"I'm sorry" [short story]

His veins were bulging from his face and he froze. He let his fingers trail down the side of his face and over his neck, feeling his breathing catch in his throat. He's seen, no, felt this before on patients. 'I've caught it.' He thought to himself, his heart hammering in his chest. He knows what this does to people, he's had so many people either killed or exiled because of it, and their population was decreasing fast because of it.