With demand for COVID-19 vaccines outpacing the world’s supplies, a frustrated public and policymakers want to know: How can we get more? A lot more. Right away. The problem: “It’s not like adding more water to the soup,” said vaccine specialist Maria Elena Bottazzi of Baylor College of Medicine. Makers of COVID-19 vaccines need everything to go right as they scale up production to hundreds of millions of doses — and any little hiccup could cause a delay. Some of their ingredients have never before been produced at the sheer volume needed. And seemingly simple suggestions that other factories switch to brewing new kinds of vaccines can’t happen overnight. Just this week, French drugmaker Sanofi took the unusual step of announcing it would help bottle and package some vaccine produced by competitor Pfizer and its German partner BioNTech. But those doses won’t start arriving until summer — and Sanofi has the space in a factory in Germany only because its own vaccine is delayed, bad news