used quite well. what's your feeling about their general level of accuracy? >> it's a terrific question. the rapid tests are very accurate if your goal is to ask the question, am i infectious right now? and for that question, they're extremely accurate. we continue to compare them to medical diagnostics which are not designed to give you an immediate result, and instead you get greater sensitivity, but they can be sensitive for a very long time, continuing to tell people if they're positive even after they're infectious. so these rapid tests don't do that. they tell you, am infectious right now, and if so, that means you should be isolating because you don't want to spread to other people. >> i think that's a great way to frame the question, and that's where it does seem so crucial in transmission. i have to say i've used them a bit -- first of all, for folks who haven't used them, they're like pregnancy tests, you do a