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| __NOTOC__
| | #REDIRECT[[Hepatitis A virus]] |
| {{Hepatitis A}}
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| {{CMG}}; {{AE}} {{JS}}
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| ==Overview==
| | [[Category:Emergency mdicine]] |
| | | [[Category:Disease]] |
| ==Taxonomy==
| | [[Category:Up-To-Date]] |
| [[Viruses]]; ssRNA] [[viruses]]; [[Positive-sense ssRNA virus|ssRNA virus]]; positive-strand viruses; Picornavirales; [[Picornaviridae]]; [[Hepatovirus]]
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| ==Biology==
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| {| style="float: right;"
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| | [[File:HapatitisA.jpeg|200px|thumb|none|Electron micrograph of the Hepatitis A virus (HAV), an RNA virus that can survive up to a month at room temperature. <SMALL>Courtesy: ''[http://phil.cdc.gov/phil/home.asp Public Health Image Library (PHIL), Centers for Disease Control and Prevention (CDC)]''<ref>{{Cite web | title = http://phil.cdc.gov/phil/details.asp | url = http://phil.cdc.gov/phil/details.asp}}</ref></SMALL>]]
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| [[Hepatitis A virus]] ([[HAV]]) is a 27 nm, [[Viral envelope|non-enveloped]], icosahedral, [[Positive-sense ssRNA virus|ssRNA virus]] with a single [[serovar]]. So far, 4 different [[genotype]]s have been identified in [[hepatitis A virus]]es, all belonging to the same [[serotype]].<ref name="pmid1335657">{{cite journal| author=Lemon SM, Jansen RW, Brown EA| title=Genetic, antigenic and biological differences between strains of hepatitis A virus. | journal=Vaccine | year= 1992 | volume= 10 Suppl 1 | issue= | pages= S40-4 | pmid=1335657 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1335657 }} </ref>
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| ===Genome===
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| The [[HAV]] [[genome]] is encoded in 7474 [[nucleotides]], which are divided into three regions:
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| * 5' untranslated region, with 742 [[nucleotides]]
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| * Single reading frame encoding a 2227 [[amino acid]] [[polypeptide]], with 6681 [[nucleotides]]
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| * 3' noncoding region, with 63 [[nucleotides]]
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| The [[reading frame]] encodes a [[polypeptide]] that is processed by a [[viral]] [[protease]]. This process takes place cotranslationally, and leads to the formation of:
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| * Four structural proteins
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| * Seven nonstructural proteins
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| ==Tropism==
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| Similarly to other [[hepatitis]] viruses, the [[hepatitis A virus]] shows [[tropism]] for the [[liver cells]]. The [[hepatocytes]] represent the predominant site for [[viral replication]].<ref name="pmid9265900">{{cite journal| author=Lemon SM| title=Type A viral hepatitis: epidemiology, diagnosis, and prevention. | journal=Clin Chem | year= 1997 | volume= 43 | issue= 8 Pt 2 | pages= 1494-9 | pmid=9265900 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9265900 }} </ref>
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| ==Natural Reservoir==
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| * Humans are the only [[natural reservoir]] of the [[virus]].
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| * There are no insect or animal vectors.
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| * A chronic [[HAV]] carrier state has not been reported.
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| ==References==
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| {{Reflist|2}}
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| [[Category:Needs overview]] | |
| [[Category:Foodborne illnesses]] | |
| [[Category:hepatitis|A]] | |
| [[Category:Picornaviruses]]
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| [[Category:Viral diseases]]
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| [[Category:Mature chapter]]
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| [[Category:Infectious disease]] | | [[Category:Infectious disease]] |
| [[Category:Disease]] | | [[Category:Hepatology]] |
| | | [[Category:Gastroenterology]] |
| {{WH}}
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| {{WS}}
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