I haven’t seen it for Knox County either but I have seen it for Oak Ridge. For OR it wasn’t even a kid who tested positive, it was a kid “showing symptoms” so they forced that kid and everyone they identified through contact tracing to quarantine for 14 days (I think it was right before the 24 day info came out) and the kid with symptoms couldn’t return until he had a negative test. I think the others identified also had to have a negative test to return but I’m not 100% sure on that part. I don’t know that Knox County handles it the same way but I wouldn’t be surprised one bit.