At the first Global Vaccine Summit the world came together and pledged more than $4 billion to end polio by 2018. When we eradicate polio—and I’m confident that we will—it will be a critical milestone in the Decade of Vaccines, a vision to reach all children with the vaccines they need by 2020. Watch this video about the summit: http://b-gat.es/ZZhjz8 | Bill Gates

Vaccines are a miracle. But how exactly do they work? I explain the science behind vaccines and why our foundation’s investment in Gavi, the Vaccine Alliance is one of the best we’ve ever made: https://gatesnot.es/37uMfA5 | Bill Gates