A study by researchers at Northwestern University and Stanford University published in the journal Nature followed the movements of 98 million people to try to understand what strategy to implement to combat the spread of Covid infections by trying to prevent them.  The study found that restaurants, gyms and hotels carry a higher risk of spreading the virus but, despite this, scholars do not believe the lockdown is necessary.

 Examples of Chicago and Miami

 American scholars through the aforementioned tracing have managed to create "infection patterns", for example in Chicago the reopening of restaurants at full capacity would generate almost 600 thousand new infections: "These data show us where there is vulnerability" said Eric  Topol of the Scripps Research Translational Institute.  Still remaining in the city of Illinois and in terms of restaurants, it is emphasized how a limit of simultaneous entries (capacity at 20%) can reduce the expected new infections by 80%, which is why the extreme solution such as the lockdown is considered unnecessary.  American scientists suggest that measures of this type, targeted and studied according to the situation, are much more effective.  From restaurants through to hotels, infections in Miami peaked during the Spring Break period (beach parties), but the curves dropped significantly with the entry into force of the blockade measures.