From Canada to Singapore to the UK and the US, the Pfizer-BioNTech vaccine has crossed a major milestone this month as it’s started deploying in public COVID-19 vaccine programs. But lots of other vaccine efforts are in the works around the globe, with greater and lesser success. The World’s Elana Gordon talks with host Marco Werman about what else is in the pipeline, what that matters, and some unusual collaborations on the horizon.