Bunyavirales: Difference between revisions

{{shortShort description|Order of negative-sense single-stranded RNA viruses}}

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| subdivision_ref = <ref name=ICTV >{{cite web |title=Virus Taxonomy: 20182020 Release |url=https://talkictv.ictvonline.orgglobal/taxonomy/ |websitepublisher=International Committee on Taxonomy of Viruses (ICTV) |accessdatedate=30March January 20192021 |languageaccess-date=en19 |date=OctoberMay 20182021}}</ref>

* ''[[Arenaviridae]]''

* ''[[Cruliviridae]]''

* ''[[Fimoviridae]]''

* ''[[Hantaviridae]]''

* ''[[Leishbunyaviridae]]''

* ''[[Mypoviridae]]''

* ''[[Nairoviridae]]''

* ''[[Peribunyaviridae]]''

* ''[[Phasmaviridae]]''

* ''[[Phenuiviridae]]''

* ''[[Tospoviridae]]''

* ''[[Wupedeviridae]]''

'''''Bunyavirales''''' is an order of segmented [[negative-sense single-strandedstrand RNA virus]]es. Itwith ismainly thetripartite onlygenomes. orderMember inviruses theinfect class[[arthropod]]s, '''''Ellioviricetes'''''[[plant]]s, [[protozoa]]ns, and [[vertebrate]]s.<ref name=ICTV":0">{{citationCite journal|titlelast1=VirusHerath|first1=Venura|last2=Romay|first2=Gustavo|last3=Urrutia|first3=Cesar Taxonomy: 2018 ReleaseD.|last4=Verchot|first4=Jeanmarie|date=September 2020|publishertitle=InternationalFamily CommitteeLevel onPhylogenies TaxonomyReveal Relationships of Plant Viruses within the Order Bunyavirales|urljournal=https://talkViruses|language=en|volume=12|issue=9|pages=1010|doi=10.ictvonline.org3390/taxonomy/ v12091010|accessdatepmid=201832927652|pmc=7551631|doi-12-02access=free}}</ref> It is the only order in the class '''''Ellioviricetes'''''.<ref name=ICTV /> The name ''Bunyavirales'' derives from [[Bunyamwera]],<ref name="ICTV9">{{cite web |title=ICTV 9th Report (2011) ''Bunyaviridae'' |url=https://talkictv.ictvonline.orgglobal/ictv-reportsreport/ictv_9th_reportchapter/negative-sense-rna-viruses-2011/w/negrna_viruses/205/bunyaviridaeperibunyaviridae |website=International Committee on Taxonomy of Viruses (ICTV) |accessdateaccess-date=31 January 2019 |language=en |quote=Bunya: from Bunyamwera, place in Uganda, where type virus was isolated.}}</ref> where the original [[type species]] ''[[Bunyamwera orthobunyavirus]]'' was first discovered.<ref name="Smithburn">{{cite journal |last1=Smithburn |first1=K. C. |last2=Haddow |first2=A. J. |last3=Mahaffy |first3=A. F. |title=A Neurotropic Virus Isolated from Aedes Mosquitoes Caught in the Semliki Forest |journal=The American Journal of Tropical Medicine and Hygiene |date=March 1946 |volume=s1-26 |issue=2 |pages=189–208 |doi=10.4269/ajtmh.1946.s1-26.189 |pmid=21020339 |language=en |issn=1476-1645 |oclc=677158400}}</ref> ''Ellioviricetes'' is named in honor of late virologist [[Richard M. Elliott (virologist)|Richard M. Elliott]] for his early work on bunyaviruses.<ref name="2017.006M">{{cite web |last1=Wolf |first1=Yuri |last2=Krupovic |first2=Mart |last3=Zhang |first3=Yong Zhen |author-link3=Zhang Yongzhen |last4=Maes |first4=Piet |last5=Dolja |first5=Valerian |last6=Koonin |first6=Eugene V. |last7=Kuhn |first7=Jens H. |title=Megataxonomy of negative-sense RNA viruses |url=https://talk.ictvonline.org/cfs-file/__key/telligent-evolution-components-attachments/13-237-00-00-00-00-76-13/2017.006M.A.v1.Negarnaviricota.docx |website=International Committee on Taxonomy of Viruses (ICTV) |accessdateaccess-date=12 January 2019 |language=en |format=docx}}{{dead link|date=January 2023|bot=medic}}{{cbignore|bot=medic}}</ref>

This order of virusesBunyaviruses belong to the fifth group of the [[Baltimore classification|Baltimore classification system]], thewhich so-calledincludes negative-senseviruses single-strandedwith ribonucleic acida [[NegativeSense (molecular biology)|negative-sense]], single-stranded RNA virus|(−)ssRNA]]genome. They have envelopedan [[RNAViral virusenvelope|enveloped]]es, spherical virion. Though generally found in [[arthropod]]s or rodents, certain viruses in this order occasionally infect humans. Some of them also infect plants.<ref name= PlyusninAElliottRM>{{cite book |editor1=Plyusnin, A |editor2=Elliott, RM | year=2011 | title=Bunyaviridae: Molecular and Cellular Biology | publisher=[[Caister Academic Press]] | isbn= 978-1-904455-90-5}}</ref> In addition, there is a classgroup of these virusesbunyaviruses whose replication has been shownis restricted to arthropods, and is known as insect-specific bunyaviruses.<ref>{{Cite journal|lastlast1=Elrefaey|firstfirst1=Ahmed ME|last2=Abdelnabi|first2=Rana|last3=Rosales Rosas|first3=Ana Lucia|last4=Wang|first4=Lanjiao|last5=Basu|first5=Sanjay|last6=Delang|first6=Leen|date=September 2020|title=Understanding the Mechanisms Underlying Host Restriction of Insect-Specific Viruses|url=https://www.mdpi.com/1999-4915/12/9/964|journal=Viruses|language=en|volume=12|issue=9|pages=964|doi=10.3390/v12090964|pmid=32878245|pmc=7552076|doi-access=free}}</ref>

A majority of bunyaviruses are vector-borne. With the exception of [[Hantaviruses]] and [[Arenavirus]]es, all viruses in the ''Bunyavirales'' order are [[Arbovirus|transmitted by arthropods]] (mosquitos, tick, or sandfly). Hantaviruses are transmitted through contact with [[deer micerodent]] feces. Incidence of infection is closely linked to vector activity, for example, mosquito-borne viruses are more common in the summer.<ref name="PlyusninAElliottRM" />

Human infections with certain members of ''Bunyavirales'', such as ''[[Crimean-Congo hemorrhagic fever orthonairovirus]]'', are associated with high levels of morbidity and mortality, consequently handling of these viruses mustis occurdone with ain [[Biosafetybiosafety level 4]] laboratorylaboratories. They are also the cause of [[severe fever with thrombocytopenia syndrome]].<ref name="nejm">{{cite journal |vauthors=Yu XJ, Liang MF, Zhang SY |title=Fever with thrombocytopenia associated with a novel bunyavirus in China |journal=N. Engl. J. Med. |volume=364 |issue=16 |pages=1523–32 |date=April 2011 |pmid=21410387 |pmc=3113718 |doi=10.1056/NEJMoa1010095 |display-authors=etal}}</ref>

[[Hantavirus]]es is are another medically- important member of the familyorder ''[[Hantaviridae]]Bunyvirales''. ItThey isare found worldwide, and are relatively common in [[Korea]], broader [[Scandinavia]] (including [[Finland]]), [[Russia]], western North America and parts of South America. ItHantavirus infections isare associated with high fever, lung edema, and pulmonary failure. The mortality rate varies significantly depending on the form, being up to 50% in New World hantaviruses (the Americas), up to 15% in Old World hantaviruses (Asia and Europe), and as little as 0.1% in [[Puumala virus]] (mostly broader Scandinavia).<ref>{{cite journal | author1=Walter Muranyi | author2=Udo Bahr | author3=Martin Zeier | author4=Fokko J. van der Woude | year=2005 | title=Hantavirus Infection | journal=Journal of the American Society of Nephrology | volume=16 | issue=12 |pages=3669–3679 | doi=10.1681/ASN.2005050561 | pmid=16267154 | doi-access=free }}</ref> The antibody reaction plays an important role in decreasing levels of [[viremia]].

[[File:Peribunyavirus_virion_structurePeribunyavirus virion structure.gif|thumb|Peribunyavirus virion structure]]

''Bunyaviridae''Bunyaviruses have bi- or tripartite [[genome]]s consisting of a large (L) and small(s), or large (L), medium (M), and small (S) RNA segment. These RNA segments are single-stranded, and exist in a helical formation within the virion. Besides, they exhibit a pseudo-circular structure due to each segment's complementary ends. The L segment encodes the [[RNA Dependent-dependent RNA- polymerase]], necessary for viral RNA replication and mRNA synthesis. The M segment encodes the viral [[glycoprotein]]s, which project from the viral surface and aid the virus in attaching to and entering the host cell. The S segment encodes the [[nucleocapsid]] protein (N).<ref>{{Cite journal|lastlast1=Ariza|firstfirst1=A.|last2=Tanner|first2=S. J.|last3=Walter|first3=C. T.|last4=Dent|first4=K. C.|last5=Shepherd|first5=D. A.|last6=Wu|first6=W.|last7=Matthews|first7=S. V.|last8=Hiscox|first8=J. A.|last9=Green|first9=T. J.|date=2013-06-01|title=Nucleocapsid protein structures from orthobunyaviruses reveal insight into ribonucleoprotein architecture and RNA polymerization|journal=Nucleic Acids Research|volume=41|issue=11|pages=5912–5926|doi=10.1093/nar/gkt268|issn=0305-1048|pmc=3675483|pmid=23595147}}</ref>

Most ofbunyaviruses thehave ''Bunyaviridae'' havea negative -sense L and M segment. The S segment of the genus ''[[Phlebovirus]]'',<ref name="phlebovirus">{{cite journal |last1=Elliott |first1=Richard M |last2=Brennan |first2=Benjamin |title=Emerging phleboviruses |journal=Current Opinion in Virology |date=April 2014 |volume=5 |issue=100 |pages=50–57 |doi=10.1016/j.coviro.2014.01.011|pmid=24607799 |pmc=4031632 }}</ref> and both M and S segment of the genus ''[[Tospovirus]]'' are [[ambisense]].<ref name="tospovirus">{{cite journal |last1=Lima |first1=R. N. |last2=De Oliveira |first2=A. S. |last3=Leastro |first3=M. O. |last4=Blawid |first4=R. |last5=Nagata |first5=T. |last6=Resende |first6=R. O. |last7=Melo |first7=F. L. |title=The complete genome of the tospovirus Zucchini lethal chlorosis virus |journal=Virology Journal |date=7 July 2016 |volume=13 |issue=1 |pages=123 |doi=10.1186/s12985-016-0577-4|pmid=27388209 |pmc=4936248 |doi-access=free }}</ref> Ambisense means that some of the genes on the RNA strand are negative sense and others are positive sense. The ambisense S segment codes for the viral [[nucleoprotein]] (N) in the negative sense and a [[NonstructuralBunyaviridae Proteinnonstructural S proteins|nonstructural protein]] (NSs) in the positive sense. The ambisense M segment codes for [[glycoprotein]] (GP) in the negative sense and a nonstructural protein (NSm) in the positive sense.<ref name="tospovirus" />

TotalThe total genome size ranges from 10.5 to 22.7 [[kilo base pair|kbp]].<ref name="ICTVdb">{{cite web |url=https://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/00.011.htm |publisher=ICTVdB—The Universal Virus Database, version 4 |title=00.011. ''Bunyaviridae'' |year=2006 |accessdateaccess-date=2009-01-01}}</ref>

=== ReplicationLife cycle ===

[[File:ONSR.Nairo.Fig3.v2_WEBv2 WEB.png|thumb|Nairovirus life cycle.]]

ThisThe [[ambisense]] arrangementgenome requires two rounds of transcription to be carried out. First, the negative-sense RNA is transcribed to produce mRNA and a full-length replicative intermediate. From this intermediate, a subgenomic mRNA encoding the small segment nonstructural protein is produced while the polymerase produced following the first round of transcription can now replicate the full-length RNA to produce viral genomes.{{cn|date=October 2022}}

BunyavirusBunyaviruses RNA replicatesreplicate in the [[cytoplasm]], while the viral proteins transit through the [[endoplasmic reticulum|ER]] and [[Golgi apparatus]]. Mature virions bud from the Golgi apparatus into vesicles which are transported to the cell surface.{{cn|date=October 2022}}

=== ClassificationTransmission ===

Bunyaviruses that cause disease in humans include:{{cn|date=April 2023}}

* [[California encephalitis virus]], [[Jamestown Canyon virus]], [[La Crosse encephalitis virus]], [[JamestownOropouche Canyon virusorthobunyavirus]], and [[Snowshoe hare virus]] (vector: mosquitoes; Familyfamily: Peribunyaviridae);

* [[Hantavirus]] reservoir: small mammals or rodents (vector: aerosolized excreta from these mammals; Familyfamily: Hantaviridae);

* [[Crimean–Congo hemorrhagic fever]] reservoir and (vector: ticks,; amplifying hosts and vector: small mammals, domestic mammals; Familyfamily: [[Nairoviridae]]);

* [[Rift Valley fever]] (reservoir: bats; vector: mosquitoes; amplifying hosts: small mammals,and domestic mammals; Familyfamily: [[Phenuiviridae]]);

* [[Bwamba Fever]] (reservoir: monkeys; vector: mosquitoes,; amplifying hosts: donkeys; Familyfamily: Peribunyaviridae);

* [[Severe fever with thrombocytopenia syndrome]] (vector: ticks);

* [[Lassa fever]] and [[Argentine hemorrhagic fever]] (reservoir: rodents; vector: aerosolized excreta from these mammals; Familyfamily: Arenaviridae).

Bunyaviruses have segmented genomes, making them capable of rapid recombinationreassortment and increasing the risk of outbreak.<ref>{{Citation| doi = 10.1016/j.virol.2013.07.030| title = Viruses of the family Bunyaviridae: Are all available isolates reassortants?| date = November 2013| last1 = Briese| first1 = Thomas| last2 = Calisher| first2 = Charles H.| last3 = Higgs| first3 = Stephen| journal = Virology| volume = 446| issue = 1–2| pages = 207–216| pmid = 24074583| hdl = 2097/17679| hdl-access = free}}</ref><ref>{{Cite journal| doi = 10.3390/v6114373| issn = 1999-4915| volume = 6| issue = 11| pages = 4373–4397| last1 = Horne| first1 = Kate McElroy| last2 = Vanlandingham| first2 = Dana L.| title = Bunyavirus-Vector Interactions| journal = Viruses| date = 2014-11-13| pmid = 25402172| pmc = 4246228| doi-access = free}}</ref> The bunyavirus that causes [[severe fever with thrombocytopenia syndrome]] can undergo recombination both by reassortment of [[genome]] segments and by intragenic [[homologous recombination]].<ref>Lv Q, Zhang H, Tian L, Zhang R, Zhang Z, Li J, Tong Y, Fan H, Carr MJ, Shi W. Novel sub-lineages, recombinants and reassortants of severe fever with thrombocytopenia syndrome virus. Ticks Tick Borne Dis. 2017 Mar;8(3):385-390. doi: 10.1016/j.ttbdis.2016.12.015. Epub 2017 Jan 3. {{PMID|28117273}}</ref><ref>He CQ, Ding NZ. Discovery of severe fever with thrombocytopenia syndrome bunyavirus strains originating from intragenic recombination. J Virol. 2012 Nov;86(22):12426-30. doi: 10.1128/JVI.01317-12. Epub 2012 Aug 29. {{PMID|22933273}}</ref> Bunyaviridae are transmitted by hematophagous arthropods including mosquitoes, midges, flies, and ticks. The viral incubation period is about 48 hours. Symptomatic infection typically causes non-specific [[flu-like]] symptoms with fever lasting for about three days. Because of their [[non-specific symptoms]], Bunyavirus infections are frequently mistaken for other illnesses. For example, Bwamba fever is often mistaken for malaria.<ref>{{Cite book| edition = 6| publisher = Mosby| isbn = 9780323054706| author = Patrick R. Murray, Ken S. Rosenthal and Michael A. Pfaller|title = Medical Microbiology, 6e| location = Philadelphia| date = 2008-12-24}}</ref>

Prevention depends on the reservoir, amplifying hosts and how the viruses are transmitted, i.e. the vector, whether ticks or mosquitoes and which animals are involved. Preventive measures include general hygiene, limiting contact with vector saliva, urine, feces, or bedding. There is no licensed vaccine for bunyaviruses. As precautions Cache Valley virus and Hantavirus research are conducted in BSL-2 (or higher), Rift Valley Fever virus research is conducted in BSL-3 (or higher), Congo-Crimean Hemorrhagic Fever virus research is conducted in BSL-4 laboratories.{{cn|date=October 2022}}

* [http://www.virology.net/Big_Virology/BVRNAbunya.html The Big Picture Book of Viruses: ''Bunyaviridae''] {{Webarchive|url=https://web.archive.org/web/20160511185402/http://www.virology.net/Big_Virology/BVRNAbunya.html |date=2016-05-11 }}

* [https://web.archive.org/web/20151007112957/http://vbrc.org/query.asp?web_taxonomy=Bunyaviridae Bunyaviridae Genomes]&mdash;database—database search results from the [http://www.vbrc.org/ Viral Bioinformatics Resource Center]

* {{cite web |title=''Bunyaviridae'' |work=NCBI Taxonomy Browser |url=https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=11571 |id=11571}}