Transcript for Results from 3,300 antibody tests in a community
We'll stay on it every night. New results in tonight and the world health organization saying it does not have proof that the presence of antibodies means you will have immunity from this. Although that is the hope. What we do know is those antibodies show if you have been exposed to the virus. There's new results on that. Diane sawyer is back with a study of one county in America. Just how many of us in the community have been exposed to the virus, far more people than first thought. What it will say about the rest of the country. What the scientists leading the study are telling Diane tonight. Reporter: The results are in. From 3,300 volunteers tested in Santa Clara, California, just a finger prick, a drop of blood which reveals if you have antibodies left behind because you had the coronavirus. I am so excited to talk to you. What can you tell usbout what you found? Dr. Eran Bendavid of Stanford says when they did the testing, official records showed 1,000 cases of the virus in their county, but he says the study of the antibodies indicates the estimated number could be up to 80,000. Is that more or less than you expected? Our findings suggest that there are somewhere between 50 and 80-fold more infections in our county than what's known by the number cases than are reported by our department of public health. What we're seeing is the tip of a big iceberg. Reporter: He says it will take more research to know how many people with those antibodies never knew they had the virus because they had no symptoms. And here's a reality check -- even if as many as 80,000 people in Santa Clara have the antibodies, that's less than 5% of the total population there. So even if the antibodies offer meaningful protection, 95% could be vulnerable returning to schools or to jobs or to life. We don't know if this confers immunity, we don't know if you still are or if this is really a past infection, if you're currently infected. The most important thing is to keep following public health guidelines. Reporter: Tests from one community, another study underway in Los Angeles and reporting in soon. When we first talked you told me that this was kind of a mission for you and your team to show that we can gather information, we don't have to wait to gather information. Do you still feel that way? Oh, absolutely. Even more so. Reporter: And at the very least, these scientists have shown it's possible to move quickly and carefully and get some real information right now. Diane sawyer reporting Diane, thank you. In the meantime there's also a race tonight for any kind of
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