Tag, you’re bitten, and ten seconds later (for the majority) you’re a brainless, undead flesh-munching zombie. Surging faster than a mutated strain of H1N1, this rabid virus impacts everyone in “World War Z”. The scene opens as a Philly commute turns into outrun, outgun or outmaneuver a steadily increasing mob of bloodied, carnivorous faces that chop anything that has a thumping heart.

As Gerry Lane (Brad Pitt), a retired United Nations investigator, and his family scramble for safety, the reluctant recruit receives a summons to help his country. Quickly a no-win extortive proposition looms – go search for the origin of this disease or your family becomes nonessential on board a rescue carrier in the tropics.

Dubbed “World War Z,” the battles have been explicitly subdued for PG-13 summer audiences. Spectacle substitutes for hemorrhaging hemoglobin. The title implicates nation against nation, however, all countries apparently courtesy of jet-setting have nearly equal infestations.

Forced to accent imagination not gore, the screenwriter army hailing from “Lost,” “Babylon Five,” and “Buffy” substitute swift suspenseful scenes. A night of shadowy corridors and flickering lights at a dilapidated Newark, N.J. high-rise apartment unleashes one of those creepy-crawly skin moments (though not nearly as bad as my own scratching and a friend’s shifting of her sandal feet nervously during “Arachnophobia” ). Survival comes by rooftop rescue, but persuasion will send the once retired agent globetrotting to an eerie abandoned base in Korea, a walled city in Israel (soon overrun by wall-climbing, roach-like zombies), and multiple heart-jarring, stealth shattering footsteps at the partially infested World Health Organization research facility in Wales.

Director Mark (“Quantum of Solace,” “Monsters Ball”) Forster excels shifting the epic, worldwide feast into more intimate confinement, where a vaccine goal requires strategy to exploit a perceived flesh consuming vulnerability. Forster resonates on an audio dimension, accenting creaking doors, crunching glass, and a stray bottle of Pepsi clashing against the vending machine.

Most of the buzzed production difficulties ( personnel changes and straying from the source novel) stay camouflaged by the “Run, Brad, Run” action. Still, “Z” seems an overall disaster genre (yea, with all the disappearing characters) sauted around a “Contagion,” “Andromeda Strain,” and “Quarantine” package.

“Z” has the requisite big screen awesomely cool visuals, yet, after bowing down to so many profit maximizing filmmaking committees, I ponder how many “Zombieland,” “28 Days Later” and “Night of’s” could have been green-lighted with a portion of its $200 million dollar-plus budget? They rank in the IMDB top ten “zombie” favorites; I don’t think fans will bestow a high ranking to “Z,” despite impressive scene composition.

Pitt glues the acting, particularly his stirring family bonds loyalties, which maintain essential empathy in repeated encounters of those who are not expendable.