Rabies, which collectively includes the lyssavirus and all strains of bat lyssviruses, is a collective group of virus strains in the Rhabdoviridae family. In addition to the rabies virus, the genus lyssavirus includes the Australian bat virus, Mokola virus, Duvenhage virus, European bat viruses 1 and 2, ant the Lagos bat virus. Rabies only affects mammals, and does not affect other fauna. In an infected creature, the rabies virus is found only in the nervous tissue or in the saliva of that creature, meaning that transmission occurs primarily through scratches, bites, or through saliva entering an open wound.
Once inside the body, the virus follows a specific course of actions:
- Travels through the muscle tissue to enter nervous tissues.
- Travels up spinal nervous tissue toward brain.
- Once inside brain, begins to multiply rapidly, beginning the distinct and easily recognizable symptoms.
- The onset of encephalitis occurs in the brain, which is followed by a prolonged, painful death.
The incubation period of the virus from initial contraction to the onset of the first symptoms can last anywhere from a few days to a couple of months. This is determined by the amount of rabies virus transmitted by the bite or scratch, the severity and size of the wound, and the location of the wound on the body. While no initial symptoms occur, other than slight pain or itching around the bite or scratch wound, symptoms reminscent of a fever soon follow. An elevated body temperature, coughing and sneezing, headaches, dizziness, confusion, are all common symptoms. As the virus multiplies in the brain, the symptoms become more painful and more sever, with more symptoms like loss of balance, trouble breathing, muscle spasms, and agitation. In humans, hydrophobia and aerophobia are common, as the virus causes severe and painful muscle spasms in the throat, rendering the victim unable to drink water. After the onset of symptoms, death is almost surely imminent.