Hepatitis E causes: Difference between revisions

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:*[[Methyltransferase]]
:*[[Methyltransferase]]
:*[[RNA]] [[helicase]]
:*[[RNA]] [[helicase]]
:*[[RNA]]-dependent [[RNA]] [[helicase]]
:*[[RNA]]-dependent [[RNA]] [[polimerase]]
*ORF2 - contains de protein of the viral capsid, responsible for:
*ORF2 - contains de protein of the viral capsid, responsible for:
:*Viral assembly<ref name="pmid9311793">{{cite journal| author=Li TC, Yamakawa Y, Suzuki K, Tatsumi M, Razak MA, Uchida T et al.| title=Expression and self-assembly of empty virus-like particles of hepatitis E virus. | journal=J Virol | year= 1997 | volume= 71 | issue= 10 | pages= 7207-13 | pmid=9311793 | doi= | pmc=PMC192060 | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9311793  }} </ref>
:*Viral assembly<ref name="pmid9311793">{{cite journal| author=Li TC, Yamakawa Y, Suzuki K, Tatsumi M, Razak MA, Uchida T et al.| title=Expression and self-assembly of empty virus-like particles of hepatitis E virus. | journal=J Virol | year= 1997 | volume= 71 | issue= 10 | pages= 7207-13 | pmid=9311793 | doi= | pmc=PMC192060 | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9311793  }} </ref>
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The [[natural reservoir]] of [[HEV]] is yet to be identified.  Different observations have suggested different reservoirs:
The [[natural reservoir]] of [[HEV]] is yet to be identified.  Different observations have suggested different reservoirs:
*Prolonged fecal shedding from patients with history of the disease has been suggested. However, the duration of viral shedding in feces is not compatible with this hypothesis.<ref name="pmid11009149">{{cite journal| author=Aggarwal R, Kini D, Sofat S, Naik SR, Krawczynski K| title=Duration of viraemia and faecal viral excretion in acute hepatitis E. | journal=Lancet | year= 2000 | volume= 356 | issue= 9235 | pages= 1081-2 | pmid=11009149 | doi=10.1016/S0140-6736(00)02737-9 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11009149  }} </ref>
*Prolonged fecal shedding from patients with history of the disease has been suggested. However, the duration of viral shedding in feces is not compatible with this hypothesis.<ref name="pmid11009149">{{cite journal| author=Aggarwal R, Kini D, Sofat S, Naik SR, Krawczynski K| title=Duration of viraemia and faecal viral excretion in acute hepatitis E. | journal=Lancet | year= 2000 | volume= 356 | issue= 9235 | pages= 1081-2 | pmid=11009149 | doi=10.1016/S0140-6736(00)02737-9 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11009149  }} </ref>
*Environmental reservoir was suggested following detection of [[HEV]] in sewages.<ref name="pmid17935174">{{cite journal| author=Ippagunta SK, Naik S, Sharma B, Aggarwal R| title=Presence of hepatitis E virus in sewage in Northern India: frequency and seasonal pattern. | journal=J Med Virol | year= 2007 | volume= 79 | issue= 12 | pages= 1827-31 | pmid=17935174 | doi=10.1002/jmv.21017 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17935174  }} </ref>
*Environmental reservoir was suggested following detection of [[HEV]] in sewages.<ref name="pmid17935174">{{cite journal| author=Ippagunta SK, Naik S, Sharma B, Aggarwal R| title=Presence of hepatitis E virus in sewage in Northern India: frequency and seasonal pattern. | journal=J Med Virol | year= 2007 | volume= 79 | issue= 12 | pages= 1827-31 | pmid=17935174 | doi=10.1002/jmv.21017 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17935174  }} </ref>
*Continuous fecal shedding from [[asymptomatic]] patients was suggested as a form of maintenance of the [[HEV|virus]], contaminating water supplies.<ref name="pmid21932388">{{cite journal| author=Aggarwal R, Jameel S| title=Hepatitis E. | journal=Hepatology | year= 2011 | volume= 54 | issue= 6 | pages= 2218-26 | pmid=21932388 | doi=10.1002/hep.24674 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21932388  }} </ref>
*Continuous fecal shedding from [[asymptomatic]] patients was suggested as a form of maintenance of the [[HEV|virus]], contaminating water supplies.<ref name="pmid21932388">{{cite journal| author=Aggarwal R, Jameel S| title=Hepatitis E. | journal=Hepatology | year= 2011 | volume= 54 | issue= 6 | pages= 2218-26 | pmid=21932388 | doi=10.1002/hep.24674 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21932388  }} </ref>
*The existence of an animal reservoir is supported by the detection of anti-[[HEV]] antibodies in different species.<ref name="pmid21932388">{{cite journal| author=Aggarwal R, Jameel S| title=Hepatitis E. | journal=Hepatology | year= 2011 | volume= 54 | issue= 6 | pages= 2218-26 | pmid=21932388 | doi=10.1002/hep.24674 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21932388  }} </ref>
*The existence of an animal reservoir is supported by the detection of anti-[[HEV]] antibodies in different species.<ref name="pmid21932388">{{cite journal| author=Aggarwal R, Jameel S| title=Hepatitis E. | journal=Hepatology | year= 2011 | volume= 54 | issue= 6 | pages= 2218-26 | pmid=21932388 | doi=10.1002/hep.24674 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21932388  }} </ref>



Revision as of 21:40, 26 August 2014

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: João André Alves Silva, M.D. [2]

Overview

Taxonomy

Viruses; ssRNA viruses; ssRNA positive-strand viruses; Hepeviridae; Hepevirus; Hepatitis E virus[1]

Biology

Hepatitis E virus Courtesy: Centers for Disease Control and Prevention[2]

The viral particles are 27 to 34 nanometers in diameter, are non-enveloped and contain a single-strand of positive-sense RNA that is approximately 7200 bases in length, polyadenylated at the 3' terminus, and capped at the 5'terminus.[3][4][5]

The genome of HEV contains 3 Open Reading Frames:

  • ORF1 - contains functional motifs and non-structural protein domains, including:[3]
  • ORF2 - contains de protein of the viral capsid, responsible for:
  • Viral assembly[6]
  • Target cell interaction[7]
  • Immunogenicity[8]

Life Cycle

Genotypes

Tropism

Natural Reservoir

The natural reservoir of HEV is yet to be identified. Different observations have suggested different reservoirs:

  • Prolonged fecal shedding from patients with history of the disease has been suggested. However, the duration of viral shedding in feces is not compatible with this hypothesis.[11]
  • Environmental reservoir was suggested following detection of HEV in sewages.[12]
  • Continuous fecal shedding from asymptomatic patients was suggested as a form of maintenance of the virus, contaminating water supplies.[13]
  • The existence of an animal reservoir is supported by the detection of anti-HEV antibodies in different species.[13]

References

  1. "Hepatitis E virus taxonomy".
  2. "http://phil.cdc.gov/phil/details.asp". External link in |title= (help)
  3. 3.0 3.1 Kamar N, Bendall R, Legrand-Abravanel F, Xia NS, Ijaz S, Izopet J; et al. (2012). "Hepatitis E." Lancet. 379 (9835): 2477–88. doi:10.1016/S0140-6736(11)61849-7. PMID 22549046.
  4. Reyes GR, Purdy MA, Kim JP, Luk KC, Young LM, Fry KE; et al. (1990). "Isolation of a cDNA from the virus responsible for enterically transmitted non-A, non-B hepatitis". Science. 247 (4948): 1335–9. PMID 2107574.
  5. Tam AW, Smith MM, Guerra ME, Huang CC, Bradley DW, Fry KE; et al. (1991). "Hepatitis E virus (HEV): molecular cloning and sequencing of the full-length viral genome". Virology. 185 (1): 120–31. PMID 1926770.
  6. Li TC, Yamakawa Y, Suzuki K, Tatsumi M, Razak MA, Uchida T; et al. (1997). "Expression and self-assembly of empty virus-like particles of hepatitis E virus". J Virol. 71 (10): 7207–13. PMC 192060. PMID 9311793.
  7. Kalia M, Chandra V, Rahman SA, Sehgal D, Jameel S (2009). "Heparan sulfate proteoglycans are required for cellular binding of the hepatitis E virus ORF2 capsid protein and for viral infection". J Virol. 83 (24): 12714–24. doi:10.1128/JVI.00717-09. PMC 2786843. PMID 19812150.
  8. Xing L, Wang JC, Li TC, Yasutomi Y, Lara J, Khudyakov Y; et al. (2011). "Spatial configuration of hepatitis E virus antigenic domain". J Virol. 85 (2): 1117–24. doi:10.1128/JVI.00657-10. PMC 3020005. PMID 21068233.
  9. Yamada K, Takahashi M, Hoshino Y, Takahashi H, Ichiyama K, Nagashima S; et al. (2009). "ORF3 protein of hepatitis E virus is essential for virion release from infected cells". J Gen Virol. 90 (Pt 8): 1880–91. doi:10.1099/vir.0.010561-0. PMID 19339479.
  10. Emerson SU, Nguyen HT, Torian U, Burke D, Engle R, Purcell RH (2010). "Release of genotype 1 hepatitis E virus from cultured hepatoma and polarized intestinal cells depends on open reading frame 3 protein and requires an intact PXXP motif". J Virol. 84 (18): 9059–69. doi:10.1128/JVI.00593-10. PMC 2937629. PMID 20610720.
  11. Aggarwal R, Kini D, Sofat S, Naik SR, Krawczynski K (2000). "Duration of viraemia and faecal viral excretion in acute hepatitis E." Lancet. 356 (9235): 1081–2. doi:10.1016/S0140-6736(00)02737-9. PMID 11009149.
  12. Ippagunta SK, Naik S, Sharma B, Aggarwal R (2007). "Presence of hepatitis E virus in sewage in Northern India: frequency and seasonal pattern". J Med Virol. 79 (12): 1827–31. doi:10.1002/jmv.21017. PMID 17935174.
  13. 13.0 13.1 Aggarwal R, Jameel S (2011). "Hepatitis E." Hepatology. 54 (6): 2218–26. doi:10.1002/hep.24674. PMID 21932388.