The number of confirmed COVID-19 cases in the US has grown to 1,698 (Mar 12, midnight GMT).  This number is much lower than the tens of thousands of cases that are probably already active in the US due to substantial under testing.  A number of areas in the US are now experiencing concentrated exponential growth of COVID-19.  These areas need to isolated immediately.  New Rochelle, NY has been “contained” but this is not enough.  Too many infections have already leaked out or begun in the rest of metro-NYC as people have traveled and congregated freely, and allowed the virus to proliferate.  NY state has 328 cases identified in just the last 12 days — much of it in metro-NYC.  All of metro-NYC should be contained, if not quarantined.  NYC, however, is not the only hot spot in the US. 

New York3280
New Jersey301

Washington state has more than 420 cases and a hot zone around Seattle that must be contained.  California with 252 cases has two hot zones around San Francisco-Silicon Valley and Los Angeles that should be contained.  Finally, Massachusetts with 108 cases has a hot zone around Boston that needs to be contained.  These five metro areas should cordoned off and controlled as soon as possible.  In addition, other infected areas around DC, Miami, Atlanta, Denver, Philadelphia, etc. should be preparing to implement congregation and travel restrictions now.