Transcript for Urgent need for reliable antibody testing
There has been so much talk about antibody testing. New results for New York tonight, after the world health organization said there's no proof yet that antibodies mean you have immunity. What is the hope here? If we do have immunity, for how long? What we've seen in other viruses and the common cold. Here's Kaylee Hartung. Reporter: Tonight, states laser focused on testing, expanding screening for covid antibodies. New York has run 7,500, nearly 15% testing positive. 5,000 more on the front lines will be tested, including emergency workers and police. NYPD was out there every day and they paid a terrible toll. Reporter: In Miami, researchers estimate 165,000 have antibodies indicating prior infection, dwarfing the entire state's known cases of roughly 30,000. But accuracy is an issue. A new study of 14 coronavirus antibody tests found only three delivered consistently reliable results. I worry a lot that people are going to draw conclusions from some of these tests that they may not be accurate. Reporter: The W.H.O. Warns even if you have antibodies, there's still no conclusive evidence of immunity. I think what W.H.O. Was saying, we don't know how long that effective antibody lasts, and I think that is a question that we have to explore. Reporter: While it's unknown whether there's immunity to covid, with sars it's estimated to be 24 months. In the common cold and flu, just six. But people with antibodies may be key to treating the most critically ill. That's why I donated plasma after recovering. I just can't believe that I have the ability to do something that could be so helpful. Just 2 1/2 weeks ago, Jimmie Hayden was in a coma and given a dose of experimental plasma. In my heart, the plasma did it. Reporter: Today back home with his wife and four kids, meeting the man they credit with saving Jimmie's life. David, I just can't -- I can't -- I can't put all the words together to say thank you. I was happy to do it, and I'm glad you're well. Just know that you're our hero. I love that, seeing the donor and patient brought together. Plasma donations can help up to four people, and the red cross just contacted you? Reporter: Yes, they said it's been processed, and is helping three people. I'm scheduling another donation in three weeks. Kaylee, thank you. There is also talk about
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