(Capcom's primary storyline)
The t-Vaccine's existence dates to at least 2004, when it was used by WilPharma to stop the spread of the virus during a bioterrorist attack in India. This was later revealed to have been orchestrated by Frederic Downing as a method of demonstrating its power to potential buyers on the black market. As a result of their refusal to show their full research data, TerraSave protesters limited its use in the United States. In 2005, the virus was used at the Harvardville Airport. The US Marine Corps succeeded in quarantining the area, and the vaccine was used to treat the infected. Due to the restrictions, however, the vaccine stocks were used up at the airport.