Y’all probably know who John Scalzi is. What you may not know is that he has a prequel of sorts for his new novel Lock In available to read online. It’s worth it.

It was clear this wasn’t the H5N1 variant so we started breaking it down to see what we had. What we had was a virus that had a widely variable but long incubation period—that’s the time between when you get the virus and when you start showing symptoms—but a short latency period, meaning the time between when you catch the virus and can start spreading it to other people. Long incubation plus short latency means there’s a fairly large window for subclinical infection—people infecting each other before they feel sick themselves.

So that’s what happened here. The Haden’s virus is transmissible by air, which makes it easy to catch. By the time the International Epidemiological Conference winter meeting had adjourned, roughly eighty percent of the thousand or so attendees had been infected. They had been in close contact and breathing in each other’s air the entire three days. And then when they dispersed they traveled back to several hundred points of origin on six separate continents, traveling in airplanes packed with other people. From a virus’ point of view, you couldn’t have asked for a more optimal transmission pattern.

Now, that’s optimal for the virus. It’s not optimal for us. When it came to the Haden’s virus, by the time we knew what we were dealing with, we also knew that it had potentially already spread to millions and possibly billions of people. What we didn’t know was how serious this new virus would be. We had half of New York throwing up in ER rooms, but we didn’t know how long it would take for the virus to resolve itself, and for the body’s own systems to beat it.

We did know we didn’t have a vaccine. The Haden’s virus initially presented like an influenza virus, but when we started looking at it we realized we really were looking at something new, so the sort of antivirals we use for flu—the neuraminidase and M2 inhibitors—weren’t necessarily going to have the same effect on Haden’s.

So no matter what, we were in for a rough time.

Keep reading.