Health Trump knew testing Covid-19 vaccines would take months, Woodward book shows Share Tweet President Donald Trump knew back in the spring that it would probably take a year to develop a coronavirus vaccine, according to interviews with journalist Bob Woodward. Related Topics: Advertisement Click to comment Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment Name * Email * Website Save my name, email, and website in this browser for the next time I comment. Advertisement