Albert Bourla, Pfizer's CEO, said it's not clear if the company's coronavirus vaccine will no longer be able to spread the virus to other people.<br />Bourla told NBC's "Dateline": "I think this is something that needs to be examined. We are not certain about that right now with what we know."<br />Independent researchers have already made it clear that the trials used to test the vaccine did not examine its effects on transmission.<br />Business Insider reports the US could approve Pfizer's vaccine on December 10.
