At the End of Everything by Marieke Nijkamp 

The Hope Juvenile Treatment Center is ironically named. No one has hope for the delinquent teenagers who have been exiled there; the world barely acknowledges that they exist. Then the guards at Hope start acting strange. And one day…they don’t show up. But when the teens band together to make a break from the facility, they encounter soldiers outside the gates. There’s a rapidly spreading infectious disease outside, and no one can leave their houses or travel without a permit. Which means that they’re stuck at Hope. And this time, no one is watching out for them at all.

As supplies quickly dwindle and a deadly plague tears through their ranks, the group has to decide whom among them they can trust and figure out how they can survive in a world that has never wanted them in the first place