3 Hours Till Dead (2016)

An AWOL soldier with PTSD goes into hiding. Along with his brother and a few friends they retreat into a rural farm area unaware that the outside world has stopped functioning. On their way back to civilization, his brother is attacked and bitten by an infected farmer. The brother quickly turns into a rabid animal and lives for exactly three hours. Realizing that they are in grave danger, they head back to the forest trying to outlive the legions of the infected.