Hantavirus 416945 222783191 2008-07-01T02:30:03Z Sabedon 2083035 /* External links */ [[Category:Microbiology]] {{Refimprove|date=January 2008}} {{Taxobox <!-- Color parameter is not needed -- automatically assigned --> | name = ''Hantavirus'' | image = Sin Nombre hanta virus TEM PHIL 1136 lores.jpg | image_caption = Transmission electron micrograph of the Sin Nombre Hantavirus | virus_group = v | familia = ''[[Bunyaviridae]]'' | genus = '''''Hantavirus''''' | subdivision_ranks = Species | subdivision = ''[[Andes virus]]'' (ANDV) <br> ''[[Bayou virus]]'' (BAYV) <br> ''[[Black Creek Canal virus]]'' (BCCV) <br> ''[[Cano Delgadito virus]]'' (CADV) <br> ''[[Choclo virus]]'' (CHOV) <br> ''[[Dobrava-Belgrade virus]]'' (DOBV) <br> ''[[Hantaan virus]]'' (HTNV) <br> ''[[Isla Vista virus]]'' (ISLAV) <br> ''[[Khabarovsk virus]]'' (KHAV) <br> ''[[Laguna Negra virus]]'' (LANV) <br> ''[[Muleshoe virus]]'' (MULV) <br> ''[[New York virus]]'' (NYV) <br> ''[[Prospect Hill virus]]'' (PHV) <br> ''[[Puumala virus]]'' (PUUV) <br> ''[[Rio Mamore virus]]'' (RIOMV) <br> ''[[Rio Segundo virus]]'' (RIOSV) <br> ''[[Seoul virus]]'' (SEOV) <br> ''[[Sin Nombre virus]]'' (SNV) <br> ''[[Thailand virus]]'' (THAIV) <br> ''[[Thottapalayam virus]]'' (TPMV) <br> ''[[Topografov virus]]'' (TOPV) <br> ''[[Tula virus]]'' (TULV) <br> ''[[Akabane virus]]'' <br> ''[[Bakau virus]]'' <br> ''[[Bunyamwera virus]]'' <br> }} '''Hantaviruses''' belong to the '''[[bunyaviridae]]''' family of [[virus]]es. There are 7 genera within the bunyaviridae family: bunyavirus, [[phlebovirus]], [[nairovirus]], [[tospovirus]],[[orthobunyavirus]], [[unclassfied bunyavirus]] and hantavirus. Each is made up of 3 negative-sensed, single-stranded genomic segments, and so are classified as negative sense [[RNA virus]]es. All these genera include [[arthropod]]-borne viruses, with the exception of hantavirus, which is a genus of [[rodent]]-borne agents. The word ''hantavirus'' is derived from the [[Hantan River]], where the Hantaan virus (the etiologic agent of Korean hemorrhagic fever) was first isolated by Dr. [[Lee Ho-Wang]]. The disease associated with Hantaan virus is called '''Korean hemorrhagic fever''' (a term that is no longer in use) or '''hemorrhagic fever with renal syndrome''' (HFRS), a term that is accepted by the [[World Health Organization]]. ==History== The Hantaviruses constitute a relatively newly discovered class of virus; the disease entity HFRS was first recognized by Western medicine during the [[Korean War]] in the early 1950s. In [[1993]], a newly-recognized species of hantavirus was found to be behind the '''Hantavirus cardiopulmonary syndrome''' (HCPS, also called HPS) caused by the [[Sin Nombre virus]] ([[Spanish language|Spanish]] for "nameless virus") in [[New Mexico]] and other [[Four Corners (United States)|Four Corners]] states. In addition to Hantaan virus and Sin Nombre virus, several other hantaviri have been implicated as etiologic agents for either HFRS or HCPS. [[University of New Mexico]] professor [[Terry Yates]] is credited with tracing the source of the deadly [[1993]] outbreak to the deer mouse.<ref name=bg> {{cite news |first=Matt |last=Schudel |title=Terry Yates, 57; biologist found source of hantavirus |url=http://www.boston.com/bostonglobe/obituaries/articles/2007/12/24/terry_yates_57_biologist_found_source_of_hantavirus/ |work= [[Washington Post]] |publisher=[[Boston Globe]] |date=2007-12-24 |accessdate=2007-01-04}}</ref> ==Geographic distribution and epidemiology== [[Image:Sigmodon hispidus1.jpg| thumb | 245px | left | The cotton rat [[Sigmodon hispidus]] is a hantavirus carrier that becomes a threat when it enters human habitation in rural and suburban areas.]] Regions especially affected by HFRS include [[China]], the [[Korean Peninsula]], [[Russia]] (Hantaan, Puumala and Seoul viruses), and northern and western [[Europe]] ([[Puumala virus|Puumala]] and Dobrava viruses). Regions with the highest incidences of HCPS include Patagonian [[Argentina]], [[Chile]], [[Brazil]], the [[United States]], [[Canada]], and [[Panama]], where a milder form of disease that spares the heart has been recognized. The two agents of HCPS in [[South America]] are [[Andes virus]] (also called Oran, Castelo de Sonhos, Lechiguanas, Juquitiba, Araraquara, and Bermejo viruses, among many other synonyms), which is the only hantavirus that has shown (only in a few clusters of cases) an interpersonal form of transmission, and [[Laguna Negra virus]], an extremely close relative of the previously-known Rio Mamore virus. In the U.S., minor cases of HCPS include [[New York virus]], [[Bayou virus]], and possibly [[Black Creek Canal virus]]. As of July of 2007, six states had reported 30 or more cases of Hantavirus since 1993 - [[New Mexico]] (69), [[Colorado]] (49), [[Arizona]] (46), [[California]] (43), [[Texas]] (33), and [[Washington]] (30). Other states reporting a significant number of cases include [[Montana]] (25), [[Idaho]] (19), and [[Utah]] (24). With only 7 cases, [[Oregon]] has a notably lower attack rate overall and relative to population, compared to other Western states. ==Virology== Like other members of the bunyavirus family, hantaviruses are enveloped viruses with a genome that consists of three single-stranded, negative sense RNA segments designated S (small), M (medium), and L (large). The S RNA encodes the [[nucleocapsid]] (N) protein. The M RNA encodes a [[polyprotein]] that is cotranslationally cleaved to yield the envelope [[glycoprotein]]s G1 and G2. The L RNA encodes the L protein, which functions as the viral transcriptase/replicase. Within [[virion]]s, the genomic RNAs of hantaviruses are thought to complex with the N protein to form helical nucleocapsids, the RNA component of which circularizes due to sequence complementarity between the 5' and 3' terminal sequences of each genomic segment. Entry into host cells is thought to occur by attachment of virions to cellular receptors and subsequent [[endocytosis]]. Nucleocapsids are introduced into the cytoplasm by pH-dependent fusion of the virion with the [[endosomal membrane]]. Transcription of viral genes must be initiated by association of the L protein with the three nucleocapsid species. In addition to transcriptase and replicase functions, the viral L protein is also thought to have an endonuclease activity that cleaves cellular messenger RNAs (mRNAs) for the production of capped primers used to initiate transcription of viral mRNAs. As a result of this "cap snatching," the mRNAs of hantaviruses are capped and contain nontemplated 5' terminal extensions. The G1 (aka Gn) and G2 (Gc) glycoproteins form [[hetero-oligomers]] and are then transported from the [[endoplasmic reticulum]] to the [[Golgi complex]], where [[glycosylation]] is completed. The L protein produces nascent genomes by replication via a positive-sense RNA intermediate. Hantavirus virions are believed to assemble by association of nucleocapsids with glycoproteins embedded in the membranes of the Golgi, followed by budding into the [[Golgi cisternae]]. Nascent virions are then transported in secretory [[vesicle]]s to the [[plasma membrane]] and released by [[exocytosis]]. ==Symptoms== ====Renal syndrome==== Hantavirus has an [[incubation time]] of 2-4 weeks in humans, before symptoms of infection occur. These symptoms can be split into five phases: * '''Febrile phase''': Symptoms include [[fever]], chills, [[malaise]], [[headache]]s, [[nausea]], [[abdominal pain|abdominal]] and [[back pain]], [[respiratory]] problems such as the ones common in the [[influenza]] [[virus]], as well as gastro-intestinal problems. These symptoms normally occur for 3-7 days. * '''Hypotensive phase''': This occurs when the blood platelet levels drop and symptoms can lead to [[tachycardia]] and [[hypoxemia]]. This phase can last for 2 days. * '''Oliguric phase''': This phase lasts for 3-7 days and is characterised by the onset of [[renal failure]] and [[proteinuria]] occurs. * '''Diuretic phase''': This is characterized by [[diuresis]] of 3-6L per day, which can last for a couple of days up to weeks. * '''Convalescent phase''': This is normally when recovery occurs and symptoms begin to improve. ====Hantavirus (cardio-)pulmonary syndrome==== Hantavirus pulmonary syndrome (HPS) is a deadly disease transmitted by infected rodents through urine, droppings, or saliva. Humans can contract the disease when they breathe in aerosolized virus. HPS was first recognized in 1993 and has since been identified throughout the United States. Although rare, HPS is potentially deadly. Rodent control in and around the home remains the primary strategy for preventing hantavirus infection. These symptoms, which are very similar to HFRS, include [[tachycardia]] and [[tachypnoea]]. Such conditions can lead to a cardiopulmonary phase, where [[cardiovascular]] shock can occur, and hospitalization of the patient is required. ==Pathogenesis== The pathogenesis of Hantavirus infections is unclear as there is a lack of animal models (rats and mice do not seem to acquire severe disease). While the primary replication site is not clear, in both HFRS and HPS, the main effect is in the blood vessels. There is increased vascular permeability and decreased blood pressure due to endothelial dysfunction. In HFPS, the most dramatic damage is seen in the kidneys, whereas in HPS, the lungs and spleen are most affected. ==See also== * [[Puumala virus]], a hantavirus carried in [[bank vole]]s, which cause [[Nephropathia epidemica]] in humans. ==References== {{reflist}} ==External links== *[http://www.scienceandfilm.org/films.php?film_id=22 Sloan Science and Film / Short Films / Muerto Canyon] by Jen Peel 29 minutes *[http://bvs.insp.mx/articulos/5/22/092001.htm "Hantaviruses, with emphasis on Four Corners Hantavirus"] by Brian Hjelle, M.D., Department of Pathology, School of Medicine, University of New Mexico *[http://www.cdc.gov/ncidod/diseases/hanta/hps/noframes/phys/technicalinfoindex.htm CDC's Hantavirus Information page] {{Viral diseases}} All About Hantavirus. Technical Information Index Centers for Disease Control and Prevention http://www.cdc.gov/ncidod/diseases/hanta/hps/noframes/phys/technicalinfoindex.htm [[Category:Viral diseases]] [[Category:Bunyaviruses]] [[Category:Hemorrhagic fevers]] [[Category:Rat carried diseases]] [[Category:Microbiology]] [[de:Hantaviren]] [[es:Infecciones por Hantavirus]] [[fr:Hantavirus]] [[ko:한타바이러스]] [[nl:Hantavirus]] [[ja:腎症候性出血熱]] [[pl:Hantawirusowy zespół płucny]] [[fi:Hantavirukset]] [[sv:Hantaanvirus]]