infection to others.1
- Vaccination: Developed by Edward Jenner in 1796, this method used material from cowpox, a much milder virus. Because cowpox and smallpox share common antigens, the cowpox infection successfully activated the immune system to provide immunity against smallpox without the risk of the patient contracting the deadly disease itself.12
Ultimately, vaccination proved to be a safer and more effective practice, leading to the eventual global eradication of smallpox in 1980.1