During certain waves of Zombies they emit a green smoke; if the player is hit by one of these zombies, they become “infected”, and have up to 60 seconds to be decontaminated. Every time the player is hit by a zombie while infected, the player will lose extra time from the counter.
How to become uninfected / decontaminated (Costs 250 Credits)
The Decontamination Zone is a utility in Call of Duty: Advanced Warfare in Exo Zombies, located in Administration. Accessing the Decontamination Zone costs 250 points, and will cleanse the player. It can also cleanse teammates while it is active. Upon being decontaminated, the player will gain invisibility from zombies for a few seconds. The device has a 10 second cooldown time, likely to prevent abuse of the temporary invisibility feature.1 of 1