These go hand in hand. In the US we cannot slow the spread because we refuse to test anyone who doesn't need acute care or who doesn't have documented contact with travelers or foreign nationals. The research from Helen Chu's lab at University of Washington shows that this means we missed the start of community transmission entirely in Washington.

Here, there are health care workers who can't get a test! They deal with people with significant health problems every day and could be spreading it all over -- but because they didn't travel, they can't get a test.