The FDA is meeting Thursday to decide on emergency use authorization for the Pfizer COVID vaccine. New FDA analysis of Pfizer’s data confirms that the vaccine is highly effective at preventing COVID infections, maybe even with a single dose. Today, we discuss the science behind the vaccines and how and when they may change our battle against the pandemic. Our guests are DREW WEISSMAN, professor of medicine at the University of Pennsylvania, whose collaborative research helped pave the way for the new mRNA vaccines, andoffit.com/"> PAUL OFFIT, a pediatrician at Children’s Hospital of Philadelphia who also serves on the FDA Vaccine Advisory Panel.