The updates were coming into the situation room thick and fast – and the news was not good. The virus was spreading.

The former deputy director of the CIA took off her glasses, rubbed her eyes, and addressed the panel.

“We also have to consider that terrorists could take advantage of this situation,” she said. “We’re looking at the possibility of famine. There is the potential for outbreaks of secondary diseases.”

One of her aides lent forward, and handed her a note. She read it quickly, and continued: “I have an update from my staff. I’ve been told that several governments have fallen, and others are teetering.”

If it sounds like a scene from a disaster film, the organisers would be pleased: that was their intention. On Friday a panel of 15 high-powered international figures gathered in the ballroom of a New York hotel to “game” a scenario in which a pandemic is raging across the world, killing millions.

It’s not at all far-fetched.

“I fully expect that we will be confronted by a fast-moving global pandemic,” said Dr Mike Ryan, executive director of the World Health Organisation (WHO) health emergencies programme.