Bunyavirales

Bunyavirales
Crimean-Congo hemorrhagic fever virus (CCHFV) virion and replication cycle
Virus classification Edit this classification
(unranked): Virus
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Negarnaviricota
Subphylum: Polyploviricotina
Class: Ellioviricetes
Order: Bunyavirales
Families[1]

Bunyavirales is an order of segmented negative-strand RNA viruses with mainly tripartite genomes. Member viruses infect arthropods, plants, protozoans, and vertebrates.[2] It is the only order in the class Ellioviricetes.[1] The name Bunyavirales derives from Bunyamwera,[3] where the original type species Bunyamwera orthobunyavirus was first discovered.[4] Ellioviricetes is named in honor of late virologist Richard M. Elliott for his early work on bunyaviruses.[5]

Bunyaviruses belong to the fifth group of the Baltimore classification system, which includes viruses with a negative-sense, single-stranded RNA genome. They have an enveloped, spherical virion. Though generally found in arthropods or rodents, certain viruses in this order occasionally infect humans. Some of them also infect plants.[6] In addition, there is a group of bunyaviruses whose replication is restricted to arthropods and is known as insect-specific bunyaviruses.[7]

A majority of bunyaviruses are vector-borne. With the exception of Hantaviruses and Arenaviruses, all viruses in the Bunyavirales order are transmitted by arthropods (mosquitos, tick, or sandfly). Hantaviruses are transmitted through contact with rodent feces. Incidence of infection is closely linked to vector activity, for example, mosquito-borne viruses are more common in the summer.[6]

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 is done in biosafety level 4 laboratories. They are also the cause of severe fever with thrombocytopenia syndrome.[8]

Hantaviruses are another medically important member of the order Bunyvirales. They are found worldwide, and are relatively common in Korea, Scandinavia (including Finland), Russia, western North America and parts of South America. Hantavirus infections are 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 Scandinavia).[9] The antibody reaction plays an important role in decreasing levels of viremia.

  1. ^ a b "Virus Taxonomy: 2020 Release". International Committee on Taxonomy of Viruses (ICTV). March 2021. Retrieved 19 May 2021.
  2. ^ Herath, Venura; Romay, Gustavo; Urrutia, Cesar D.; Verchot, Jeanmarie (September 2020). "Family Level Phylogenies Reveal Relationships of Plant Viruses within the Order Bunyavirales". Viruses. 12 (9): 1010. doi:10.3390/v12091010. PMC 7551631. PMID 32927652.
  3. ^ "ICTV 9th Report (2011) Bunyaviridae". International Committee on Taxonomy of Viruses (ICTV). Retrieved 31 January 2019. Bunya: from Bunyamwera, place in Uganda, where type virus was isolated.
  4. ^ Smithburn, K. C.; Haddow, A. J.; Mahaffy, A. F. (March 1946). "A Neurotropic Virus Isolated from Aedes Mosquitoes Caught in the Semliki Forest". The American Journal of Tropical Medicine and Hygiene. s1-26 (2): 189–208. doi:10.4269/ajtmh.1946.s1-26.189. ISSN 1476-1645. OCLC 677158400. PMID 21020339.
  5. ^ Wolf, Yuri; Krupovic, Mart; Zhang, Yong Zhen; Maes, Piet; Dolja, Valerian; Koonin, Eugene V.; Kuhn, Jens H. "Megataxonomy of negative-sense RNA viruses" (docx). International Committee on Taxonomy of Viruses (ICTV). Retrieved 12 January 2019.[dead link]
  6. ^ a b Plyusnin, A; Elliott, RM, eds. (2011). Bunyaviridae: Molecular and Cellular Biology. Caister Academic Press. ISBN 978-1-904455-90-5.
  7. ^ Elrefaey, Ahmed ME; Abdelnabi, Rana; Rosales Rosas, Ana Lucia; Wang, Lanjiao; Basu, Sanjay; Delang, Leen (September 2020). "Understanding the Mechanisms Underlying Host Restriction of Insect-Specific Viruses". Viruses. 12 (9): 964. doi:10.3390/v12090964. PMC 7552076. PMID 32878245.
  8. ^ Yu XJ, Liang MF, Zhang SY, et al. (April 2011). "Fever with thrombocytopenia associated with a novel bunyavirus in China". N. Engl. J. Med. 364 (16): 1523–32. doi:10.1056/NEJMoa1010095. PMC 3113718. PMID 21410387.
  9. ^ Walter Muranyi; Udo Bahr; Martin Zeier; Fokko J. van der Woude (2005). "Hantavirus Infection". Journal of the American Society of Nephrology. 16 (12): 3669–3679. doi:10.1681/ASN.2005050561. PMID 16267154.