Name that Sci Fi

I have been racking my brain for the title of a sci fi film I saw, where in the end, infected members of society (can't remember if it was zombie or epidemic), were captured by the government, then used as weapons of mass destruction on enemy lines. They were air dropped from planes in metal containers, and as soon as they reached the ground, broke out and ran into the war fields. The main character was a guy, and the last image was him running into a war scene. Ring a bell to anyone? It has been driving me nuts!