UPDATE: Antibody Testing

      Antibody Testing

      An update to our interview with Stanford scientist Jay Bhattacharya who worked on one of the first coronavirus antibody studies.

      Sharyl: Early results in Santa Clara County, California show up to about four percent of people, 81,000, had Covid-19 without knowing it. So the true number of infected could be 85 times higher than officials reported.

      More studies are producing similar results. In Miami-Dade County, Florida, about 6 percent have been infected, more than 16 times what had been reported.

      In New York State, almost 15% tested positive for antibodies. In New York City, nearly 25%.

      Some say these test results are unreliable. However, they are in line with published research as far back as February when a study found 81% of coronavirus infections may not be detected.

      In March, a study estimated 86% of coronavirus infections are so mild they are never diagnosed.

      One reason it matters, it makes the death rate much lower than figures released to the public all of these weeks.

      By way of example, when the U.S. recently hit one million documented cases and 53,928 deaths, the fatality rate was 5.4%. But that could be more than seven times too high because it ignores the undiagnosed cases. Factoring in those for a more accurate figure slashes the death rate to about three quarters of one percent.

      New York is testing thousands of police, fire department, health care and transit workers for antibodies. And Georgia- they’re now testing in two counties.