More than 40 million doses of the coronavirus vaccine have been administered in the U.S. so far. But to end the pandemic, scientists say we will need to vaccinate a substantial portion of the global population — not just Americans.

Here & Now's Callum Borchers checks in on vaccination efforts around the world with three NPR reporters: Rob Schmitz in Berlin, Eyder Peralta in Nairobi, and China correspondent John Ruwitch.