The international race for a COVID-19 vaccine boils down to a couple important questions: How a lot should the pictures rev up anyone’s immune gadget to in reality paintings? And may just revving it the unsuitable approach purpose hurt? Even as firms recruit tens of 1000's of other folks for greater vaccine research this summer time, in the back of the scenes scientists nonetheless are trying out ferrets, monkeys and different animals in hopes of clues to these fundamental questions — steps that during a pre-pandemic generation would had been completed first. “We are in essence doing a great experiment,” stated Ralph Baric, a coronavirus knowledgeable on the University of North Carolina, Chapel Hill, whose lab is trying out