Bug City Express
Human Meta-Human Vampiric Virus, commonly called HMHVV, is a retrovirus that causes massive physical, psychological, and astral changes in its victims. The virus has been known to cause changes which often resemble abominations that are no longer human and are occasionally not even sentient.
The primary strains create vampires when humans are infected. Other metatypes become goblins, dzoo-noo-qua, wendigos, and banshees. Variant strains can create loup-garou, fomorians, and nosferatu. Only vampires and wendigos can transmit this disease.
The Krieger strain, which has become more common than the original, turns its victims (no matter their metatype) into ghouls. An HMHVV-Krieger infection can be passed on through contact with any bodily fluids from one already infected. However, this strain is also most likely to not destroy the higher brain functions of its victims, leading to the founding of the ghoul nation of Asamando in Africa.