THE RECORD
What changed
The last naturally acquired case was identified in Somalia in 1977; WHO declared eradication in 1980.
EVIDENCE
What remains
Surveillance, laboratory confirmation, vaccination records and certification reports establish eradication.
WHY IT MATTERS
Why it matters
It was a rare public-health success built by field investigation, local workers and trust as well as vaccine.
OPEN QUESTION
Where interpretation begins
A humanity-wide claim can erase local labour and suffering; retained virus stocks remain debated.