The one disease that the WHO has been able to eradicate in the world is Smallpox.
Smallpox was fatal in up to 30% of cases. Smallpox has existed for at least 3,000 years and was one of the world's most feared diseases until it was eradicated by a collaborative global vaccination programme led by the World Health Organization. The last known natural case was in Somalia in 1977.
WHO coordinates various preparedness and response activities to protect global health from any possible outbreak of smallpox. WHO receives information from governments and other sources on unusual disease outbreaks. It provides technical guidance to help countries respond to these events. WHO has displayed practical information on smallpox diagnosis, surveillance, and outbreak response on its website. It can help countries identify potential sources of the vaccine, should such a need arise.