"Meaning I didn't need to cut off your arm." He was staring at his knees. "Somehow, your body either neutralized or wasn't affected by the virus," he continued, frowning thoughtfully. "...Somehow..."

He picked his head up abruptly and squinted, looking at Jake again.

"Now that I think of it, how...? We'd been moving for too long, your blood would have circulated through your body, carrying the virus along with it, at least once by the time I removed the source. But you're alive, and cognizant." He tapped the side of his glasses, no longer looking at Jake despite staring forward as though he were.