The Rage virus is a fictional virus appearing in the 2002 film 28 Days Later directed by Danny Boyle and in the 2007 film 28 Weeks Later directed by Juan Carlos Fresnadillo. It also appears in the graphic novel 28 Days Later: The Aftermath.
In the graphic novel 28 Days Later: The Aftermath, two Cambridge University scientists named Clive and Warren were trying to isolate the specific neurochemicals that cause anger and excessive aggression in humans in order to develop an inhibitor that regulates anger control issues.
Warren decided that it was waste of time to experiment on volunteers from the school for the experiment because Cambridge students obviously didn't have uncontrollable rage. So he manages to get a contact at a police station to give him a violent criminal as a test subject. There was a problem with the delivery system. The injections were too diluted so Warren increased the dosage. However, the inhibitor still had no effect and when the test subject was about to attack Warren and Clive, Warren was forced to kill him. He then immediately decided they would experiment on chimpanzees, as Clive had been suggesting.
As Warren and Clive were burying the criminal, Clive sneezed - giving Warren an idea. They had known that delivering widespread with a pill wouldn't do, neither would an aerosol. He decided that they should use a contagion as a delivery system. He located a certain genome in a strain of the Ebola virus. Using this new delivery system, the two exposed a chimpanzee to the inhibitor. However, the inhibitor mutated. In the chimpanzee, it had the opposite effect of what is was supposed to do. That is, it caused the chimpanzee to be full of uncontrollable rage. Warren had "created a rage virus."
Clive was so disgusted by this that he quit. He later informed an animal rights eco-terrorist organization about the experimenting on animals and then shot himself. A group of those eco-terrorist would later brake into the lab and free the infected rage filled chimpanzee. That chimpanzee attacked and infected them and Warren. From them, the rage virus spread throughout the island of Britain.
Rage is used within the storyline of 28 Days Later and the related media as a scientific alternative to the zombie epidemics of various other films and media. The primary difference of Rage being that it does not kill or reanimate those infected, nor do the infected try to eat the uninfected (they bite to attack, not to eat, and the vomiting is a reflex action). Used as a plot device the effect is very similar—creating an army of mindless killers who will stop at nothing to kill any survivors of the epidemic. Unlike most zombies in popular culture, the infected characters do not suffer any loss of motor control and can still move very quickly and climb obstacles. They can also be killed by any normal means or operate systems of access, as seen in 28 Weeks Later.
The virus is sometimes shown as being passed by the carrier vomiting blood in the face of the victim, causing the virus in their blood to enter the victim. The infected bite as they attack, spreading the virus, and any contact with a carrier's bodily fluids will also infect—Don in 28 Weeks Later is infected during a kiss from his wife. The virus seems to affect within ten to twenty seconds after entering the blood although this varies. The virus is shown as one hundred percent communicable and in the currently released films and graphic novel there is no known cure. In supplemental materials on the 28 Days Later DVD, director Danny Boyle mentions using a complete blood transfusion in one of the alternate endings as a potential cure, but the idea was rejected by himself and movie crew due to not being credible.
Danny Boyle has stated that primates are the only animals that can carry the virus (a fact that is further touched upon in the second film in the series).
Upon exposure to Rage, the infected experience violent spasms as the virus rapidly spreads through their body while ruptured capillaries within their eyes result in both their irises and sclera turning blood red. Internal hemorrhaging of the digestive canal leads to the infected vomiting or drooling copious amounts of infected blood and they scream incoherently when attacking. When they attack the non-infected, they sometimes tackle them and vomit infected blood upon them, causing them to became infected. They may also hit and bite their victims to death.
The Rage virus does not directly cause the death of its host, but because the Infected are solely focused on infecting or killing the non-Infected, they do not eat and eventually die of starvation. Since the Infected act with no regard for self-preservation, they will not act to evade mortal danger, such as fire or bullets.
The Infected will disregard each other and only attack those who do not show symptoms of infection. This is similar to the classic George A. Romero-style zombies, who attack only the living. As a plot device, this allows for huge hordes of the Infected to hunt down a few lone survivors, and allows the virus to spread at an exponential rate through any group of people. In 28 Days Later: The Aftermath, a character wonders how the Infected are able to track non-Infected down and know not to attack each other. After seeing them sniff the air, he concludes that they are attracted by the smells of the non-Infected or maybe just able to smell something other than their own rotten flesh. Disease, anxiety, even rage affects the way people smell. In addition, the Infected have a very pungent odor. Even though the survivors hadn't bathed in weeks, they were still saturated with deodorants and shampoos. The Infecteds' sense of smell is how they find non-Infected.
Though not widely covered in the films, it is obvious that at least some Infected retain a measure of intelligence. This is probably due to the fact that they are not re-animated corpses but living people consumed with rage. There are only four cases within the films that prove this: the infected boy in the diner who shouts, "I hate you!" at Jim (however, this may simply be the soundtrack for the scene being louder than others, as a number of other Infected attacks have similar cries in the background), and infected soldier Mailer who acts like he is injured and needs help in order to lure Jim close enough to attack. Also, when Jim frees Mailer, Mailer ran into the mansion in an attempt to kill the soldiers instead of trying to kill Jim, though this could have been because Jim was on a wall high above Mailer. When Mailer tried to find a different route through the mansion to find Jim, he instead came upon the soldiers. Also, when the group fled from the Infected in a cab in the underground road tunnel, the Infected stopped giving chase, knowing that they were not fast enough to catch up.
Don, the main infected character of the second film, appears to retain the most intelligence, or at least the most control over his actions. Examples of this include Don having a flashback of happy memories with his family, Don's ability to use objects as melee weapons, and attacking Tammy, Andy, and Scarlett from the darkness. Also, unlike other Infected, Don showed a sense of self-preservation. He followed the group around, but never attacked, knowing that he would be shot by Doyle. He also hid when District 1 was firebombed, as well as hiding from the chemical gas attack on the city, avoiding death twice.
One other example, though very brief, is how Don moves within the darkness of the subway; he is vaguely detected by the night vision scope on Scarlett’s rifle, seen walking cautiously while Scarlett calls out for Tammy and Andy. This contrasts with how those infected with Rage move with frequent bursts of speed accompanied by vocalizations.
It should be noted that Don has been infected by his wife, who was a carrier of the Rage virus, rather than an Infected herself. A direct connection to this fact hasn't been mentioned but should be taken into consideration.
28 Weeks Later explores the discovery that there are certain people who will not display any symptoms of the virus except for partially red sclera. The film also suggests that a sign of immunity is heterochromia. These people are classified as "asymptomatic carriers." The person will not become uncontrollably violent like other Infected, and they retain their normal personality. The person is not immune to the virus, however, just the symptoms, and the person can spread the virus as easily as any other Infected (such as saliva contact) in a manner similar to the real-life case of Typhoid Mary.