It’s been more than a month since Gavin Newsom announced that California would go into a lockdown. Now that the daily additional cases have started to plateau, people are wondering when they can be free to roam the streets once more.The following image shows the number of new cases per day for a variety of countries. It is clear that the US is plateauing and the daily increase is starting to decrease, but note that the increase is still more than 20000 people per day. If states let people out now, it may quickly reverse the plateau.
So when should states let people be able to roam the streets again? Well it depends on two things, the daily increase, and what precautions people take. Ideally, a state should reopen when the daily case increase is 0, however, it will require a very long time. Time which politicians and citizens are not willing or able to wait. Then it must be up to balancing the risks. By extending a lockdown, the daily increase will continue going down, but many people, especially those on the brink of financial collapse, will continue to suffer. However, by ending a lockdown early, the daily increase may go back up and potentially require another lockdown. This dilemma is up to statisticians and doctors to figure out.However, there are ways that people can do to hasten the removal of the lockdown. For example, many counties in California require its people to wear face masks when outside. This means that if the lockdown is removed but the rule remains, the increase in daily cases will be much smaller, thus decreasing the risk associated with reopening.Assuming states do not mandate its people to wear face masks or do any other kind of risk mitigation, it is quite easy to estimate when states may reopen. Since the cases in the US are plateauing, and assuming the curve is similar to that of China, we have about another month of lockdown. This means that the US would see many state reopenings around mid May. If the US curve is similar to that of Italy, it may mean that states will reopen in June or even later. However, if states actually integrate many measures to slow the spread of Covid 19 in the public, it becomes much harder to estimate when states will open. It can be as quick as the end of April, which is when most state lockdown orders are scheduled to end.So in essence, the reopening date of states in the US is still hard to guess, but if we follow the trends in China, most states can reopen as soon as mid-May, but if we follow the trends in Italy, states can reopen as late as June or July.