If there were 5000 new cases on the first week, the total for the second week is 1/2 * 5000 cases = <<5000*1/2=2500>>2500 cases.
The total number of new coronavirus cases in the three weeks is 2500 cases + 5000 cases + 2000 cases = <<2500+5000+2000=9500>>9500 cases.
#### 9500