The Ripper Virus, also known as the Ripper Compound, was a chemical compound created by Dr. Wes Maxfield to turn Vampires into Augustine Vampires. It was created through genetic alteration, biochemical manipulation and blood-conditioning for the purpose of transforming vampires into cannibalistic, anti-vampire rippers that prey solely upon their own kind, from which it received its infamous moniker. Its prototype was modified vampire blood known as Augustine Blood, which was used to turn Jesse into an Augustine Vampire. It had been used on Damon Salvatore, with Jesse being the test subject prior to him until Jesse was killed by Elena to save Damon's life.
Damon, with help from his friend Enzo was for the most part able to control the Ripper urges by feeding on vampire blood every eight hours since any longer will result in him becoming rabid. The Ripper Virus/Ripper Compound was most recently injected into Elena Gilbert after being enhanced with werewolf toxin, making her more rabid and deadly than even Damon. With both Damon and Elena now cured of the virus, the Ripper Virus has been rendered officially extinct.