“The study, which was published in the journal Nature, used cellphone data to track the hourly movements of 98 million people from 57,000 neighborhoods to points of interest, like restaurants, churches and stores, for two months, starting in March. The location data, which was collected by SafeGraph, a company that aggregates anonymous location data from mobile apps, came from 10 of the largest U.S. cities, including Chicago, Houston, Los Angeles, New York and Philadelphia.
The research team then compared those movements with COVID-19 case counts for each area. Next they used a model to simulate different scenarios, like reopening some venues while others stayed closed. The researchers also estimated COVID-19 infections based on restrictions, or lack thereof, in these areas.Overall, the researchers determined that opening restaurants at full capacity led to the largest increase in infections. Opening gyms, cafes, hotels and motels at full capacity also created a jump in infections.”
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“It’s not all doom and gloom: The researchers found that putting a 30 percent occupancy cap on all venues could dramatically decrease infections. Infections were further decreased when the cap was at 20 percent.
It’s important to note that this is a model — it didn’t definitively link cases to these spots. Instead it found that the locations are likely to contribute to the spread of the virus.
But there have been real-world examples that suggest the latest findings are onto something. In October, an indoor spin class in Canada was linked to at least 69 cases of COVID-19. In May, the Centers for Disease Control and Prevention shared a case report detailing how up to 87 percent of the members of a choir in Washington state became infected after a 2.5-hour practice alongside a member with COVID-19 who was asymptomatic. And a report published by the CDC in September found that adults who tested positive for COVID-19 were twice as likely to have reported dining out at a restaurant than those who did not contract the virus.”