Americans in four cities with substantial numbers of COVID-19 infections are heeding calls for social distancing and potentially helping curb the spread of the disease, new data from the U.S. Centers for Disease Control and Prevention (CDC) shows.
“Actions such as social distancing are especially critical when medical countermeasures such as vaccines or therapeutics are not available,” researchers said in the CDC’s Morbidity and Mortality Weekly Report published Monday. The study used community mobility as a proxy for social distancing.
Anonymous location data from devices as people moved around in New York City, Seattle, New Orleans, and San Francisco—four cities with significant numbers of COVID-19 cases—showed a drop in community mobility, or a rise in social distancing.
“Community mobility in all four locations declined from February 26, 2020 to April 1, 2020, decreasing with each policy issued and as case counts increased,” the researchers said in the report.
The report found that, on Feb. 26, around 80 percent of people in the four cities were leaving their homes. By April 1, that figure dropped between 20 percentage points and 40 percentage points in each city, after stay-at-home orders were introduced.
“They didn’t leave their home at any point for any reason. They didn’t go outside. That’s significant,” said study coauthor Kathleen Ethier, in remarks to CNN.
The findings suggest public policy plays an important role in how thoroughly people adopt social distancing measures and “provides some very early indications that these measures might help slow the spread of COVID-19.”
“Public policies to increase compliance with social distancing, including limits on mass gatherings, school closures, business restrictions and stay-at-home or shelter-in-place orders appear to be associated with decreases in mobility,’’ the researchers said.
“However, more information is needed to assess impact on disease transmission,” they said.
An encouraging sign that social distancing measures may be having an effect is that updated mortality models suggest fewer than 70,000 Americans will die from COVID-19, while earlier projections put that figure as high as 2 million.
CDC Director Robert Redfield told Bloomberg in an interview last week that the early models underestimated compliance with calls for social distancing. Early compliance projections stood at around 50 percent, he said, but in the end, “compliance to the message has been in excess of 90%.”
“The American public has adjusted to #socialdistancing in a way never predicted by models. I’ve learned that this behavior modification has saved hundreds of thousands of lives, which is a testament to the American people,” Redfield wrote on Twitter Monday.
“I would beg them to stay with this,” Redfield told NBC News on Monday, speaking about whether people should continue social distancing.
“Behavioral modification is something that, when it’s for our health, we’re not that good. But what I’ve learned about from this outbreak is when my behavior modification helps your health, or saves your life, the American public has done a great job,” he added. “So I would first really beg people to stay with this. We need to really maximize our social distancing. It’s all hands on deck right now. No letup,” he said, adding, “all hands on deck until we’re comfortable the transmission of this virus has not slowed, but stopped.”