If you could play out some worst-case scenarios based on what has happened since 2010, here is the outcome:

Large numbers of healthy young adults in industrialized countries die, and even more of them are sickened. The World Health Organization reacts with caution about labeling this as an epidemic and outlines a path to control. Almost no one knows the virus, and no one knows how it got into their bodies.

The takeaway from this imagined scenario is that the impact on the health sector of the newly identified coronavirus would be the worst. Almost nobody would have any idea how the virus gets into the body. And in contrast to many other infectious diseases, it could take quite a while for the researchers to figure out what caused the illness to develop into a pandemic that poses health risk to all of us.

The cost of such an outcome is another concern — almost no one would be tested and none would have health insurance. But the possibility of an epidemic was the most important concern, researchers concluded.

Why did the researchers choose this timeframe and in what environment?

“All over the world in 2010, it was the middle of the recession,” researcher Chris Loder, a global health epidemiologist at the World Health Organization in Geneva, told the BBC. “We don’t get global epidemics during good times.”

(For more on what we know, and what we still don’t know, about the novel coronavirus, read this.)

What exactly do they mean by “infections”?

Outbreaks of human infections have been recognized for many years — disease is spread through body fluids such as semen, blood, saliva, or saliva of people who are sick, and that bodily fluids can be from medical or environmental exposure, according to the Centers for Disease Control and Prevention. The WHO reports that the earliest outbreak, dating to the 1940s, was “an adverse response to a conventional peanut allergy in the U.S.”

There have been infection epidemics, such as those identified in 1918, but with the exception of the 1918-1919 Russian influenza pandemic, most outbreaks were limited and do not pose a global threat, according to the WHO.

While researchers may have little idea of how the coronavirus will behave, they are more certain about the human health impact of a generic “non-contagious” disease, which would be the worst to occur if the novel coronavirus were to turn into a pandemic, Loder said. “I would expect more people to get infected if you don’t have a vaccine,” he told the BBC.

What have researchers found so far?

Researchers believe that the novel coronavirus may belong to a family of viruses that are found in North America and in South America, according to the WHO. The viruses have been found in influenza cases and in respiratory tract infections.

But they still don’t know how the viruses spread from person to person.

“Our view is that the virus was probably circulating in the environment before being detected in people,” Loder told the BBC. The WHO is following up on reports of coronavirus infections, and is also working with biomedical and health ministries around the world to prepare for an outbreak.