Some diseases never infect the same person twice thanks to immunity.
Artificial immunity is the idea behind vaccines and people have been trying to achieve it for hundreds of years.
Some historians believe the Chinese inoculated themselves against smallpox as early as the year 1000 AD.
But the founder of immunology in the West is considered to be Edward Jenner. In 1796, Jenner took pus from a cowpox sore on a milkmaid’s hand and deliberately infected a young boy with it.
Months later, he exposed the boy to smallpox, which is a related virus, and found the boy had developed an immunity to the disease.
Jenner’s early methods went through medical and technological changes over decades and ultimately led to the elimination of smallpox in 1979.
Below is a timeline of key dates in the development of some of history’s most important vaccines.
There have been countless advancements in immunology over the years leading to the production of vaccines for dozens of diseases.
According to the Centers for Disease Control and Prevention, vaccines help the human body develop immunity to a disease by imitating an infection.
There are five main types of vaccines young children commonly get in the U-S.
- Live, attenuated vaccines
- Inactivated vaccines
- Toxoid vaccines
- Subunit vaccines
- Conjugate vaccines
