Transcript for Western scientists skeptical of Russian vaccine for COVID-19
Overseas tonight, news from Russia. Vladimir Putin says they have a vaccine for covid, that his daughter has been given the vaccine. Of course, the media questions, among them, how safe is this vaccine? Here's our senior foreign correspondent Ian Pannell tonight. Reporter: Tonight, Russia claiming a major victory with the world's first approved coronavirus vaccine. President Vladimir Putin even saying one of his daughters has been given the inknock lake they're nicknaming sputnik vaccine. The efficiency has been developed. 100% of the people developed immunity. Reporter: But many scientists in Russia and around the world saying it simply hasn't been properly tested. Russia choosing to go ahead, before completing that crucial final phase three trial that's used to show if a vaccine will work safely in a large population. They only lined up 2,000 people for that final step. Compare that to the tens of thousands now being tested with vaccines being developed by modern, pfizer and oxford, all of which are further along in trials than Russia. Dr. Fauci shared his reaction with national geographic. I hope that the Russians have actually definitively proven that the vaccine is safe and effective. I seriously doubt that they've done that. Reporter: Dr. Fauci telling David he's optimistic there will be an effective vaccine around year's end. I believe there's a good chance we will. That should take by the end of this calendar year with vaccine available as we go into 2021. Reporter: President trump now announcing that the U.S. Is buying 100 million doses of the modern vaccine, hoping like others it is proven safe and effective. David? All right, Ian Pannell reporting tonight, thank you. And when we come back here,
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