Rhalidovirus of the genus Lyssa causes rabies. Differing nucleocapsid and surface protein patterns have developed based on the animal species and the geographic location of the animal involved. Human Rabies Human rabies is characterized by an acute encephalomyelitis that almost always progresses to coma or death within 10 days of the first symptom. Symptoms may include headache, fever, malaise, and a sense of apprehension. Duration of illness without medical attention once symptoms appear is generally two to six days.
Death is most often due to respiratory failure.
The incubation period is usually two to eight weeks, occasionally as short as five days. There is a lot of variation and onset may be as long as a year depending on the severity and site of the wound and the amount of salvia injected. The closer to nerve sites, and the brain, the shorter the incubation period is thought to be. Rarely, rabies has been reported from airborne exposure in laboratories and caves where large numbers of bats reside. This is preferably done on a clinical specimen of the brain or nerves surrounding hair follicles in the nape of the neck.