Transcript for FDA advisory panel votes to recommend Johnson & Johnson vaccine
Good evening. And it's great to have you with us here as we near the end of another week together. We begin tonight with the news coming in just a short time ago, that key fda panel now recommending emergency use authorization. U.S. Will very soon have a third weapon against the coronavirus. Johnson & Johnson's one-shot vaccine, 3 million to 4 million doses ready to be shipped out right away. The fda advisers, doctors and scientists recommending the vaccine late today in an the big difference with this vaccine, just one shot, and they say it's 100% effective in preventing hospitalizations and deaths and that it was test in the communities with concerning variants and that it still performed well. President Biden in Houston today promising to use every conceivable way to expand manufacturing in this country. Phaser and modern promising to make enough vaccines to give to all Americans by July. Now Johnson & Johnson tonight promising 100 million by June. You do the math and this could boost the pace. Tonight the pictures, the 101st airborne deploying to Orlando to help with FEMA vaccination sites. The head of the CDC just today saying she's very concerned that the number of new cases of the virus are leveling off at a high number, saying the data may reflect, the quote, beginning effects of these new variants. But first tonight, the news just in on the one-dose vaccine. ABC's whit Johnson leads us off in New York tonight. Reporter: Tonight, an imminent game changer in the fight against coronavirus. An fda advisory panel voting unanimously to recommend Johnson & Johnson's one shot vaccine. The maimty voted yes. We do have a favorable vote. Reporter: Clinical studies showing the vaccine provides strong protection. 85% effective against severe illness. 100% at preventing hospitalizations and deaths. And another critical finding -- early data suggesting the shot may also offer 74% protection against asymptomatic infections, making those vaccinated less likely to spread the disease. The fda saying the vaccine had the expected side effects like fever and fatigue. And the company is looking into preliminary reports of two severe allergic reactions as seen in other vaccines. But top health experts calling it safe. We now have three highly effective vaccines. Importantly, each of them are very effective against severe disease, and virtually all of them say that you look at the data and it's clear that you get essentially no hospitalizations or deaths in any of them. This is very good news. Reporter: Unlike the others, j&j was test in the communities with concerning variants and still performed well. The Johnson & Johnson vaccine is Alo easier to store at normal refrigerated temperatures. We need vaccines that are effective and well tolerated and simple to deploy. Reporter: For months, teams inside this lab near Baltimore have been working around the We have been in constant production since. From plants in Louisville and Memphis, up to 4 million doses ready to ship out within day of getting the green light. And 100 million by the end of June. That's when the country could see enough vaccine for all American adults. And by the end of July, modern and pfizer will deliver the last of their 600 million doses which would mean a surplus. I used the defense production act to speed up the supply chain for key equipment that's already helped increase vaccine production. Reporter: But today some health officials concerned about the variants, noting the recent plunge in cases may be stalling with an uptick in the last three days. The latest data suggests that these declines may be stalling, potentially leveling off at still a very high number. We at CDC consider this a very concerning shift in the trajectory. Reporter: Still, the race to vaccinate is picking up steam. The 101st airborne division deploying to Orlando to support vaccination efforts there. And those shipments delayed by the storm now flowing in the northeast. New York adding overnight shifts at mass vaccination sites after getting extra supply. A lot has now come in, so we're going to blitz this week. All of this very earn couraging. Whit with us from a vaccination site at Citi field. The vote today from the fda advisory panel. Walk us through what's in the coming hours. How soon we could see shots in arms. Reporter: Final authorization is expected within the next 24 hours. Then on Sunday, a CDC panel will meet to discuss prioritizing the deployment of this new vaccine. Those first shipments could go out as early as Monday with a potential for shots in arms by Tuesday. David? Whit Johnson, we'll see you at the anchor desk this weekend.
This transcript has been automatically generated and may not be 100% accurate.