The first version of the graph was created at the end of February by the visual-data journalist Rosamund Pearce of The Economist, drawing from a C.D.C. paper titled “Community Mitigation Guidelines to Prevent Pandemic Influenza.”
It shows two curves for the epidemic over time: A steep peak, if no protective measures are taken, and a flatter slope if people wash their hands, limit travel and practice “social distancing” techniques.
A few days after seeing the Economist infographic, Drew Harris, a population health analyst at Thomas Jefferson University in Philadelphia, added a crucial component: a dotted line indicating the capacity of the health care system to care for people with the virus. He posted it on Twitter and LinkedIn, in which it quickly took off.
“Now I know what going viral means,” Dr. Harris told our colleague Siobhan Roberts.
Flattening the curve with mitigation “reduces the number of cases that are active at any given time, which in turn gives doctors, hospitals, police, schools and vaccine manufacturers time to prepare and respond, without becoming overwhelmed,” he said.
Dr. Harris added: “Some commentators have argued for getting the outbreak over with quickly. That is a recipe for panic, unnecessary suffering and death. Slowing and spreading out the tidal wave of cases will save lives. Flattening the curve keeps society going.”
That’s it for this briefing. See you next time.
To Mark Josephson and Eleanor Stanford for the break from the news. Adam Pasick, on the Briefings team, wrote today’s Back Story. You can reach the team at firstname.lastname@example.org.
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