GB virus C/Hepatitis G virus and other putative hepatitis non A-E viruses

Pinho, João Renato Rebello; Silva, Luiz Caetano da

doi:10.1590/S0036-46651996000600010

Abstracts

The identification of the major agents causing human hepatitis (Hepatitis A, B, C, D and E Viruses) was achieved during the last 30 years. These viruses are responsible for the vast majority of human viral hepatitis cases, but there are still some cases epidemiologically related to infectious agents without any evidence of infection with known virus, designated as hepatitis non A - E. Those cases are considered to be associated with at least three different viruses: 1 - Hepatitis B Virus mutants expressing its surface antigen (HBsAg) with altered epitopes or in low quantities; 2 - Another virus probably associated with enteral transmitted non A-E hepatitis, called Hepatitis F Virus. Still more studies are necessary to better characterize this agent; 3 - Hepatitis G Virus or GB virus C, recently identified throughout the world (including Brazil) as a Flavivirus responsible for about 10% of parenteral transmitted hepatitis non A-E. Probably still other unknown viruses are responsible for human hepatitis cases without evidence of infection by any of these viruses, that could be called as non A-G hepatitis.

hepatitis G; hepatitis F; GBV-C; HGV; HFV; non A-E hepatitis; HBV mutants

A identificação dos virus responsáveis pela vasta maioria dos casos de hepatite (Vírus das Hepatites A, B, C, D e E) foi realizada durante os últimos 30 anos. Entretanto, existem ainda alguns casos epidemiologicamente relacionados com agentes infecciosos, nos quais não se encontra nenhuma evidência de infecção por nenhum vírus conhecido. Estes casos foram designados de Hepatites não A-E e são atualmente relacionados com pelo menos três diferentes vírus: 1 - Mutantes do Vírus da Hepatite B, que expressam o antígeno de superfície (AgHBs) com epitopos alterados ou em baixas concentrações. 2 - Um outro vírus, denominado Vírus da Hepatite F, foi associado com as hepatites não A-E de transmissão entérica. Entretanto, maiores estudos são ainda necessários para sua melhor caracterização. 3 - O Vírus da Hepatite G ou Vírus GB-C foi recentemente identificado em diferentes regiões do mundo (incluindo o Brasil) como um Flavi-vírus responsável por cerca de 10% dos casos de hepatites não A-E de transmissão parenteral. Provavelmente, ainda outros vírus responsáveis pelas hepatites humanas serão encontrados em casos de hepatites sem marcadores de infecção por nenhum destes vírus.

INVITED REVIEW

GB virus C/Hepatitis G virus and other putative hepatitis non A-E viruses

O vírus da Hepatite G e outros possíveis vírus causadores de hepatites não-A, não-E

João Renato Rebello Pinho^I; Luiz Caetano da Silva^II

^IServiço de Virologia do Instituto Adolfo Lutz

^IIInstituto de Medicina Tropical da Universidade de São Paulo, São Paulo, SP, Brasil

^{Correspondence to} Correspondence to: Dr. João Renato Rebello Pinho Serviço de Virologia, Instituto Adolfo Lutz Av. Dr. Arnaldo 355 01246-902 São Paulo, SP, Brasil

SUMMARY

The identification of the major agents causing human hepatitis (Hepatitis A, B, C, D and E Viruses) was achieved during the last 30 years. These viruses are responsible for the vast majority of human viral hepatitis cases, but there are still some cases epidemiologically related to infectious agents without any evidence of infection with known virus, designated as hepatitis non A - E. Those cases are considered to be associated with at least three different viruses: 1 - Hepatitis B Virus mutants expressing its surface antigen (HBsAg) with altered epitopes or in low quantities; 2 - Another virus probably associated with enteral transmitted non A-E hepatitis, called Hepatitis F Virus. Still more studies are necessary to better characterize this agent; 3 - Hepatitis G Virus or GB virus C, recently identified throughout the world (including Brazil) as a Flavivirus responsible for about 10% of parenteral transmitted hepatitis non A-E. Probably still other unknown viruses are responsible for human hepatitis cases without evidence of infection by any of these viruses, that could be called as non A-G hepatitis.

Keywords: hepatitis G; hepatitis F; GBV-C; HGV; HFV; non A-E hepatitis; HBV mutants.

RESUMO

A identificação dos virus responsáveis pela vasta maioria dos casos de hepatite (Vírus das Hepatites A, B, C, D e E) foi realizada durante os últimos 30 anos. Entretanto, existem ainda alguns casos epidemiologicamente relacionados com agentes infecciosos, nos quais não se encontra nenhuma evidência de infecção por nenhum vírus conhecido. Estes casos foram designados de Hepatites não A-E e são atualmente relacionados com pelo menos três diferentes vírus: 1 - Mutantes do Vírus da Hepatite B, que expressam o antígeno de superfície (AgHBs) com epitopos alterados ou em baixas concentrações. 2 - Um outro vírus, denominado Vírus da Hepatite F, foi associado com as hepatites não A-E de transmissão entérica. Entretanto, maiores estudos são ainda necessários para sua melhor caracterização. 3 - O Vírus da Hepatite G ou Vírus GB-C foi recentemente identificado em diferentes regiões do mundo (incluindo o Brasil) como um Flavi-vírus responsável por cerca de 10% dos casos de hepatites não A-E de transmissão parenteral. Provavelmente, ainda outros vírus responsáveis pelas hepatites humanas serão encontrados em casos de hepatites sem marcadores de infecção por nenhum destes vírus.

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Correspondence to:

Dr. João Renato Rebello Pinho

Serviço de Virologia, Instituto Adolfo Lutz

Av. Dr. Arnaldo 355

01246-902 São Paulo, SP, Brasil

Publication Dates

Publication in this collection
22 Sept 2006
Date of issue
Dec 1996

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] 1. AIKAWA, T.; SUGAI, Y. & OKAMOTO, H. - Hepatitis G infection in drug abusers with chronic hepatitis C. New Engl. J. Med., 334: 195-196, 1996.

[2] 2. ALMEIDA, J.D.; DEINHARDT, F.; HOLMES, A.W. et al. - Morphology of the GB hepatitis agent. Nature (Lond.), 261: 608-609, 1976.

[3] 3. ALTER, H.J.; HOLLAND, P. V.; MORROW, A.G. et at. - Clinical and serological analysis of transfusion-associated hepatitis. Lancet, 2: 838-841, 1975.

[4] 4. ALTER, H.J. & BRADLEY, D.W. - Non-A, non-B hepatitis unrelated to the hepatitis C virus (Non-ABC). Semin. Liver Dis., 15: 110-120, 1995.

[5] 5. ALTER, H.J. - Cloning and clinical implications of Hepatits G virus. New Engl. J. Med., 334: 1536-1537, 1996.

[6] 6. ARANKALLE, V.A.; CHADHA, M.S.; TSAREV, S.A. et al. - Seroepidemiology of water- borne hepatitis in India and evidence for a third enterically-transmitted hepatitis agent. Proc. nat. Acad. Sci. (Wash.), 91: 1428-1432, 1994.

[7] 7. BLUMBERG, B.S.; ALTER, H.J. & VISNICH, S. - A "new" antigen in leukemia sera. J. Amer. med. Ass., 191: 541-546, 1965.

[8] 8. BRADLEY, D.W.; MAYNARD, J.E.; POPPER, H. et al. - Posttransfusion non-A, non-B hepatitis: physicochemical properties of two distinct agents. J. infect. Dis., 148: 254-265, 1983.

[9] 9. BYRNES, J.J.; BANKS, T.; PIATACK, M. et al. - Hepatitis G associated aplastic anaemia. Lancet, 348: 472, 1996.

[10] 10. CARMAN, W.F.; ZANETTI, A.R.; KARAYIANNIS, P. et al. - Vaccine-induced escape mutant of hepatitis B virus. Lancet, 336: 325-329, 1990.

[11] 11. CARMAN, W.F.; KORULA, J.; WALLACE, L. et al. - Fulminant reactivation of hepatitis B due to envelope protein mutant that escaped detection by monoclonal HBsAg ELISA. Lancet, 345: 1406-1407, 1995.

[12] 12. CHAZOUILLČRES, O.; MAMISH, D.; LIM, M. et al. - Occult hepatitis B virus as source of infection in liver transplant recipients. Lancet, 343: 142-146, 1994.

[13] 13. CHOO, Q.L.; KUO,G.; WEINER, A.J. et al. - Isolation of a cDNA clone derived from a blood-borne non-A, non-B viral hepatitis genome. Science, 244: 359-362, 1989.

[14] 14. DEINHARDT, F.; HOLMES, A.W.; CAPPS, R.B. et al. - Studies on the transmission of human viral hepatitis to marmoset monkeys. I. Transmission of disease, serial passages and description of liver lesions. J. exp. Med., 125: 673-678, 1967.

[15] 15. DEINHARDT, F.; PETERSON, D.; CROSS, G. et al. - Hepatitis in marmosets. Amer.J. med. Sci., 270: 73-80, 1975.

[16] 16. DE LAMBALLERIE, X.; CHARREL, R.N. & DUSSOL, B. - Hepatitis GB virus C in patients on hemodialysis. New Engl. J. Med., 334: 1549, 1996.

[17] 17. DEKA, N.; SHARMA, M.D. & MUKERJEE, R. - Isolation of the novel agent from human stool samples that is associated with sporadic non-A, non-B hepatitis. J. Virol., 68: 7810-7815, 1994.

[18] 18. DIENSTAG, J.L.; WAGNER, J.A.; PURCELL, R.H. et al. - Virus-like particles and GB agent hepatitis. Nature (Lond.), 264: 260-261, 1976.

[19] 19. EDITORIAL - Hepatitis G? Lancet, 337: 1070, 1991.

[20] 20. EGAWA, K.; YUKAWA, T. & ARAKAWA, S. - Infection with GB virus C in leprous patients in Japan. J. med. Virol.,49: 110-114, 1996.

[21] 21. FARCI, P.; ALTER, H.J.; GOVINDARAJAN, S. et al. - Lack of protective immunity against reinfection with hepatitis C virus. Science, 258: 135-150, 1992.

[22] 22. FEINSTONE, S.M.; KAPIKIAN, A.Z. & PURCELL, R.H. - Hepatitis A: detection by immune electron microscopy of a viruslike antigen associated with acute illness. Science, 182: 1026-1028, 1973.

[23] 23. FEINSTONE, S.M.; KAPIKIAN, A.Z.; PURCELL, R.H. et al. - Transfusion-associated hepatitis not due to viral hepatitis type A or B. New Engl. J. Med., 292: 767-770, 1975.

[24] 24. FEITELSON, M.; LEGA, L.; GUO, J. et al. - Pathogenesis of post transfusion viral hepatitis in children with beta - thalassemia. Hepatology, 19: 558-568, 1994.

[25] 25. FEITELSON, M.A.; DUAN, L.X.; GUO, J et al. - X region deletion variants of hepatitis B virus in surface antigen - negative infections and non-A, non-B hepatitis. J. infect. Dis., 172: 713-722, 1995.

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