Lyssavirus

This article is about the rabiform virus. For the hemorrhagic fever-causing virus, see Lassa virus.
Lyssavirus
Colored transmission electron micrograph of Australian bat lyssavirus. The bullet-like objects are the virus, and some of them are budding off from a cell.
Virus classification
Group: Group V ((-)ssRNA)
Order: Mononegavirales
Family: Rhabdoviridae
Genus: Lyssavirus
Type species
Rabies virus
Species

Aravan virus
Australian bat lyssavirus
Bokeloh Bat lyssavirus
Duvenhage virus
European Bat lyssavirus 1
European Bat lyssavirus 2
Irkut virus
Khujand virus
Lagos bat virus
Mokola virus
West Caucasian bat virus
Shimoni bat virus

Lyssavirus (from Lyssa, the Greek goddess of madness, rage, and frenzy) is a genus of viruses belonging to the family Rhabdoviridae, in the order Mononegavirales. This group of RNA viruses includes the rabies virus traditionally associated with the disease.

Virology

Structure

Viruses typically have either helical or cubic symmetry. Lyssaviruses have helical symmetry, so their infectious particles are approximately cylindrical in shape. This is typical of plant-infecting viruses. Human-infecting viruses more commonly have cubic symmetry and take shapes approximating regular polyhedra.

The structure consists of a spiked outer envelope, a middle region consisting of matrix protein M, and an inner ribonucleocapsid complex region, consisting of the genome associated with other proteins.

Genome

Lyssavirus genome consists of a negative-sense, single-stranded RNA molecule that encodes five viral proteins: polymerase L, matrix protein M, phosphoprotein P, nucleoprotein N, and glycoprotein G.

Based on recent phylogenetic evidence, lyssaviruses are categorized into seven major species. In addition, five species recently have been discovered: West Caucasian bat virus, Aravan virus, Khujand virus, Irkut virus and Shimoni bat virus.[1][2] The major species include rabies virus (species 1), Lagos bat virus (species 2), Mokola virus (species 3), Duvenhage virus (species 4), European Bat lyssaviruses type 1 and 2 (species 5 and 6), and Australian bat lyssavirus (species 7).[3]

Based on biological properties of the viruses, these species are further subdivided into phylogroups 1 and 2. Phylogroup 1 includes genotypes 1, 4, 5, 6, and 7, while phylogroup 2 includes genotypes 2 and 3. The nucleocapsid region of lyssavirus is fairly highly conserved from genotype to genotype across both phylogroups; however, experimental data have shown the lyssavirus strains used in vaccinations are only from the first species(i.e. classic rabies).[3]

Epidemiology

Species 1, classic rabies, is prevalent throughout most of the world and can be carried by any warm blooded mammal. The other species (2 through 7) have much less diversity in carriers. Only select hosts can carry each of the viral species. Also, these other species are particular only to a specific geographic area. Bats are known to be an animal vector for all identified lyssavirus species except the Mokola virus.[4]

See also

Footnotes

  1. ↑ Virus Taxonomy: 2013 Release. ictvonline.org
  2. ↑ Kuzmin, I.; Hughes, G.; Botvinkin, A.; Orciari, L.; Rupprecht, C. (2005). "Phylogenetic relationships of Irkut and West Caucasian bat viruses within the genus and suggested quantitative criteria based on the N gene sequence for lyssavirus genotype definition". Virus Research 111 (1): 28–25. doi:10.1016/j.virusres.2005.03.008. PMID 15896400.
  3. ↑ 3.0 3.1 Badrane, H.; Bahloul, C.; Perrin, P.; Tordo, N. (2001). "Evidence of Two Lyssavirus Phylogroups with Distinct Pathogenicity and Immunogenicity". Journal of Virology 75 (7): 3268–3276. doi:10.1128/JVI.75.7.3268-3276.2001. PMC 114120. PMID 11238853.
  4. ↑ WHO Rabnet/CDC Map Production (2008). "Rabies, countries or areas at risk". World Health Organization.

Bibliography

External links

Wikimedia Commons has media related to Lyssavirus.