The Virus Gauge is a system used in Resident Evil Outbreak and Resident Evil Outbreak File #2 to determine how long a player may spend on a level. Using a percentage system from 0-100%, the player has until the latter to finish the level. If the gauge reaches 100%, the game ends without completion. The only exception to this is Online Mode, where a player will instead become a Zombie and be able to attack their friends.
The rate at which the player reaches Game Over is based on five factors. Firstly, each playable character has their own default rate of infection, measured in percentage points per minute. For example, the character "Tony" was an infection rate of 2.03% per minute, giving players 49 minutes before Game Over should they be unaffected by anything else. The second factor is injury, with an attack by enemies such as Zombies, or suffering from the gas in "Desperate Times", contributing to the Gauge. The fourth is recovery items, with Herbs; Sprays and Antiviruses temporarily halting the gauge, giving the player more time. The fifth factor is unique to Jim-type characters, who have the ability to play dead to avoid enemy attacks, which causes an acceleration of the gauge for as long as they are on the ground.