Positive Viruses were first introduced in the Series V episode "Quarantine" and revisited in the "Back in the Red" trilogy of Series VIII, and in the novel Last Human.
Series V[]
Kryten finds the positive viruses on Lanstrom's planet
The positive viruses were discovered and isolated by Dr. Hildegard Lanstrom who postulated that there were negative viruses (which deteriorated the infected) and positive viruses (which made the infected feel better), the following are known:
- Reverse Flu
- Inspiration (white tube, Latin designation unknown)
- Charisma (green tube, gnotus venustas)
- Sexual Magnetism (red tube, delecto quislibet)
- Luck (blue tube, Felicitus Populi)
Reverse Flu is a basic-level positive virus, which gives the infected a feeling of well-being and happiness even when the infected has had a tough time, where she believed that 20th century DJ's were constant "sufferers".
Under the influence of the luck virus, Dave Lister temporarily becomes the luckiest man alive
The Luck virus was a virus that many contract for short periods at some point in their lives, which allows the infected to do things which are considered almost impossible fairly easy. Allowing Dave Lister to pick four of a kind from a pack of unmarked cards, punch in a door lock code for Bay 47 where the chances of punching in the correct combination were "billions to one" (also the code to unlock his wrist restraint and his cell) just by using whatever combination he felt like, and luckily stumbling on all the components to cure Arnold Rimmer of the Holo Virus (referred to by Dr. Lanstrom simply as psi-virus Latin name). ("Quarantine", Series V)
Series VIII[]
Years later, the recently nanobot-resurrected Rimmer found the sexual magnetism virus in the wreckage of the crashed Starbug, and used it to have sex with all the female officers of Red Dwarf, including Doc Newton. The Sexual Magnetism virus makes the infected irresistible to the opposite sex or seemingly, given sexual orientation, the same sex, where they have an uncontrollable desire to make love to the infected, even if it is Arnold Rimmer (the last one any would want to be seduced by), the only known anti-virus is the Luck Virus, which was discovered by accident by Dave Lister when Kristine Kochanski was overcome by the effects of the Sexual Magnetism virus. ("Back in the Red Part I" and "II", Series VIII)
When Lister poured the entire tube of the virus on Rimmer when they were first sentenced to The Tank (as revenge since Rimmer had betrayed the others), the nearby convicts looked at Rimmer in a disturbing way... ("Back in the Red Part III)"
Novels[]
In the novel Last Human, when the current Starbug crew of Kryten, Rimmer, the Cat and Kochanski are trying to find the missing Lister, Kryten speculates that the Luck Virus essentially grants people mental powers, prompting Rimmer to suggest that they find Lister by each taking the luck virus and then writing down the random coordinates for where they think Lister will be, reasoning that the virus will ensure they all write the same correct coordinates. Having identified the coordinates as being too far away for them to reach before the planet is sucked into a black hole, the Cat uses the luck virus to devise a hyperdrive and a suitable power source to get them there in time to save Lister.