500 Million, But Not a Single One More

Smallpox. It's about the eradication of smallpox.

Smallpox was able to be eradicated because it’s a disease that people only get once, and which does not have an animal reservoire.

The smallpox vaccine was intradermal, rather than intramuscular. Resistance to inoculation was reduced because it was just a scratch, rather than an injection.

The elimination project concentrated its efforts on outbreaks. Dr. William H. Foege developed a “ring vaccination” strategy to target vaccination around outbreaks rather than mass vaccination.

Nice story. Here's two little tidbits regarding humanity's fight against smallpox. Catherine the Great let herself be "variolated" in 1768 by Thomas Dimsdale. Following her example, two million Russians underwent the procedure in the next 3 decades [1]. On the other side of the world, George Washington mandated this procedure to all his soldiers in 1777 [2]. Some people think this contributed to the colonists eventual victory against the British.

[1] https://historyofvaccines.org/blog/empress-immunization-how-...

[2] https://www.nps.gov/articles/000/smallpox-inoculation-revolu...