@esor
She seems to be trying to find out more about how the Infection exactly spreads. Mainly mutations to the Bodies of the Infected to more easily spread to others, and how the Infection affects the Zombies behaviour.
So far she seems to have found out that:
1. The Virus (if thats what it is) keeps the Zombies blood in a fluid state much, much longer than natural, which would enable it to keep infecting people even a good while after the Zombie is already dead.
2. And in this Chapter, it seems that the Zombies follow a small number of always similar "routes" instead of running around randomly when they can't find prey. For example, the Zombie with the Basecap seems to always go from the truck he's lying on to the entrance of the parking-lot and back.
3. Insects (or cockroaches atleast) seemingly can't be infected by the Virus. Which is good, because as she says, Swarms of Zombie-Mosquitos would be very, very bad.