A study backed by Mark Zuckerberg reveals companies are selling antibody tests for the coronavirus with big potential for error

· A study backed by the Chan Zuckerberg Biohub found several companies are offering antibody tests for the novel coronavirus with less than 90 percent accuracy. 
· The accuracy of the tests varies depending on how they're used.
· It's the latest report to indicate that antibody kits with varying levels of accuracy are...