T-Virus

The T-Virus is a fictional virus featured in the Resident Evil multimedia franchise. It served as the primary plot device used to govern the events chronicled in the video game series by Capcom and in the Resident Evil film series by Screen Gems.

As a storytelling tool, the T-Virus is used to explain the origin of how all the characters in a given setting are turned into flesh-eating zombies. In the series, the protagonists must fight up against those infected the T-Virus (the zombies), as well as labor to help those who can be saved through a cure.

Description
The T-Virus is a biochemical weapon developed by the Umbrella Corporation. It was produced and tested at a secret underground facility outside of Raccoon City called the Hive. The virus produced the effect of reanimating dead cell tissue, effecting resurrecting deceased humans and animals. These subjects were not resurrected in the truest sense however, but were little more than shambling shells of their former selves. Possessing no intelligence and perhaps even the vaguest of memories of their past lives, these veritable zombies were driven by a single biological instinct - the need to feed. For reasons that remain unclear, these subjects only fed off the flesh of other living organisms. It has been shown that this was purely an instinctive measure, as these creatures did not require nourishment for function.

The T-Virus has been described as Protean in its application, able to transmit itself through liquid, or through the atmosphere, or through blood transmission. The artificial intelligence governing the Hive's facilities, the Red Queen, described the effects of the T-Virus as thus: "Even in death the human body still is active. Hair and finger nails continue to grow, new cells are produced, and the brain itself holds a small electrical charge that takes months to dissipate. The T-virus provides a massive jolt, both to cellular growth, and to those trace electrical impulses. Put quite simply, it reanimates the body."

When the T-Virus is injected directly into living tissue, the effects were both unexpected and bizarre. It mutated the host subject on a biological level, transforming them into a hideous creature that continued to mutate and evolve. Dubbed a "licker", the mutant's physiology would change and adapt as it continued to feed.

In contrast to the virus itself, the Hive also created an antivirus. It was believed to be successful if administered directly after the transmission of infection. However, the success ratio diminished dramatically the longer a host remained infected.