Last month, the Biden administration made a pledge to donate 80 million COVID-19 vaccines to countries in need by the end of June. On Thursday, the White House coronavirus response coordinator gave an update: 40 million doses will have shipped out by the end of this week to more than 40 countries. The US leads the world in vaccine donations, but experts say the pace must to pick up, as much of the world’s population still lacks access to vaccines, and as a more transmissible variant burns through unvaccinated communities.