Transcript for COVID-19 vaccine could be available by December
Now to that potential light at the end of the tunnel.the promise of a vaccine. Tonight, the nation's vaccine czar says the first Americans could get it in just three weeks. In the meantime, a major step forward in treating covid patients. The fda green-lighting regeneron. Here's Stephanie Ramos. Reporter: Tonight, the chief scientific adviser of operation warp speed saying the first Americans could be vaccinated against covid-19 as soon as December 11th, just 19 days from now. We are ready to start shipping vaccines within 24 hours from approval. And hopefully people will start to be immunized, I would say, within 48 hours from the approval. Reporter: The fda announcing it will have a public hearing for pfizer's request for emergency use authorization of its vaccine on December 10th, and it could be recommended for emergency usa authorization that day. Moderna's vaccine will face the same review a week later. Until vaccines are widely available, promising therapeutics getting the green light. This weekend regeneron, the same antibody treatment used by the president, was granted emergency use authorization by the fda for people ages 12 and over, and for those at higher risk of developing severe illness from covid. The drug, genetically engineered in a lab, imitates the body's natural defenses. Just one dose, delivered through an IV, has so far been shown to prevent so infected people from developing severe disease. It gets to work right away, blocking the virus from entering and infecting healthy cells, earlier this month, Eli Lilly's antibody drug also receiving emergency use authorization. I'm on day two outside the infusion. I'm having some fatigue, but that's improved. Reporter: We've followed Dr. David Schultz in Indiana, one of the first covid patients in the country to receive the drug, since he began his treatment nearly two weeks ago. I have no cough, no congestion. Reporter: And just today, Dr. Schultz telline appears to have a full recovery. We are very grateful to all those doing research, those who have worked on the vaccine development, and those who are working in our hospitals, and around all the clinics around the country. Encouraging news. Stephanie, the doctor also predicting today that if 70% of Americans take the vaccine, we could see herd immunity as early as may? Reporter: Absolutely. But it will take months before enough doses are available for all Americans. And also, scientists fear convincing people to take it will be tough. A recent poll finding more than 40% of Americans are hesitant to take an FDA-approved vaccine. Much of it having to do with the political context under which the vaccine was created. Tom? Stephanie, thank you.
This transcript has been automatically generated and may not be 100% accurate.