Heres a report on the T-Virus:

T-virus

The Tyrant virus, or T-virus, is the main virus used by Umbrella, and is responsible for the creation of most of their BOWs.

According to reports in the game, Dr. James Marcus succeeded in creating the Tyrant virus at the Arklay Management Training Facility on September 19th, 1978[1] through synthesis of the Progenitor virus and leech DNA. Through this synthesis, the photosensitivity of the early Progenitor strain was replaced with pyrosensitivity, a property that can be seen in most of the series' enemies.

The Tyrant virus allegedly operates similarly to most other viruses, but also has the abilities to reanimate dead tissue, to substantially mutate its host, and to infect nearly any tissue in any type of host. It animates dead tissue by killing and replacing any mitochondria in infected cells, and then combining with these cells to produce enough energy for motor and lower brain functions. By doing this, most of the body's systems, such as the circulatory or respiratory systems, are made redundant. However, this process has the drawback of severe necrosis in the host, and produces the distinctive rotted appearance of most BOWs. The mutations are produced when the virus incorporates itself into the host's genetic code and considerably alters it. Creatures with genetic structures different than humans generally show less severe mutations, and usually only increase in size.

As a side effect of the virus' consumption of its host, specifically its digestion of the host's frontal lobes, all hosts suffer from increased aggression. The virus also damages the hypothalamus, which results in a flood of neurotransmitters, enzymes, and hormones which induce a psychopathic rage and hunger in the host.

'Daylight' is the only T-virus vaccine, but must be taken before transformation. The film series presents a preventative vaccine known simply as the 'anti-virus', which must be taken within several hours after the initial infection. In Resident Evil, it is revealed that if the anti-virus is taken too late, the T-virus will cause it to be rejected. Umbrella also attempted to develop several other vaccines; T-vaccine was created by WilPharma, but an employee was selling it, as well as T- and G-virus samples, on the black market to bio-terrorists. 'AT1521' was Umbrella's first official attempt at a vaccine, but the original sample was destroyed. There was also an unnamed vaccine being developed under the Raccoon General Hospital in Resident Evil 3 that was used to save Jill Valentine.

[edit] T-Veronica virus

The T-Veronica virus is the main virus used in Resident Evil Code: Veronica, and is responsible for the mutation of several enemies. There is also a variant strain of the virus named T-Alexia that is a diluted form of the virus created during its period of cryogenesis in its main host, Alexia Ashford.

According to the series timeline, the T-Veronica virus was created by Alexia Ashford through synthesis of the Progenitor virus and the gene of a queen ant that contained an "ancient virus". She administered it to her father, but because the infection was not controlled, he became unstable and mindless. This led her to discover that the mutations could be controlled if slowly absorbed during cryogenesis.

Like the Progenitor and T- viruses, the T-Veronica virus causes rapid mutation, but the infection can be controlled and intelligence can be retained if the virus is absorbed over a long period of time. Alexia Ashford achieved this by remaining in a cryogenic sleep for fifteen years while the virus merged with her at a cellular level. Among the mutations to Alexia caused by the virus were combustible blood and vomit, multiple tentacular muscles, and the ability to exert control over the hive mind of the ants the virus was extracted from.

Though the T-Veronica virus is a useful tool for transhumanism purposes, it is useless as a bio-weapon, as its infection rate is low and it can only be transferred through direct injection. Because she is able to mentally control any organism infected with T-Veronica, Alexia, rather than use the virus as a weapon, planned to use her infected ants to spread the virus around the world by biting and injecting humans and animals with the virus, giving her control of every creature on earth.

[edit] NE-T virus

The NE-T virus is very similar to the T-virus, but was designed specifically for the Tyrant Project.

According to the series timeline, Umbrella required BOWs that were not only stronger, but could understand and complete missions, and due to the nature of the T-virus, all of its BOWs were unable to do this. The project was divided between an American team, led by Birkin, which would work on increasing the BOWs' strength and ability to detect organisms, and a European team that would work on increasing their intelligence. The two teams traded theories and ideas that included the first experiments in directly operating on a subject's brain. The American team succeeded in creating the NE-T virus, along with the T-002, which could follow simple orders such as "Restrain" and "Attack", though its intelligence was insufficient for field operations.

In response to reports of the T-002’s failure, Umbrella renamed the European team's project with the title "Goddess of Vengeance", or "Nemesis", and gave it the new goal of eliminating all anti-Umbrella elements; specifically, the STARS. The European team made a breakthrough with the creation of the NE-α, an organism created from the NE-T virus that affected the host's brain. Further experiments with this strain led to the creation of the T-103, also known as "Mr. X".

[edit] T-Cameron virus

The T-Cameron virus is a hypothetical name for Dr. Cameron's "T" strain, appearing in Biohazard 4D Executor. It was created when Cameron injected herself with an experimental serum, to stop the T-virus from spreading when she was infected. However the serum mutated her body, allowing her the capabilities of massive shapeshifting. While her body was killed, another unforeseen side effect of the virus took place when her body was eaten by insects, her consciousness apparently had been encoded within her cells. Given this, she had become effectively immortal, as long as she had a viable host to transfer any source of her corrupt DNA to remake it into her next body. She used these powers to leap from a cockroach that had consumed trace cells from her corpse to a nearby rat, to a crow outside and from there to a member of the UBCS unit sent to retrieve her investigation. While this last body was destroyed, she had a "backup", which eventually was absorbed by another member of the same unit, allowing her to escape Raccoon.

[edit] T-JCCC203

T-JCCC203 was an experimental T-variant mutagen. It was administered to 63 year old Doug Frost in the abandoned hospital during its Drugs, Inc. ownership. Doug's cancer was destroyed, but the T-virus killed him hours later.

The same chemical was administered to 35 year old Dorothy Lester, whose health came back to her to the point she no longer needed a respirator. However the side effect was an increased metabolism, ultimately leading to T-virus infestation and death after she killed an investigator perusing into the Abandoned Hospital's affairs.

They are not all one Virus but i decided to do all the different forms of the T-Virus