We've only ever eradicated two infectious diseases in all of human history, smallpox in humans and rinder pest,

variations of which plagued cattle and deer and wild beasts and other even-toed

undulates for most of history, before ultimately being officially eradicated in 2010, a century

after the development of an early vaccine for it in 1918.

Smallpox was likewise eradicated after the development and successful widespread distribution of a vaccine,

early versions of which were developed in the late 18th century, and more advanced versions of which were distributed worldwide, beginning in 1950.

This eventually led to the official eradication of smallpox in humans in mid-1980, so that's

zero official cases globally, down from 50 million official cases each year in 1950, a pretty substantial drop that was the consequence of both

technological developments and the emergence of global systems of distribution and funding,

like the United Nations, which allowed for a more holistic view of global society and enabled

a macro approach to these sorts of issues, rather than the localized

approach that struggled with the realities of pathogens that don't respect man-made borders.

We're still in the process of trying to eliminate polio, which washed across human society

and often quite devastating epidemics since prehistory.

There's Egyptian artwork that seems to depict people who have come down with the paralytic version of this disease.

But polio has been reduced in scale substantially since the emergence of an early vaccine for it in 1950,

followed soon after by an oral version of that vaccine,

which, like with smallpox, did well in individual communities, but really took off once larger

globe-spanning organizations and systems, made an ardent effort to tackle it.

In recent years, only a few hundred polio cases have been detected

worldwide annually, and though those numbers have increased recently, in part due to people who

are fearful or skeptical of vaccines in various places, the organizations working to eradicate

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