Transcript for USC reveals preliminary results of antibody study
We've been awaiting the results of a large-scale antibody test in Los Angeles county. Tonight, the results are just in. And in that one county alone, finding the number of covid-19 cases may be 55 times higher than first thought. Here's Kaylee Hartung from California. Reporter: Tonight, the major headline. The actual number of covid-19 infections may be 55 times the confirmed cases in Los Angeles county. Usc testing nearly 900 people for antibodies, now estimating as many as 442,000 in the county had the virus as of April 9th. But that's just 5% of the population. The test finding hidden covid cases, but -- These tests are not good for telling if someone has immunity. Reporter: That's because questions remain about whether antibodies provide immunity. There's an assumption, when you have an antibody that you are protected against reinfection, but that has not been proven for this particular virus. Reporter: While health officials rush to test thousands more in Michigan and New York, critics say the fda is allowing these tests, many coming from China, too quickly before being proven reliable. But one benefit to testing more people for antibodies, their potential to save lives. When plasma from a recovered person is donated to someone who's sick. Connie griffin is a nurse in Ohio. She and her husband both put on ventilators. Her daughter choosing which would get the experimental plasma treatment. In an interview for ABC news live, Connie now able to talk today. Do you think you'd be where you are today if it wasn't for that plasma treatment? No, I don't know that I'd have made it without that treatment. Reporter: Her husband responding to another treatment, and tonight safely home, waiting for her to return. Kaylee, back with us tonight. You've reported on your own recovery from the virus, you've tried to donate your own plasma, and you've hit some hurdles. Where does that stand tonight? Reporter: I have, David. That hospital in Ohio where she received her plasma, it was one of the first hospitals giving out the treatments. I ran into dead ends, I submitted a request 2 1/2 weeks ago, they called yesterday to say that I'm more than 28 days symptom free, I can donate later this week. Kaylee, thank you. Great to see you back on the beat tonight.
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