"Lyssa" comes from a Greek word meaning "frenzy". It is a genus of viruses in the Rhabdovirida family that is characterised by it's ability to drive its victims into a mindless uncontrollable fits of fear and aggression (this includes
humans). The most well known of member of this
virus is Rabies. There are numerous members of this group, such as Mokola
Virus, Duvenhage Virus, Irkut Virus, Khujand Virus, as well as the theorietical virus, Lyssa X.