Rabies

Rabies is a common enough virus to be found in many countries worldwide. It is caused by lyssaviruses, and passed from one mammal to another usually by a bite. It causes inflammation of the brain and a range of other symptoms. It typically takes 1 to 3 months for it to start affecting the victim, but can actually start any time from four days to six years depending on where the bit is, and the amount of the virus initially contracted by the victim.
It initially starts with a fever and headache before causing the brain inflammation. All other symptoms can be slight to partial including: paralysis, anxiety, insomnia, confusion, agitation, abnormal behaviour, paranoia, terror, and hallucinations. In many cases the victim also becomes hydrophobic (fear of water). The symptoms eventually reach a delirious state, and coma. Two to ten days later the victim dies, and in the later stages there is usually no hope for the victim except to try to settle the patient.
The disease has been noted since roughly 2000 BC in Mesopotamia. In Ancient Greece it was known as Lyssa (a spirit of madness). Many folk remedies are known, including the use of a poultice of cloth & hyena skin, a preparation made from the the skull of a hanged man, or the cutting of the attachment of the tongue. So far, none of these seem to work.
A few scholars seem to link this to cases of lycanthropy and vampirism, and there may be such a link if rabies has mutated, at least by magical means.

Type

Viral