New trials are ‘the main event’ in race for a coronavirus vaccine, doctor says

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Dr. Ashish Jha, director of the Harvard Global Health Institute, tells TODAY that new vaccine trials by Pfizer and Moderna are “exciting,” but cautions that even after a vaccine is determined to be safe, he is “a little worried” about potential supply chain problems. He says the outbreak of coronavirus on the Miami Marlins baseball team points to the difficulty of “trying to run any business during a large outbreak.”