Francis Collins, director of the National Institutes of Health, told NPR this week that he's "guardedly optimistic" about the prospects of a coronavirus vaccine being approved by the end of the year.In the meantime, scientists are still learning new things about the coronavirus. NPR's Geoff Brumfiel reports on improvements in medical treatment for COVID-19 patients, and NPR's Michaeleen Doucleff explains new research on air travel. In participating regions, you'll also hear a local news segment that will help you make sense of what's going on in your community.Email us at considerthis@npr.org.