Virus: "The Krippin Virus" - re-engineered measles virus. Symptoms: Quick death (90% of population), Degeneration (9%), Immune (1%) First off, it's important to note the huge differences between the original novel of I Am Legend, and the Will Smith adaptation. In the novel, the 'vampires' aren't much different from normal people, other than being unable to stay in sunlight. The film is a very rough adaptation, and instead depicts the Infected as being almost superhumanly strong and acting only on primal aggression. In the film, the virus begins as an attempt to cure cancer, which quickly transitions into a lethal strain that kills most of the population and leaves around 9% transformed into the infected and 1% immune. Robert Neville is able to find a cure, but not until after the human race has been decimated.
