masking and testing that will help keep people safer. >> doctor blackstock, i want to ask about the work force. last week we saw the cdc reduce the isolation time for health care workers. now they're under pressure to do the same for more workers. a professor from harvard said it's shortsighted not to apply this more broadly. schools, colleges, sports, broadway, restaurants, airlines, all are facing the same problem with having to isolate people for extended periods without the option to test to return. doctor, what do you say? do you agree? >> well, you know what? i disagree. i actually think that what we're seeing are high transmission levels in the community. this is why people are getting infected. in the community and at work. so i think we should focus on policies that create safer environments. so we need to encourage mask wearing. we also need to make sure people have testing available. that people have paid sick