Transcript for Potential third COVID-19 vaccine shows promising early results
volunteers got a half a dose followed by a full dose a month later. A conclusion researchers discovered after they gave some volunteers only half a dose, later learning the vaccine was more effective that way. If you can start with half the dose, we will have more vaccine available, and we can start vaccinating a larger group of people around the world. Reporter: Astrazeneca's vaccine is more affordable to produce and doesn't need to be stored in extreme cold like pfizer's. You can store it in the fridge just like you store the rest of your groceries. Reporter: This all comes after pfizer and modern reported their vaccines were found to be up to 95% effective. Pfizer could get emergency use authorization from the fda immediately following a public hearing on December 10th. Our Bob woodruff today with the general in charge of distribution for "Operation warp speed" asking him how long before the first Americans get this after the greenlight from the fda. 24 hours later, vaccines are on the street, right? 24 hours is all it's gonna take? Yep. Reporter: In the beginning there won't be a choice of which vaccine. Whichever is approved first goes out first. If pfizer is first, I'll call pfizer, and they'll begin distributing vaccines. It will go turisdictions simultaneously, 50 states, 8 territories and 6 metropolitan cities. That was really encouraging to hear and, to getting new information ahe time line for these first vaccines? Reporter: That's right, David. We have new reporting tonight. The secretary of health and human services tells our Bob wo both moderna and pfizer, 40 million doses will be from those companies and that the astrazeneca news is obviously very promising. He also points out it's being made right here in the U.S. So once it's approved, David, it will be ready. Tom llamas and our thanks to
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