William Foege, the mastermind behind the world’s eradication of smallpox, died aged 89. The disease was among the world’s deadliest: It killed around a third of those infected, and as recently as 1967, there were an estimated 15 million cases worldwide. But Foege’s strategy of “ring vaccination” — inoculating close contacts of a case — helped control outbreaks efficiently. The last recorded case was in 1977.
Foege also led efforts to end polio, and said in 2013 that the project was close to success. That victory, though, may be further off: A senior US health official recently argued that the polio vaccine does not reduce the disease’s spread, part of a wider vaccine-skeptical shift in the Trump administration.