Dr. Anthony Fauci, the country's foremost infectious disease expert, tells NPR that it's "OK to celebrate" the good news about Moderna's coronavirus vaccine, but warned it's not the time to back off on basic health measures. The biotechnology Moderna Inc. said Monday that its experimental vaccine was 94.5% effective in preventing the disease, according to data from its clinical trial. "From a scientific and potential public health standpoint, this is an extraordinarily important advance," Fauci told Rachel Martin on Morning Edition Tuesday. The Moderna study has 30,000 volunteers who either got a placebo or the vaccine. There have been 95 people who happened to get sick with COVID-19. But 90 of the people who got sick didn't get the vaccine; of people who got vaccinated, only five got sick. A week earlier, Pfizer said its vaccine was more than 90% effective in its own trial. The Food and Drug Administration set a minimum effectiveness of 50% . Fauci said a few months ago he would "like