“Sometimes I do, yes. The patrols would gather up residue and test it for contamination; when the tested matter no longer revealed a danger, the crisis would be over except for mopping up the stragglers.”

“Except for—” Gary jerked away from the girl. “Like us?” he asked flatly.

“Like us,” Oliver nodded. “Latent carriers, Typhoid Marys, apparently immune but spreading the death by merely breathing.”

“That's a hell of a note! Either they shoot us for crossing the bridge, or they shoot us for staying alive over here. What's the damned country coming to?” He jerked his line savagely through the water.

Sally left him to wade nearer the other man.

“May not be that bad at all,” Oliver pointed out mildly, apparently unworried about his future. “Not by the time they get around to us. All depends on the prevailing mood of high brass and the state of medicine on the day the bridges are reopened. If the stragglers can be cleansed and cured by some revolutionary medical means — welcome back to the United States. If not — why then, we're blocking reconstruction.”

“Yeah, fine! I can see me blocking reconstruction. Haven't they got anything to cure us?”

“Who can say? Science makes wonderful strides in some respects and yet stands still in others. We thought the atomic bomb would make the land uninhabitable for thousands of years, yet you can move right back in a short while after an airburst. When I was teaching school there were no known cleansing agents for the likes of you and me — and Sally.”

“What about that stuff I read in the library?”

“Oh, vaccines exist, yes, but they are intended as a preventive measure, not an antidote to be administered a year or more after the poison takes effect.” He was gazing at the point where the sea met the horizon. “Seem to recall there were vaccines for one or two types of toxin of botulism, but antitoxins are useless at this late date. And as for the pneumonic plague! Perhaps, just perhaps, sulfadiazine and streptomycin could help if you were treated immediately.”