Yep, preach you've got it figured out. It's like in TWD, much of the time the central characters are in more danger from the uninfected than from the infected.

I appreciate your contribution. Thanks.
Put a muzzle on Tits Malone, PI

I'll definitely have to track down the story and read it.
But honestly, my favorite parts of the movie are the human conflicts. With danger literally right outside their door, these people start turning on each other. They want someone to blame for their troubles. That alone is incredibly scary. Instead of coming together, they tear each other apart. The movie does a good job with showcasing the descent into madness.
Apart from that, I love the atmosphere. There is always this sense of dread looming over almost every scene, and it never lets up until the credits roll.
So many stories, so little time.