Infected

Infected is a custom game mode in Call of Duty: Modern Warfare 3 started as a private match game mode, and was released to the online community playlist on February 5, 2012.

Gameplay
The game starts with all players being survivors. In the upper left hand corner of the screen, there is a timer that starts with 8 seconds counting down to the infected. After 8 seconds, one player is randomly chosen to be infected. The surviving players must hide or survive from the infected. The survivors are the players who are not infected, hence the name "survivors". The survivors spawn with an unknown weapon (depending on what the custom settings are) and must survive by killing the infected or hiding. 100 points are given to survivors every time a survivor is infected. The name given with the points is "Survivor". The round ends when the last survivor is killed/infected and the new round will start pending on a new player to be infected.

Class Loadouts
Survivors Loadouts

Most Common
 * Primary Weapon: Striker (Extended Mags w/ Damage Proficiency)
 * Secondary Weapon: Five Seven (Akimbo)
 * Equipment: Claymore and Smoke
 * Perks: Sleight of Hand Pro, Quickdraw Pro, and Steady Aim Pro

2nd Most Common
 * Primary Weapon: PP90M1 (Extended Mags w/ Kick Proficiency)
 * Secondary Weapon: Five Seven (Akimbo)
 * Equipment: Claymore and Smoke
 * Perks: Sleight of Hand Pro, Quickdraw Pro, and Steady Aim Pro

Least Common
 * Primary Weapon: RSASS (Extended Mags w/ Kick Proficiency)
 * Secondary Weapon: Five Seven (Akimbo)
 * Equipment: Claymore and Smoke
 * Perks: Sleight of Hand Pro, Quickdraw Pro, and Steady Aim Pro
 * Bonus Perk: Scavenger Pro

Infected Loadouts

Infected
 * Primary Weapon: USP .45 (NO AMMO) (Tactical Knife)
 * Equipment: Tactical Insertion
 * Perks: Extreme Conditioning Pro and Quickdraw Pro
 * Bonus Perk: Lightweight
 * Death Streak: Juiced

Initial Infected start off with the same loadout as the survivors with slight tweaks. The initial infected will have a Throwing Knife and Tactical Insertion in their equipment slots. In addition the Initial Infected will have bonus perks Extreme Conditioning Pro and Lightweight. The initial infected will also have the Deathstreak Hollow Points. After the initial infected gets that first kill, the load out will change to a regular infected loadout.

Trivia

 * If the primary and secondary weapons are not selected, the infected have a USP .45 Tactical Knife with no ammo.
 * Infected players do not have specific models and will appear as human soldiers.
 * If the player gets Juggernaut on, infected players will show a unique Juggernaut armor, with a black finish, instead of the whitish armor.
 * Just like Drop Zone, a M.O.A.B. can be achieved despite killstreaks being disabled.