The Anthroid Virus is a biogenetically engineered virus, originally designed by GeneTech Solutions in 21XX.
Originally meant to satisfy a market niche of wealthy furries, the Anthroid Virus was meant to induce a transformation from a human into an anthropomorphic furry, based either on a predetermined template or a random selection.
The virus, as a product, has great success initially, but security and random mutations lead to it becoming a planet and system wide pandemic that infected large portions of the population, transforming them into anthropomorphic animals of various forms.
The corporate response of GeneTech Solutions was to deny any allegations of a pandemic existing, as well as initial attempts to kill victims of the pandemic version of the Anthroid Virus, while suing others for breach of copyright. Other corporations then used the pandemic to destroy the company and buy up its patents. There were attempts to create a vaccine against the virus, but corporate greed saw this vaccine sold at horrendous prices, so only the higher ups in the various corporate power structures could afford it.
As the Anthroid Pandemic ran its course, only about ten percent of the population were either immune or could afford the vaccine, leaving 90 percent transformed into various forms of anthro furries.