Kalahari by Jessica Khoury

When an educational safari goes wrong, five teens find themselves stranded in the Kalahari Desert without a guide. It’s up to Sarah, the daughter of zoologists, to keep them alive and lead them to safety, calling on survival know-how from years of growing up in remote and exotic locales. Battling dehydration, starvation and the pangs of first love, she does her best to hold it together, even as their circumstances grow increasingly desperate.

But soon a terrifying encounter makes Sarah question everything she’s ever known about the natural world. A silver lion, as though made of mercury, makes a vicious, unprovoked attack on the group. After a narrow escape, they uncover the chilling truth behind the lion’s silver sheen: a highly contagious and deadly virus that threatens to ravage the entire area—and eliminate life as they know it.