Rabies virus is a neurotropic virus that causes rabies in humans and animals. Rabies transmission can occur through the saliva of animals and less commonly through contact with human saliva. Rabies virus, like many rhabdoviruses, has an extremely wide host range. In the wild it has been found infecting many mammalian species, while in the laboratory it has been found that birds can be infected, as well as cell cultures from mammals, birds, reptiles and in
TEM micrograph with numerous rabies virions (small dark-grey rod-like particles) and Negri bodies (the larger pathognomonic cellular inclusions of rabies infection)
Virus classification
Group:
Group V ((−)ssRNA)
Order:
Mononegavirales
Family:
Rhabdoviridae
Genus:
Lyssavirus
Species:
Rabies lyssavirus
The rabies virus has a cylindrical morphology and is the type species of the Lyssavirus genus of the Rhabdoviridae family. These viruses are enveloped and have a single stranded RNA genome with negative-sense. The genetic information is packaged as a ribonucleoprotein complex in which RNA is tightly bound by the viral nucleoprotein. The RNA genome of the virus encodes five genes whose order is highly conserved. These genes code for nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G) and the viral RNA polymerase (L).The complete genome sequences range from 11,615 to 11,966 nt in length.[3]
All transcription and replication events take place in the cytoplasm inside a specialized “virus factory”, the Negri body (named after Adelchi Negri[4]). These are 2–10 µm in diameter and are typical for a rabies infection and thus have been used as definite histological proof of such infection.