The Death House — Sarah Pinborough

Lord of the Flies meets Never Let Me Go in this “moving and totally involving” (Stephen King) dystopian thriller from the internationally best-selling author of Behind Her Eyes

Toby's life was perfectly normal . . . until it was unraveled by something as simple as a blood test.

Taken from his family, Toby now lives in the Death House; an out-of-time existence far from the modern world, where he, and the others who live there, are studied by Matron and her team of nurses. They're looking for any sign of sickness. Any sign of their wards changing. Any sign that it's time to take them to the sanatorium.
 
No one returns from the sanatorium.

Living in his memories of the past, Toby spends his days fighting his fear. But then a new arrival in the house shatters the fragile peace, and everything changes. Because everybody dies. It's how you choose to live that counts.