"Summary: The Diamond Princess cruise ship is the largest controlled COVID-19 coronavirus infected population outside of China"
20% of the ship were infected over three weeks
From this, it suggests the rate of officially reported infections (largely in China) is likely too low
And 14 days might not be long enough to conclusively prevent COVID-19 transmission, from the Diamond Princess experience, although passengers have now been released
This is not the news the world would wish for.