Understanding How Testing Works

Expanded and frequent Covid-19 testing has emerged as a necessary precondition for reopening America and resuming something like normal life. But political leaders and citizens need a better understanding of how testing works, how testing can go wrong, and why tests don't necessarily indicate immunity to disease. As we move into the next phase of the Covid-19 pandemic, we also need a better understanding of viral antibodies and how serological tests differ from tests for the novel coronavirus itself. Tests can trick us into thinking we were never infected when we were, and vice-versa, which in some cases can present a real danger.