Basically in the book, the “vampires” are just what the survivors mutated into due to the plague. The protagonist stayed normal though because he was immune to it.
In the past vampires were legends to humans. Due to his hunting them, the protagonist becomes a “legend” in reverse as it were. Basically he’s the guy the vampires fear before they go to sleep, just like humans once feared vampires.
Typically I like these stereotypes...
Vampire: As intelligent as they were as a human. Grow in power as they age, so the older they are, the more intelligent/stronger/etc. they are. (Barring decadence or sloppy arrogance) Drink blood to survive and die from sunlight. Stakes work, but they have to be left in unless you cut off the head and burn the body.
Though I've liked movies that have used this concept, I've never really liked the idea of the mindless vampires that die like hordes of lemmings. Fighting just one vampire should be really hard to do for a human.
Zombie: Typically slow and stupid. Though I can accept the idea of some of them maintaining “memories” or their past life, or even “training” them to a limited degree. They eat living flesh. All of it. (But okay they can go for the brain first)
Speed for a zombie seems like a really unfair advantage, but I can see where they could start off fast when they’re just raised, but after time has passed, rot would take its toll and they’d get slower.