Human Upgrades✓✓ 2 independent sources
Smallpox: the only human disease ever eradicated
~300M deaths in the 20th century → 0 cases since 1977; eradication certified 1980
The WHO intensified campaign relied on ring vaccination — isolating outbreaks and vaccinating contacts rather than mass campaigns alone. The last naturally occurring case was in Somalia in October 1977; the World Health Assembly certified global eradication on 8 May 1980. Estimated 20th-century deaths: around 300 million.
One disease has been wiped off the face of the Earth by deliberate human effort: smallpox. Last natural case, 1977. Declared dead by the World Health Assembly, 1980. It killed ~300 million people in the 20th century alone.