[Keilar:] Breaking news that we are following today, the World Health Organization has temporarily halted studying the Trump-touted drug hydroxychloroquine as a potential treatment for coronavirus, citing safety concerns. Officials made the decision after new findings linked it to a higher risk of death in seriously ill coronavirus patients. Dr. Peter Hotez is the dean of the School of Tropical Medicine at Baylor University, and he's an acclaimed vaccine researcher. Doctor, this is the same drug the president claimed he was taking for preventative measures for two weeks, which he wrapped up last week. But scientists from across the globe are saying that it's too dangerous to even continue in clinical trials with. How significant is that?
[Peter Hotez, Professor And Dean Of Tropical Medicine, Baylor College Of Medicine:] Yes, a lot of this came out of a publication last week in "The Lancet," a group led by a cardiologist that the Brigham and Women's Hospital and the cardiovascular group there. And it was a massive study of over 96,000 patients and multinational registries, two-thirds of them were from North America. And of those 96,000 patients, it showed about a third of those were either randomized to either hydroxychloroquine, chloroquine or hydroxychloroquine with azithromycin. And the results were pretty were not subtle, they were pretty clear that those patients who received any one those arms, had a significantly higher increased of risk of dying in the hospital, increased mortality as well as a very serious type of arrhythmia known
[Keilar:] Unethical to continue, I think that really encapsulates what is going on here. Doctor, we're also learning that Oxford University's vaccine trial only has a 50 percent chance of success, according to scientists. And that's because the number of people with the virus in the United Kingdom is actually falling too quickly, right? You need to have people try a vaccine, and then they need to be subject to it to see if they get it or not. So the lead researcher here was quoted saying, we're in the bizarre position of wanting COVID to stay.
[Hotez:] Yes. Adrian Hill is a longstanding colleague and friend and associate, we've known each other for years. He made that statement. I didn't quite understand it because it was referring to the fact that there may be decreased transmission by the time the vaccine is ready to test in the U.K. But who cares? This is a vaccine that's been licensed to AstraZeneca, it's one of the major vaccines going into Operation Warp Speed I hate the name, but there it is, Operation Warp Speed in the United States, it's probably going to be tested elsewhere internationally, maybe Brazil or elsewhere. So whether or not there's transmission going on in the U.K. should not really matter. So unless he was referring to something else, I would assume that the trials are going to go forward. We we had one result in nonhuman primates that with mixed results in terms of nonhuman primates, but it's moving forward in people. And we should be able to get a pretty good sense, over the coming year and a half, whether the vaccine's working and whether it's safe.
[Keilar:] Yes, we are constantly looking for these bright spots, aren't we? But this is a long road ahead of us. Dr. Hotez, thank you so much for joining us.
[Hotez:] Thanks.
[Keilar:] There are clusters that are breaking out across the U.S., including at a Great Clips store as well as a private school. Plus, the White House has issued new travel restrictions on Brazil, as cases in that country surge to the second-highest total in the world. CNN is on the ground as a war of words erupts between Brazil's president and the mayor of a town that has been forced to dig mass graves.