It does sound extremely over the top indeed, but it might be the only way to prevent the spreading. It appears that by the time you find the first case, you are

It does sound extremely over the top indeed, but it might be the only way to prevent the spreading. It appears that by the time you find the first case, you are too late as the virus has been spreading all over the place. Maybe quarantining everybody, even from area with zero cases, is too much... but at least people should make a strong effort to reduce social activities for a few months.