Four countries have contained their #covid19 outbreaks: China, Singapore, Taiwan, and South Korea. The last three did it without closing schools, churches, bars, or any non-essential businesses. They did it without lock-downs and without banning all gatherings. How?? As noted by @tomaspueyo, the core of the most effective #covid19 containment strategies was Test Track Publish: (1) test everyone, multiple times; (2) track every infected person; and (3) publish all the data so everyone knows what's going one. Why does this work?