The zombies in Max Brooks' book "The Zombie Survival Guide" and the follow-up novel "World War Z" are people who have been infected with the Solanum virus. They are slow-moving creatures that seem to possess a mysterious sixth sense and stop at nothing to spread the disease via biting and/or scratching living humans. The zombies from the books adhere to the traditional "slow" zombies
While slow, they are extremely dangerous in large groups and can easily overwhelm survivors or corner them. Damage to the body will do very little to slow them down and damage to the brain is typically the surefire method of killing them
Movie
In startling contrast to the novel, the zombies in the film adaptation of World War Z are depicted as the "fast" type of zombies, capable of running towards their would-be victims with ferocity. The zombies appear to have behavior heavily based on that of animals, hence the opening credits of the film which shows various animal species and their habits. For example, they are able to climb atop of one another to form a "pillar" or "wall" of zombies, allowing them to cross high walls, a characteristic taken from ants. Some zombies can lunge at humans, similar to tigers or lions. The zombies also behave like viruses themselves, as their only interest is in spreading the infection and seem to have no real interest in consuming their prey; once they manage to land a bite on a victim, they quickly lose interest in that victim and cease their attack to immediately chase after another uninfected person. While capable of grabbing their victims, they are more dependent on their jaws, snapping away once a target has been sighted
When a human is infected, it is a matter of seconds before they turn. The pathogen responsible for zombification is one of the fastest recorded infections observed with people transforming in as little as 12 seconds, though it is implied that the transformation time can take few minutes as mentioned by a soldier in South Korea. During that time, the person writhes and convulses violently on the ground, contorting and snapping their body in many directions in an uncomfortable manner before finally standing up. Humans who have recently turned do not look too different from while they were alive. However, their eyes become blurry and black veins appear all over their face and body. After some time, they degrade and appear more like typical zombies with decaying flesh and hair loss, though they are still able to move quite fast
The zombies are driven to infect any human they see on sight and are attracted to any loud or man-made noises; such as a car engine or a person's voice. When not attacking they enter a dormant state; listlessly standing around awaiting stimulus. The zombies secrete a black tar-like substance from their mouths. The ooze is surmised to be loaded with the virus and can cause an infection by being splashed into the mouth or eyes, though it can be treated by cleaning the ooze immediately
