If we only knew who had developed immunity to the virus.  Immunity may occur in someone who had the virus (either with symptoms or without), got better and developed IgM and IgG antibodies.  We know that happens.  If you are declared immune, you can safely go back to work which might help the economy.  You are safe as a healthcare worker.  You are safe to go buy groceries. You are safe to be around your loved ones.  You could donate plasma at the local Blood center and plasma with lots of antibodies could be administered to patients dying in the ICU (passive immunotherapy used previously against the Spanish flu and against Ebola for example).

There are some promising reports regarding testing for the presence of antibodies to the COVID-19 virus:

This is ultimately more important than the RT-PCR diagnostic test performed with throat or nasal swabs. This virus has only existed since Dec 2019.  Anyone who has the antibodies was infected since that date.  I assume they are making sure that the antibodies don’t react with previously known Coronaviruses (SARS and MERS).  This will give us great information on what the actual number of infected persons has been.  It will tell us what percentage of the population has not yet been infected and is still susceptible to the virus.  This percentage will be dwindling as the pandemic progresses and the virus runs out of people to infect.  For those that still don’t have antibodies, we might want to think about not having them around susceptible populations, as in a nursing home.  This is an opportunity.  Let’s not bungle it again.  Everyone should get tested!