Europe's Disease, as its name suggests, originated in Europe, but was carried by the wind across the world in 1965. Everyone except for the immune Robert Morgan was infected by the plague, and those who did not join together as a group who recieved treatment, died and returned to life as vampires.
Once a living host is infected with Europe's Disease, they exhibit symptoms such as blindness, and will eventually die from the disease. However, after an unknown length of time, the plague will reanimate the deceased victim's corpse.
Upon reanimation, the infected host will become a mindless, undead cannibal. They will seek out blood to drink, and will be weak and unintelligent creatures. They also possess a strong dislike for the smell of garlic, and cannot stand sunlight or their reflection in mirrors.
It is shown that if a human host is bitten and infected by a bat carrying Europe's Disease, as the form of the plague introduced into the human's bloodstream will have already been filtered and weakened by the bat's immune system, this form of the disease will act as a vaccine against Europe's Disease.
There is also a serum that, when injected into an infected host, will temporarily hold the disease at bay until it wears off.
- The fact that Europe's Disease originated in Europe may be a reference to the fact that vampire myths and legends originated in Europe. It is also possible that in the Last Man on Earth universe, the plague broke out in Europe in the 17th century, and those who were infected by the plague and turned into vampires were incorporated into European mythology as the traditional vampire.