Rabies is an often fatal disease caused by the infection of mammals with rabies virus. In the 21st century it is mainly a disease that affects wild mammals such as foxes and bats, but it is one of the oldest known virus diseases: rabies is a Sanskrit word (rabhas) that dates from 3000 BC, which means "madness" or "rage", and the disease has been known for over 4000 years. Descriptions of rabies can be found in Mesopotamian texts, and the ancient Greeks called it "lyssa" or "lytta", meaning "madness". References to rabies can be found in the Laws of Eshnunna, which date from 2300 BC. Aristotle (384–322 BC) wrote one of the earliest undisputed descriptions of the disease and how it was passed to humans. Celsus, in the first century AD, first recorded the symptom called hydrophobia and suggested that the saliva of infected animals and humans contained a slime or poison – to describe this he invented the word "virus". Rabies does not cause epidemics, but the infection was greatly feared because of its terrible symptoms, which include insanity, hydrophobia and death.
