Editing Lyssavirus

{{short description|Genus of viruses}}
{{cs1 config|name-list-style=vanc}}
{{about|the rabiform virus|the hemorrhagic fever-causing virus|Lassa virus}}
{{Use dmy dates|date=April 2017}}
{{Virusbox
| image = CSIRO ScienceImage 1977 Bat Lyssavirus.jpg
| image_alt = Colored transmission electron micrograph of "Australian bat lyssavirus". The bullet-like objects are the virions, and some of them are budding off from a cell.
| image_caption = Colored [[transmission electron micrograph]] of [[Australian bat lyssavirus]]. The bullet-like objects are the virions, and some of them are budding off from a cell.
| taxon = Lyssavirus
| synonyms =
| synonyms_ref =
| subdivision_ranks = Species
| subdivision = [[#Taxonomy|See text]]
}}

'''''Lyssavirus''''' (from the [[Ancient Greek|Greek]] {{lang|el|λύσσα}} ''lyssa''  "rage, fury, rabies" and the [[Latin]] ''[[Virus#Etymology|vīrus]]'')<ref>{{LSJ|lu/ssa^|λύσσα|ref}}.</ref><ref>{{L&S|virus|vīrus|ref}}</ref> is a genus of [[RNA virus]]es in the family ''[[Rhabdoviridae]]'', order ''[[Mononegavirales]]''. Mammals, including humans, can serve as natural [[Host (biology)|host]]s.<ref name=ViralZone>{{cite web|title=Viral Zone|url=http://viralzone.expasy.org/all_by_species/22.html |publisher=[[ExPASy]] |access-date=15 June 2015}}</ref> The genus ''Lyssavirus'' includes the [[causative agent]] ([[rabies virus]]) of [[rabies]].<ref>{{Cite encyclopedia
|title=Virus - Annotated classification
|encyclopedia=Britannica
|url=https://www.britannica.com/science/virus/Annotated-classification
|date=2024-06-18
}}</ref>

==Taxonomy==
The genus contains the following species, listed by scientific name and followed by the exemplar virus of the species:<ref>{{cite web|title=Virus Taxonomy: 2024 Release|url=https://ictv.global/taxonomy|publisher=International Committee on Taxonomy of Viruses|access-date=15 March 2025}}</ref>
{{div col}}
* ''Lyssavirus aravan'', [[Aravan virus]]
* ''Lyssavirus australis'', [[Australian bat lyssavirus]]
* ''Lyssavirus bokeloh'', [[Bokeloh bat lyssavirus]]
* ''Lyssavirus caucasicus'', [[West Caucasian bat virus]]
* ''Lyssavirus duvenhage'', [[Duvenhage virus]]
* ''Lyssavirus formosa'', [[Taiwan bat lyssavirus]]
* ''Lyssavirus gannoruwa'', [[Gannoruwa bat lyssavirus]]
* ''Lyssavirus hamburg'', [[European bat lyssavirus 1]]
* ''Lyssavirus helsinki'', [[European bat lyssavirus 2]]
* ''Lyssavirus ikoma'', [[Ikoma lyssavirus]]
* ''Lyssavirus irkut'', [[Irkut virus]]
* ''Lyssavirus khujand'', [[Khujand virus]]
* ''Lyssavirus kotalahti'', [[Kotalahti bat lyssavirus]]
* ''Lyssavirus lagos'', [[Lagos bat virus]]
* ''Lyssavirus lleida'', [[Lleida bat lyssavirus]]
* ''Lyssavirus mokola'', [[Mokola virus]]
* ''Lyssavirus rabies'', [[Rabies virus]]
* ''Lyssavirus shimoni'', [[Shimoni bat virus]]
{{div col end}}
==Virology==
=== Structure ===
Lyssavirions are enveloped, with bullet shaped geometries. These virions are about 75&nbsp;nm wide and 180&nbsp;nm long.<ref name=ViralZone /> Lyssavirions have helical symmetry, so their infectious particles are approximately cylindrical in shape. This is typical of plant-infecting viruses. Virions of human-infecting viruses more commonly have cubic symmetry and take shapes approximating [[regular polyhedron|regular polyhedra]].{{cn|date=January 2023}}

The structure consists of a spiked outer [[envelope (biology)|envelope]], a middle region consisting of matrix protein M, and an inner [[ribonucleocapsid]] complex region, consisting of the genome associated with other proteins.{{cn|date=January 2023}}

===Genome===
Lyssavirus [[genome]]s consist 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. Genomes are linear, around 11kb in length.<ref name=ViralZone />

Based on recent phylogenetic evidence, lyssaviruses have been categorized into seven major [[species]]. In addition, five more species have recently been discovered: West Caucasian bat virus, Aravan virus, Khujand virus, Irkut virus and Shimoni bat virus.<ref>[http://ictvonline.org/virusTaxonomy.asp Virus Taxonomy: 2013 Release]. ictvonline.org</ref><ref>{{cite journal | vauthors = Kuzmin IV, Hughes GJ, Botvinkin AD, Orciari LA, Rupprecht CE | title = Phylogenetic relationships of Irkut and West Caucasian bat viruses within the Lyssavirus genus and suggested quantitative criteria based on the N gene sequence for lyssavirus genotype definition | journal = Virus Research | volume = 111 | issue = 1 | pages = 28–43 | date = July 2005 | pmid = 15896400 | doi = 10.1016/j.virusres.2005.03.008 | url = https://zenodo.org/record/1259441 }}</ref> The lyssavirus genus can be divided into four [[phylogroup]]s based upon DNA sequence homology. Phylogroup I includes viruses, such as Rabies virus, Duvenhage virus, European bat lyssavirus types 1 and 2, Australian bat lyssavirus, Khujand virus, Bokeloh bat lyssavirus, Irkut virus, and Aravan virus. Phylogroup II contains Lagos bat virus, Mokola virus, and Shimoni bat virus. West Caucasian bat lyssavirus is the only virus that is a part of phylogroup III. Ikoma lyssavirus and Lleida bat lyssavirus are examples in phylogroup IV. West Caucasian bat lyssavirus was classified within its own phylogroup because it is the most divergent lyssavirus that has been discovered.<ref>{{cite journal | vauthors = Gould AR, Kattenbelt JA, Gumley SG, Lunt RA | title = Characterisation of an Australian bat lyssavirus variant isolated from an insectivorous bat | journal = Virus Research | volume = 89 | issue = 1 | pages = 1–28 | date = October 2002 | pmid = 12367747 | doi = 10.1016/s0168-1702(02)00056-4 }}</ref>

{| class="wikitable sortable" style="text-align:center"
|-
! Genus !! Structure || Symmetry !! Capsid !! Genomic arrangement !! Genomic segmentation
|-
|''Lyssavirus''||Bullet-shaped||||Enveloped||Linear||Monopartite
|}

===Evolution===
Phylogenetic studies suggest that the original hosts of these viruses were bats.<ref name=Banyard2011>{{cite journal | vauthors = Banyard AC, Hayman D, Johnson N, McElhinney L, Fooks AR | title = Bats and lyssaviruses | journal = Advances in Virus Research | volume = 79 | pages = 239–289 | year = 2011 | pmid = 21601050 | doi = 10.1016/B978-0-12-387040-7.00012-3 | isbn = 978-0-12-387040-7 }}</ref> However, the recent discovery of lyssavirus sequences from amphibians and reptiles challenges the mammalian origin of lyssaviruses.<ref name="Oberhuber2021">{{cite journal |last1=Oberhuber |first1=Martina |last2=Schopf |first2=Anika |last3=Hennrich |first3=Alexandru Adrian |last4=Santos-Mandujano |first4=Rosalía |last5=Huhn |first5=Anna Gesine |last6=Seitz |first6=Stefan |last7=Riedel |first7=Christiane |last8=Conzelmann |first8=Karl-Klaus |title=Glycoproteins of Predicted Amphibian and Reptile Lyssaviruses Can Mediate Infection of Mammalian and Reptile Cells |journal=Viruses |date=September 2021 |volume=13 |issue=9 |pages=1726 |doi=10.3390/v13091726|pmid=34578307 |pmc=8473393 |doi-access=free }}</ref><ref name="Horie2021">{{cite journal |last1=Horie |first1=Masayuki |last2=Akashi |first2=Hiroshi |last3=Kawata |first3=Masakado |last4=Tomonaga |first4=Keizo |title=Identification of a reptile lyssavirus in Anolis allogus provided novel insights into lyssavirus evolution |journal=Virus Genes |date=1 February 2021 |volume=57 |issue=1 |pages=40–49 |doi=10.1007/s11262-020-01803-y|pmid=33159637 |s2cid=226276694 }}</ref> The greater antigenic diversity of lyssaviruses from [[Africa]] has led to the assumption that Africa was the origin of these viruses. An examination of 153 viruses collected between 1956 and 2015 from various geographic locations has instead suggested a [[Palearctic]] origin (85% likelihood) for these viruses.<ref name=Hayman2016>{{cite journal | vauthors = Hayman DT, Fooks AR, Marston DA, Garcia-R JC | title = The Global Phylogeography of Lyssaviruses - Challenging the 'Out of Africa' Hypothesis | journal = PLOS Neglected Tropical Diseases | volume = 10 | issue = 12 | pages = e0005266 | date = December 2016 | pmid = 28036390 | pmc = 5231386 | doi = 10.1371/journal.pntd.0005266 | doi-access = free }}</ref> Date estimates (95% likelihood) for the most recent common ancestor were very broad – between 3,995 and 166,820 years before present – which suggests there is further work to be done in this area. Although bats evolved in the Palearctic,<ref name=Teeling2005>{{cite journal | vauthors = Teeling EC, Springer MS, Madsen O, Bates P, O'brien SJ, Murphy WJ | title = A molecular phylogeny for bats illuminates biogeography and the fossil record | journal = Science | volume = 307 | issue = 5709 | pages = 580–584 | date = January 2005 | pmid = 15681385 | doi = 10.1126/science.1105113 | s2cid = 25912333 | bibcode = 2005Sci...307..580T }}</ref> their origins antedate that of the lyssaviruses by millions of years, which argues against their co-speciation. The evolution rate in the N gene in the Africa 2 lineage has been estimated to be 3.75×10<sup>−3</sup> substitutions per site per year.<ref name=He2017>{{cite journal | vauthors = He W, Zhang H, Zhang Y, Wang R, Lu S, Ji Y, Liu C, Yuan P, Su S | display-authors = 6 | title = Codon usage bias in the N gene of rabies virus | journal = Infection, Genetics and Evolution | volume = 54 | pages = 458–465 | date = October 2017 | pmid = 28818621 | doi = 10.1016/j.meegid.2017.08.012 }}</ref> This rate is similar to that of other RNA viruses.

==Life cycle==
Viral replication is cytoplasmic. Entry into the host cell is achieved by attachment of the viral G glycoproteins to host receptors, which mediates [[receptor-mediated endocytosis|clathrin-mediated endocytosis]]. Replication follows the negative stranded RNA virus replication model. Negative stranded RNA virus transcription, using [[polymerase stuttering]], is the method of transcription. The virus exits the host cell by budding and by  tubule-guided viral movement.
Wild mammals, especially bats and certain carnivores, serve as natural hosts. Transmission routes are typically via bite wounds.<ref name=ViralZone />

{| class="wikitable sortable" style="text-align:center"
|-
! Genus !! Host details !! Tissue tropism !! Entry details !! Release details !! Replication site !! Assembly site !! Transmission
|-
|''Lyssavirus''||bats, ''[[Crocidura]]'' shrews and certain carnivores||Neurons||Clathrin-mediated endocytosis||Budding||Cytoplasm||Cytoplasm||Bite wounds
|}

==Testing==
As of 2018 the [[direct fluorescent antibody]] (DFA) test is still the gold standard to detect lyssavirus infection. Since the new millennium [[reverse transcription PCR]] (RT-PCR) tests have been developed for rabies but only been used as a confirmatory test. [[Real-time PCR]]-based tests which have higher sensitivity and objective diagnostic thresholds and allow samples to be stored at room temperature have been promising since 2005, but require a real-time PCR machine and skilled workers with experience in molecular diagnostics. In an international evaluation a single [[TaqMan]] LN34 assay could detect Lyssavirus with high sensitivity (99.90%) across the genus and high specificity (99.68%) when compared to the DFA test. It will become the primary post-mortem rabies diagnostic test where possible.<ref>{{cite journal | vauthors = Gigante CM, Dettinger L, Powell JW, Seiders M, Condori RE, Griesser R, Okogi K, Carlos M, Pesko K, Breckenridge M, Simon EM, Chu MY, Davis AD, Brunt SJ, Orciari L, Yager P, Carson WC, Hartloge C, Saliki JT, Sanchez S, Deldari M, Hsieh K, Wadhwa A, Wilkins K, Peredo VY, Rabideau P, Gruhn N, Cadet R, Isloor S, Nath SS, Joseph T, Gao J, Wallace R, Reynolds M, Olson VA, Li Y | display-authors = 6 | title = Multi-site evaluation of the LN34 pan-lyssavirus real-time RT-PCR assay for post-mortem rabies diagnostics | journal = PLOS ONE | volume = 13 | issue = 5 | pages = e0197074 | date = 16 May 2018 | pmid = 29768505 | pmc = 5955534 | doi = 10.1371/journal.pone.0197074 | doi-access = free | bibcode = 2018PLoSO..1397074G }}</ref>

==Epidemiology==
Classic [[rabies]] virus is prevalent throughout most of the world and can be carried by any warm blooded mammal. The other lyssaviruses have much less diversity in carriers. Only select [[host (biology)|host]]s can carry each of these [[viral species]]. Also, these other species are particular only to a specific geographic area. Bats are known to be an animal [[Vector (epidemiology)|vector]] for all identified lyssaviruses except the [[Mokola virus]].<ref>{{cite web |author=WHO Rabnet/CDC Map Production |title=Rabies, countries or areas at risk |date=2008 |publisher=World Health Organization |url=https://www.who.int/rabies/Global_Rabies_ITH_2008.png |url-status=dead |archive-url=https://web.archive.org/web/20101009093201/http://www.who.int/rabies/Global_Rabies_ITH_2008.png |archive-date=9 October 2010 |df=dmy-all }}</ref>

== See also ==
* [[Bat-borne virus]]

== References ==
{{Reflist}}

== Further reading ==
{{Refbegin}}
* {{cite journal | vauthors = Botvinkin AD, Poleschuk EM, Kuzmin IV, Borisova TI, Gazaryan SV, Yager P, Rupprecht CE | title = Novel lyssaviruses isolated from bats in Russia | journal = Emerging Infectious Diseases | volume = 9 | issue = 12 | pages = 1623–1625 | date = December 2003 | pmid = 14720408 | pmc = 3034350 | doi = 10.3201/eid0912.030374 }}
* {{cite journal | vauthors = Arai YT, Kuzmin IV, Kameoka Y, Botvinkin AD | title = New lyssavirus genotype from the Lesser Mouse-eared Bat (Myotis blythi), Kyrghyzstan | journal = Emerging Infectious Diseases | volume = 9 | issue = 3 | pages = 333–337 | date = March 2003 | pmid = 12643828 | pmc = 2958534 | doi = 10.3201/eid0903.020252 }}
* {{cite book |author=World Health Organization |title=WHO Expert Consultation on Rabies |url=https://www.who.int/rabies/ExpertConsultationOnRabies.pdf  |series=WHO technical report series |year=2005 |publisher=World Health Organization |location=Geneva, Switzerland |isbn=978-92-4-120931-1}}
{{Refend}}

== External links ==
{{Commons category|Lyssavirus}}
* [https://www.bv-brc.org/view/Taxonomy/11270 Rhabdoviridae]
* [https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=11286 Lyssavirus]
* [https://viralzone.expasy.org/22.html '''Viralzone''': Lyssavirus]
* [http://ictvonline.org/virusTaxonomy.asp '''ICTV''']
{{Baltimore classification}}
{{Taxonbar|from=Q940434}}

[[Category:Lyssaviruses]]
[[Category:Virus genera]]
[[Category:Chiroptera-borne diseases]]