Transcript for Study shows possible new lifesaving coronavirus drug in UK
Now to the coronavirus. The very real concern here in the U.S. And tonight, perhaps the most promising treatment for the virus yet. The uk's oxford university now reporting a low-cost common steroid readily available here in the U.S., too, has cut the death rate in some of the most severe cases by a third. Here's ABC's Maggie Rulli tonight. Reporter: Tonight, a major potential breakthrough in the fight against coronavirus. The first drug that improves survival rates in the sickest covid-19 patients. It's a really important first step. It shows what can be done and it's shown wit a treatment that could be used immediately. Reporter: This doctor and his team at the university of oxfordice covered that dexamethasone, a common steroid, was shown to cut the risk of death by a third for patients who are on ventilators. And reduce deaths by 20% for those who are on oxygen. When somebody comes off a ventilator, do they come off the ventilator dead or alive? And we've improved their chances of coming off that ventilator alive. Reporter: The team worked in near record time, setting up what's believed to be the world's biggest trial of existing treatments in just weeks. Today's results are so encouraging, British doctors began treating patients with the drug today. It's really important, because the drug itself is very widely available. It's available throughout the world and it is extremely cheap. Reporter: In fact, dexamethason can be used in the U.S. For just a dollar a day. For Scott krakower in New York, he says it was a turning point in his fight against covid-19. Within hours of taking the drug, he says he began to feel better almost immediately. This was, like, a big -- a big difference. A huge difference after I went on the IV steroid. Reporter: It is a steroid that reduces inflammation and appears to reduce the virus's effes on lungs. It's different from another virus treatment, remdesivir, which speeds up recovery time, but hasn't shown benefit in improving recovery rates. News on that steroid very promising, Maggie, with us. And there's a new study tonight that just came out about how quickly the virus can spread, particularly among those under 40? Reporter: Yeah, David. This is an alarming new study out of Japan that shows people ages 20 to 39, even those without symptoms may be the ones that are driving the spread of this virus outside of hospital. The study documents multiple cases where just one young person was able to trigger an infection cluster that infected five or more people in places like restaurants, bars and gyms.
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