Up to 90 percent of people tested for COVID-19 in Massachusetts, New York and Nevada in July carried barely any traces of the virus and it could be because today's tests are 'too sensitive', experts say. Health experts say PCR testing - the most widely used diagnostic test for COVID-19 in the US - are too sensitive and need to be adjusted to rule out people who have insignificant amounts of the virus in their systems because they're likely not contagious. Today the PCR test, which provides a yes or no answer if a patient is infected, doesn't say how...