For instance, if you only get a very faint line, it might be hard to know whether or not that means your results are positive. I know how that feels firsthand. After more than two years of evading ...

Abundant, free, rapid tests, many experts argue, are vitally important for mitigating what we know is fast becoming an endemic virus — Covid-19. But that is easier said than done. Between supply ...

At-home rapid COVID-19 tests can reveal more about viral load than a simple positive/negative result, according to experts. "By definition, the basic technology suggests that you somehow have to go ...

With Covid-19 cases up across the country, many people are once again relying on home tests to guide decisions about going to work and sending their kids to school and other activities. A lot of those ...

The Washington Post is providing this story for free so that all readers have access to this important information about the coronavirus. For more free stories, sign up for our Coronavirus Updates ...