so will full approval convince more americans to get their shots? check out this recent poll by the kaiser family foundation. 3 in 10 unvaccinated adults said they would be more likely to get a vaccine if it was fda approved. joining us now is dr. irwin redlener, the founding director for the national center for disaster preparedness at columbia university and an msnbc public health analyst. dr. redlener, can you start explaining what the difference is between approval and emergency use authorization? is it basically the same project but one just takes more time, or is there more to it than that? >> there's a little more to it than that, joshua. but the deal is that emergency use authorization is really designed to -- to respond in a serious public health crisis, so without waiting for the full approval. on the other hand it's a thorough vetting of safety and efficacy issues which go onto