Sam stared. Pierce was still looking his way, but after a moment the man turned and gazed out over the cornfields again, first toward the barn, and then north, in the direction of downtown Ashland and the suburb—and presumably most of the active stations. The direction from which the military response would show up, hopefully anytime now, maybe as a mass of headlights streaming down every country road for miles around.

“I’ll take it from the beginning,” Pierce said. “It starts with a disease. An extremely nasty one called neocortical malaria. It works like other kinds of malaria: mosquitos spread it from host to host. In this case, the disease seems to favor certain species of tropical birds—and sometimes people.”

Pierce turned his back to the railing and leaned against it. Sam and Dani kept their eyes on the barn—and the still-empty horizon to the north.

“I’m sure you know about regular malaria,” Pierce said. “It’s caused by a parasite, and it’s one of the worst diseases in the world. It kills millions of people every year. Compared to that, neocortical malaria is almost unheard-of. It’s never infected nearly that many. It hardly ever infects people at all, because the parasite doesn’t live long inside the mosquito; usually it dies before the mosquito can go from one host to another—unless the hosts are very close together, like birds in a nesting colony. That’s the good news. The bad news is what happens to the unlucky people who do get infected. The symptoms of neocortical malaria are nothing like the other forms of the disease. Not even close.”

“What are they like?” Dani asked.

Pierce was quiet for a long moment. “Like rabies,” he said at last. “Late-stage rabies, the way you see it in a dog. It renders the victim mindless, aggressive, violent, physically erratic. The parasite affects rage-impulse centers in the brain, to the point that its victims will actively try to kill other people. And they can.”

Sam didn’t picture a rabid dog. He didn’t have to. He pictured the baboon in Station 9, bleeding from the eyes and nose, tearing apart the ruins of that place.