Thread by @nytimes

Starting social distancing across the U.S. just a week earlier in March could have saved tens of thousands of lives, according to estimates from Columbia University researchers.

Here's how that could have reduced coronavirus deaths city by city. nyti.ms/2TsgDa3

Most social-distancing guidelines in the U.S. were not put in place until mid-March. This map shows how many people died from Covid-19 even with those restrictions in place by May 3. nyti.ms/2TsgDa3

If the same level of social distancing — like closing schools, staying home and avoiding restaurants and crowds — had started just one week earlier, nearly 36,000 lives might have been saved, the researchers estimated.

In New York City alone, 15,000 fewer people may have died.

The change is even more dramatic if social distancing had started 2 weeks earlier.

Under this scenario, nearly 54,000 lives across the U.S. may have been saved, according to the estimates.

The death toll in New York City, the nation’s epicenter, may have stayed below 1,000.

These are only estimates. It's impossible to know for certain the exact number of people who would have died.

But they are based on infectious disease modeling that gauges how social distancing, once it began, slowed the spread of the virus. nyti.ms/2TsgDa3

The modeling shows that as states reopen, outbreaks can easily get out of control unless infections are closely monitored.

And they also show that if officials do wait to impose restrictions — as many did in March — the delay may come at a great cost. nyti.ms/2TsgDa3