Covid-19 testing: Everything you know about Covid-19 tests, interpreting results, reliability Tests are useful when used correctly, and when you know the limits of the information they give you. Dec 15, 2020 14:20:01 IST Testing is essential to controlling the coronavirus. Once people know they are infected, they can isolate, alert others of the risk and stop the spread. But months into the pandemic, many people still are frustrated and confused about virus testing. Long lines at testing sites, delays in getting results and even surprise testing bills have discouraged some people from getting tested. Many people don’t understand what a test can and can’t tell you about your risk — and wrongly think a test result that comes back negative guarantees they can’t spread the virus to others.