Two COVID-19 vaccines might be nearing the finish line, but scientists caution it's critical that enough people volunteer to help finish studying other candidates in the U.S. and around the world. Moderna Inc. and competitor Pfizer Inc. recently announced preliminary results showing their vaccines appear more than 90% effective, at least for short-term protection against COVID-19. If those early results hold up and U.S. regulators agree the shots are safe, emergency use of small, rationed supplies could start in late December. Other countries with contracts for early doses would undertake their own reviews. "We're at a point where we're really seeing the promise, where we're seeing that even these new technologies may produce vaccines that are going to help us meet this need," said Dr. Jesse Goodman of Georgetown University, former chief of the FDA's vaccine division. "But we're waiting for more data, more follow up. And even as that becomes available, hopefully in the next couple of months and for other candidates, we also have the issue of having enough vaccine to really make an impact on the pandemic," he added. Subscribe to our YouTube channel: https://bit.ly/2TwO8Gm Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world. To watch complete coverage on Bloomberg Quicktake 24/7, visit http://www.bloomberg.com/qt/live, or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app. Connect with us on… YouTube: https://www.youtube.com/user/Bloomberg Breaking News on YouTube: https://www.youtube.com/c/BloombergQuickTakeNews Twitter: https://twitter.com/quicktake Facebook: https://www.facebook.com/quicktake Instagram: https://www.instagram.com/quicktake