jeremy howard, university of san francisco research scientist. a member of world economic forum global council. kind enough to join us via skype. jeremy, maybe you can help me with this, little more than couple weeks ago, we were told save masks for health care workers, average folks walk around really don't need them. what is the real skinny? >> charles, the real skinny is this, super simple. there are hospital masks needed for hospital workers. they do special procedures aerosol generating procedures, spray goes everywhere, you need specially fitted masks. they need them. there is kind of mask you can make at home, don't even need a sewing machine, anybody has to wear the masks to go outside. it is number of one thing we can do to stop the spread of the virus. neil: so, if there is a guideline change, let's say from the surgeon general's office or now the government, i don't know which entity would officially say it is a good idea? i even see, jeremy, more people walking around with these things. i live in a small community. i'm seeing more of
