In the ending "news dialog" there's something in there about a mutated meningitis strain, I'm guessing it'd be viral meningitis. But it all hearkens back to what I was saying this summer after the movie came out. What is "lethal enough"? The flu is potentially lethal, hell, a cold is under the right (although narrow) circumstances. And, yeah, not sure what the guy with the gimped leg was doing to turn away the zombies since Segen's amputated hand wasn't helping her any.
As already mentioned, limping could be due to a bad infection. An infection that bad, could smell like "turned meat".
Also, a limp could be early signs of Polio or MS or Muscular Dystrophy.
One Day I hope to be the Man my Cat thinks I am
Where are we going? And why are we in this Handbasket?