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{{Infobox - virus
| název = ''Virus hepatitidy A''
| obrázek = Hepatitis A virus 01.jpg
| popisek = HAV v elektronovém mikroskopu
| čeleď = Picornaviridae
| nk = ssRNA
| zdroj = člověk
| přenos = fekálně-orální (přímo nebo kontaminovanou vodou a potravou)
| výskyt = kosmopolitní
| onemocnění = [[virová hepatitida A]]
| diagnostika = klinický obraz, elevace [[aminotransferázy|AST a ALT]], sérologie (anti-HAV IgM)
| terapie = symptomatická, podpůrná léčba (vitaminy, [[hepatoprotektiva]])
| očkování = aktivní imunizace ([[Očkovací látky#Živé oslabené vakcíny|živá očkovací látka]], také kombinovaná vakcína proti HAV a HVB), [[pasivní imunizace]] (lidský Ig pro postexpoziční profylaxi, zmírní průběh infekce) 
}}
[[File:HAV prevalence 2005.png|thumb|right|300px|Global prevalence of hepatitis A]]
[[File:HAV prevalence 2005.png|thumb|right|300px|Global prevalence of hepatitis A]]


[[File:Jaundice eye new.jpg|thumb|300px|right|Jaundice: yellowing of the sclera in a patient with viral hepatitis A]]
[[File:Jaundice eye new.jpg|thumb|300px|right|Jaundice: yellowing of the sclera in a patient with viral hepatitis A]]


The causative agent is HAV, which is an [[RNA]] [[virus]] from the Picornaviridae family (Enteroviridae, Enterovirus 72), that acts directly cytolytically. HAV is a small virus (27-30nm), genetically homogenous, resistant to the external environment. It is exclusively human pathogen<ref name="zampachova">{{Citace
The causative agent is HAV, which is an [[RNA]] [[virus]] from the Picornaviridae family (Enteroviridae, Enterovirus 72), that acts directly cytolytically. HAV is a small virus (27-30nm), genetically homogenous, resistant to the external environment. It is exclusively human pathogen<ref name="zampachova">{{Cite
| typ = web
| type = web
| příjmení1 = Žampachová
| surname1 = Žampachová
| jméno1 = Eva
| name1 = Eva
| url = http://mujweb.cz/zampach/motol/?redirected=1521314685
| url = http://mujweb.cz/zampach/motol/?redirected=1521314685
| název = Přednášky a materiály dr. Žampachové ke stažení
| book = Přednášky a materiály dr. Žampachové ke stažení
| citováno = 2012-01-12
| citováno = 2012-01-12
}}</ref>
}}</ref>
It spreads by the faecal-oral route (“dirty hand disease”), often by contaminated food and water, rarely parenterally. The entrance gate is the digestive tract and it is excreted in faeces. Transplacental transmission is not possible.<ref name="muntau">{{Citace |typ = kniha |příjmení1 = Muntau |jméno1 = Ania Carolina|kolektiv = ne |titul = Pediatrie |vydání = 4 |místo = Praha |vydavatel = Grada |rok = 2009 |strany =  393-394|isbn = 978-80-247-2525-3}}</ref>
It spreads by the faecal-oral route (“dirty hand disease”), often by contaminated food and water, rarely parenterally. The entrance gate is the digestive tract and it is excreted in faeces. Transplacental transmission is not possible.<ref name="muntau">{{Cite |typ = book |surname1 = Muntau |jméno1 = Ania Carolina|kolektiv = ne |titul = Pediatrie |vydání = 4 |místo = Praha |vydavatel = Grada |rok = 2009 |strany =  393-394|isbn = 978-80-247-2525-3}}</ref>
The virus is highly resistant to external influences. It is excreted in faeces as early as 2 weeks before the onset of symptoms and continues for about a week (up to 2 weeks)<ref name="muntau" /> after the symptoms stop. The patient is the most contagious before the end of the incubation period.  
The virus is highly resistant to external influences. It is excreted in faeces as early as 2 weeks before the onset of symptoms and continues for about a week (up to 2 weeks)<ref name="muntau" /> after the symptoms stop. The patient is the most contagious before the end of the incubation period.  


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Vaccination with an attenuated vaccine, increased health surveillance at the site of the outbreak. By clinical examination and liver function monitoring, new cases of infections are identified. Immunolactively administered [[imunoglobulin]] (NORGA) is administered to the exposed.<noinclude>
Vaccination with an attenuated vaccine, increased health surveillance at the site of the outbreak. By clinical examination and liver function monitoring, new cases of infections are identified. Immunolactively administered [[imunoglobulin]] (NORGA) is administered to the exposed.<noinclude>
==Links==
==Links==
===Související články===
===Related articles===


*[[Virové hepatitidy]]
*[[Virové hepatitidy]]
*[[Hepatitidy]]
*[[Hepatitidy]]


===Reference===
===References===
<references />
<references />
===Zdroje===
===Sources===


*{{Citace
*{{Cite
|typ = web
|type = web
|příjmení1 = Pastor
|surname1 = Pastor
|jméno1 = Jan
|name1 = Jan
|název = Langenbeck's medical web page
|source_name = Langenbeck's medical web page
|rok =  
|year =  
|citováno = 2010
|cited = 2010
|url = http://langenbeck.webs.com
|url = http://langenbeck.webs.com
}}
}}
*{{Citace
*{{Cite
|typ = web
|typ = web
|příjmení1 = Beneš
|surname1 = Beneš
|jméno1 = Jiří
|name1 = Jiří
|název = Studijní materiály
|source_name = Studijní materiály
|rok =  
|rok =  
|citováno = 2010
|cited = 2010
|url = http://jirben.wz.cz
|url = http://jirben.wz.cz
}}
}}


===Použitá literatura===
===Literature===


*{{Citace
*{{Cite
| typ = kniha
| type = book
|korporace =
|corporation =
|příjmení1 = Havlík  |jméno1 = Jiří
|surname1 = Havlík  |jméno1 = Jiří
|kolektiv = ano
|others = ano
|titul = Infektologie
|title = Infektologie
|vydání =  2  |místo = Praha
|edition =  2  |location = Praha
|vydavatel = Avicenum  |rok = 1990  |rozsah = 393
|publisher = Avicenum  |year = 1990  |range = 393
|edice =  |svazek =
|isbn = 80-201-0062-8  
|isbn = 80-201-0062-8   |strany =
|url =
}}
}}
*{{Citace
*{{Cite
| typ = kniha
| typ = book
|korporace =
|korporace =
|příjmení1 = Lobovská  |jméno1 = Alena
|surname1 = Lobovská  |jméno1 = Alena
|kolektiv = ne
|kolektiv = ne
|titul = Infekční nemoci
|titul = Infekční nemoci

Revision as of 20:18, 30 November 2021


Global prevalence of hepatitis A
Jaundice: yellowing of the sclera in a patient with viral hepatitis A

The causative agent is HAV, which is an RNA virus from the Picornaviridae family (Enteroviridae, Enterovirus 72), that acts directly cytolytically. HAV is a small virus (27-30nm), genetically homogenous, resistant to the external environment. It is exclusively human pathogen[1] It spreads by the faecal-oral route (“dirty hand disease”), often by contaminated food and water, rarely parenterally. The entrance gate is the digestive tract and it is excreted in faeces. Transplacental transmission is not possible.[2] The virus is highly resistant to external influences. It is excreted in faeces as early as 2 weeks before the onset of symptoms and continues for about a week (up to 2 weeks)[2] after the symptoms stop. The patient is the most contagious before the end of the incubation period.

The course of infectionThe incubation period is 15-48 days.[2] First, the prodromal (“preicteric”) stage begins (dyspepsia, fatigue, fever, weight loss). This is followed by the symptomatic stage (“icteric”) - the leading symptoms are jaundice, dark urine and acholic stool. The course is milder and shorter than in VHB. Cholestatic symptoms are rare and may occur fulminantly. HAV does not cause chronic infections. .[1]

Diagnostics

Demonstration of antibodies

Diagnostics is done using anti-HAV antibodies. We perform the examination of specific IgM in serum (anti-HAV-IgM), the increase in transaminases and bilirubin and the slight increase in ALP. Negative test in immunocompetent individuals excludes infection. IgM persists in  serum for 3-6 months after infection, IgG persists long-term. The infection leaves a long-term to lifelong immunity. The main diagnostic marker.

Electron-microscopic detection of virus in faeces [1]

It can be detected in the second half of the incubation period and shortly after the onset of clinical symptoms.

Detection of antigen and RNA [1]

In stool, similar to microscopy.

Therapy

Treatment is symptomatic - rest, no alcohol, diet with carbohydrates (possibly glucose) and fat reduction. Corticosteroids only in fulminant forms.

Complications

The severity of the infection increases with age (90% are asymptomatic in young children). In 10%, it is a prolonged form, which, however, does not lead to chronicity. Chronic infection and carriers do not exist.

Complications: fulminant liver failure (rare), myocarditis, encefalopathy, cryoglobulinemia, bone marrow hypoplasia, spleen rupture, pancreatitis, Guillain-Barré syndrome.[2]

Prevention

Vaccination with an attenuated vaccine, increased health surveillance at the site of the outbreak. By clinical examination and liver function monitoring, new cases of infections are identified. Immunolactively administered imunoglobulin (NORGA) is administered to the exposed.

Links

Related articles

References

  1. Jump up to: a b c d Incomplete citation of web. ŽAMPACHOVÁ, Eva. <http://mujweb.cz/zampach/motol/?redirected=1521314685>.
  2. Jump up to: a b c d

Sources


Literature

  • HAVLÍK,. Infektologie. 2. edition. Praha : Avicenum, 1990. 393 pp. ISBN 80-201-0062-8.


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Kategorie:Infekční nemoci Kategorie:Mikrobiologie Kategorie:Gastroenterologie