Abuja, Nigeria
No more wild polio: The entire continent of Africa is now free of wild polio, after it was announced this week that a massive vaccination campaign had eradicated the paralytic disease from Nigeria. It’s a huge win for health-care workers in the country, which accounted for more than half of all global cases less than a decade ago. The last area to be vaccinated was Borno state in northern Nigeria, where Islamist terrorist group Boko Haram held sway and vaccination teams had to brave the insurgency. The wild strain still circulates in Afghanistan and Pakistan. And every year, hundreds of African children are infected with vaccinederived poliovirus, a mutated form of the disease that can spring up in areas where there is only partial vaccination coverage.