One single concept is needed to the general public to try and understand why all the fuss from governments worldwide: the Basic Reproduction Number must be lowered to < 1 to contain the disease and the Covid-19 Number is estimated at about 2.5 right now, which poses a risk because no vaccine still exists and health services may collapse under the strain of increasing people requesting intensive care. More about the Number here: <a href="https://en.m.wikipedia.org/wiki/Basic_reproduction_number" rel="nofollow">https://en.m.wikipedia.org/wiki/Basic_reproduction_number</a>