Ancestor (Ancestry, #2) by Heidi Loney

Calla Ryan, has survived the raids of infected and the scientific experiments. The infected have all but died out, but the virus has now spread to birds and wildlife, threatening food-stores and the safety of the village. When mad scientist Dieter Baxman locates Calla, living with the Mohawk people in their northern village, she must run for her life.

Calla discovers that her ancestry is complicated, beginning with a mysterious Mohawk maiden and through several generations up until the 22nd century. Calla harnesses a mysterious power, and she begins to realise, she is not the only one.