The new plague virus is a fictitious virus that refers to the Fallout Universe.
In the Fallout universe, the New Plague was a devastating, contagious disease in the 2050s causing bleeding, fever, and swelling, leading to U.S. martial law and paranoia, and spurred the creation of the Forced Evolutionary Virus (FEV) by West-Tek, though its origins are debated as potentially Chinese biological warfare or a U.S. government plot for control, with its effects lingering as mutated swamp folk in places like Point Lookout and possibly infecting MacCready's son in Fallout 4.
Symptoms of the new plague: Victims suffered fever, intense sweating, swelling, bloody wounds, and eventually massive hemorrhaging.
Spread of the new plague: Highly contagious through direct contact and droplets, causing widespread panic and border closures.
Government Response to the new plague: The U.S. government used it to justify the National Registry and social control, fostering anti-communist sentiment and linking victims to socialist ideals.
Origins (Theories):
Chinese Weapon: Spies accidentally released it in Denver while fleeing.
U.S. Plot: A fabrication to exert control and justify authoritarian measures.