“The best tool we have right now in this response is to give individuals breathing room from one another,” Jason Schwartz, an assistant professor in the department of health policy at the Yale School of Public Health, said. “This is really critical.”
The coronavirus is known to spread from person to person through droplets from a sneeze or cough, which can travel about 6 feet.
When healthy people inhale those droplets, or get them on their hands and then touch their eyes, nose or mouth, they can become infected, too, continuing the cycle of spread.
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Enter the need for social distancing, a tried and true public health strategy that goes back centuries.
“It takes out the accelerant for outbreaks that comes when individuals are crowded together, with interactions between the sick and the healthy,” Schwartz told NBC News.
“Social distancing is a way to calm the pace at which an outbreak is able to spread across a population,” he said.
History shows us it works, notably during the 1918 influenza pandemic.
When the first cases of flu were reported in Philadelphia on Sept. 17, 1918, authorities “downplayed their significance and allowed public gatherings to continue,” according to a 2007 study in the Proceedings of the National Academy of Sciences.
Those public gatherings included a large parade in the city on Sept. 28. By the time officials in Philadelphia changed course and started closing schools and limiting large crowds on Oct. 3, it was too late. The virus had spread unchecked through the city, and its hospitals were inundated with nearly 50,000 cases. In the end, 12,000 people in Philadelphia died.
By contrast, the study found immediate social distancing in St. Louis lead to a much different outcome. The first cases in that city were reported on Oct. 5, 1918. Authorities worked quickly, implementing social distancing strategies within just two days.
The speedy action translated into just 1,700 deaths in St. Louis, and far fewer influenza cases than Philadelphia.
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That was two decades before the first flu vaccine was developed, and those in public health have learned much about outbreak control in the interim.
One of the first steps in controlling an outbreak is to identify who is sick through testing. That way, public health officials can isolate those people, treat them, track down their close contacts, and isolate those contacts.