How canceled events and self-quarantines save lives, in one chart

The main uncertainty in the coronavirus outbreak in the United States now is how big it will get, and how fast. The Centers for Disease Control and Prevention’s Nancy Messonnier told reporters on March 9, “many people in the US will at some point, either this year or next, get exposed to this virus.”

According to infectious disease epidemiologist Marc Lipsitch at Harvard, it’s “plausible” that 20 to 60 percent of adults will be infected with Covid-19 disease. So far, 80 percent of cases globally have been mild, but if the case fatality rate is around 1 percent (which several experts say it may be), a scenario is possible of tens or hundreds of thousands of deaths in the US alone.

The main uncertainty in the coronavirus outbreak in the United States now is how big it will get, and how fast. The Centers for Disease Control and Prevention’s Nancy Messonnier told reporters on March 9, “many people in the US will at some point, either this year or next, get exposed to this virus.”

According to infectious disease epidemiologist Marc Lipsitch at Harvard, it’s “plausible” that 20 to 60 percent of adults will be infected with Covid-19 disease. So far, 80 percent of cases globally have been mild, but if the case fatality rate is around 1 percent (which several experts say it may be), a scenario is possible of tens or hundreds of thousands of deaths in the US alone.

Yet the speed at which the outbreak plays out matters hugely for its consequences. What epidemiologists fear most is the health care system becoming overwhelmed by a sudden explosion of illness that requires more people to be hospitalized than it can handle. In that scenario, more people will die because there won’t be enough hospital beds or ventilators to keep them alive.

A disastrous inundation of hospitals can likely be averted with protective measures we’re now seeing more of — closing schools, canceling mass gatherings, working from home, self-quarantine, self-isolation, avoiding crowds — to keep the virus from spreading fast.

Epidemiologists call this strategy of preventing a huge spike in cases “flattening the curve,” and it looks like this:

“Even if you don’t reduce total cases, slowing down the rate of an epidemic can be critical,” wrote Carl Bergstrom, a biologist at the University of Washington in a Twitter thread praising the graphic, which was first created by the CDC, adapted by consultant Drew Harris, and popularized by the Economist. The chart has since gone viral with the help of the hashtag #FlattenTheCurve.

Flattening the curve means that all the social distancing measures now being deployed in places like Italy and South Korea, and on a smaller scale in places like Seattle and Santa Clara County, California, aren’t so much about preventing illness but rather slowing down the rate at which people get sick.

The CDC advises that people over age 60 and people with chronic medical conditions — the two groups considered most vulnerable to severe pneumonia from Covid-19 — to “avoid crowds as much as possible.”

More :  https://www.vox.com/2020/3/10/21171481/coronavirus-us-cases-quarantine-cancellation