While performing a nationwide survey of hepatitis E virus (HEV) infection among 450 wild boars () that had been captured in Japan between November 2005 and March 2010, we found 16 boars (3.6 %) with ongoing HEV infection: 11 had genotype 3 HEV, four had genotype 4 HEV and the remaining boar was infected with HEV of an unrecognized genotype (designated wbJOY_06). The entire wbJOY_06 genome was sequenced and was found to comprise 7246 nt excluding the poly(A) tail. The wbJOY_06 isolate was highly divergent from known genotype 1–4 HEV isolates derived from humans, swine, wild boars, deer, mongoose and rabbits (=145) by 22.6–27.7 %, rat HEV isolates (=2) by 46.0–46.2 %, and avian HEV isolates (=5) by 52.5–53.1 % over the entire genome. A Simplot analysis revealed no significant recombination between the existing HEV strains of genotypes 1–4. Therefore, we propose that the wbJOY_06 isolate is the first member of a previously unidentified genotype.


Article metrics loading...

Loading full text...

Full text loading...



  1. Chandler, J. D., Riddell, M. A., Li, F., Love, R. J. & Anderson, D. A.(1999). Serological evidence for swine hepatitis E virus infection in Australian pig herds. Vet Microbiol 68, 95–105.[CrossRef] [Google Scholar]
  2. Chen, S. H., Su, S. Y., Lo, C. Z., Chen, K. H., Huang, T. J., Kuo, B. H. & Lin, C. Y.(2009). PALM: a paralleled and integrated framework for phylogenetic inference with automatic likelihood model selectors. PLoS ONE 4, e8116.[CrossRef] [Google Scholar]
  3. Colson, P., Borentain, P., Queyriaux, B., Kaba, M., Moal, V., Gallian, P., Heyries, L., Raoult, D. & Gerolami, R.(2010). Pig liver sausage as a source of hepatitis E virus transmission to humans. J Infect Dis 202, 825–834.[CrossRef] [Google Scholar]
  4. Dalton, H. R., Bendall, R., Ijaz, S. & Banks, M.(2008). Hepatitis E: an emerging infection in developed countries. Lancet Infect Dis 8, 698–709.[CrossRef] [Google Scholar]
  5. de Deus, N., Peralta, B., Pina, S., Allepuz, A., Mateu, E., Vidal, D., Ruiz-Fons, F., Martín, M., Gortázar, C. & Segalés, J.(2008). Epidemiological study of hepatitis E virus infection in European wild boars (Sus scrofa) in Spain. Vet Microbiol 129, 163–170.[CrossRef] [Google Scholar]
  6. Emerson, S. U., Anderson, D., Arankalle, A., Meng, X. J., Purdy, M., Schlauder, G. G. & Tsarev, S. A.(2005). Hepevirus. In Virus Taxonomy: Eighth Report of the International Committee on Taxonomy of Viruses, pp. 853–857. Edited by Fauquet, C. M., Mayo, M. A., Maniloff, J., Desselberger, U. & Ball, L. A.. London. : Elsevier/Academic Press. [Google Scholar]
  7. Emerson, S. U., Nguyen, H. T., Torian, U., Burke, D., Engle, R. & Purcell, R. H.(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, 9059–9069.[CrossRef] [Google Scholar]
  8. Felsenstein, J.(1985). Confidence limits on phylogenies: an approach using the bootstrap. Evolution 39, 783–791.[CrossRef] [Google Scholar]
  9. Graff, J., Nguyen, H., Yu, C., Elkins, W. R., St Claire, M., Purcell, R. H. & Emerson, S. U.(2005). The open reading frame 3 gene of hepatitis E virus contains a cis-reactive element and encodes a protein required for infection of macaques. J Virol 79, 6680–6689.[CrossRef] [Google Scholar]
  10. Graff, J., Torian, U., Nguyen, H. & Emerson, S. U.(2006). A bicistronic subgenomic mRNA encodes both the ORF2 and ORF3 proteins of hepatitis E virus. J Virol 80, 5919–5926.[CrossRef] [Google Scholar]
  11. Guindon, S. & Gascuel, O.(2003). A simple, fast, and accurate algorithm to estimate large phylogenies by maximum likelihood. Syst Biol 52, 696–704.[CrossRef] [Google Scholar]
  12. Haqshenas, G., Shivaprasad, H. L., Woolcock, P. R., Read, D. H. & Meng, X. J.(2001). Genetic identification and characterization of a novel virus related to human hepatitis E virus from chickens with hepatitis-splenomegaly syndrome in the United States. J Gen Virol 82, 2449–2462. [Google Scholar]
  13. Huang, Y. W., Opriessnig, T., Halbur, P. G. & Meng, X. J.(2007). Initiation at the third in-frame AUG codon of open reading frame 3 of the hepatitis E virus is essential for viral infectivity in vivo. J Virol 81, 3018–3026.[CrossRef] [Google Scholar]
  14. Ichiyama, K., Yamada, K., Tanaka, T., Nagashima, S., Jirintai, Takahashi, M. & Okamoto, H.(2009). Determination of the 5′-terminal sequence of subgenomic RNA of hepatitis E virus strains in cultured cells. Arch Virol 154, 1945–1951.[CrossRef] [Google Scholar]
  15. Johne, R., Plenge-Bönig, A., Hess, M., Ulrich, R. G., Reetz, J. & Schielke, A.(2010). Detection of a novel hepatitis E-like virus in faeces of wild rats using a nested broad-spectrum RT-PCR. J Gen Virol 91, 750–758.[CrossRef] [Google Scholar]
  16. Kabrane-Lazizi, Y., Meng, X. J., Purcell, R. H. & Emerson, S. U.(1999). Evidence that the genomic RNA of hepatitis E virus is capped. J Virol 73, 8848–8850. [Google Scholar]
  17. Kaci, S., Nöckler, K. & Johne, R.(2008). Detection of hepatitis E virus in archived German wild boar serum samples. Vet Microbiol 128, 380–385.[CrossRef] [Google Scholar]
  18. Lole, K. S., Bollinger, R. C., Paranjape, R. S., Gadkari, D., Kulkarni, S. S., Novak, N. G., Ingersoll, R., Sheppard, H. W. & Ray, S. C.(1999). Full-length human immunodeficiency virus type 1 genomes from subtype C-infected seroconverters in India, with evidence of intersubtype recombination. J Virol 73, 152–160. [Google Scholar]
  19. Lu, L., Li, C. & Hagedorn, C. H.(2006). Phylogenetic analysis of global hepatitis E virus sequences: genetic diversity, subtypes and zoonosis. Rev Med Virol 16, 5–36.[CrossRef] [Google Scholar]
  20. Martelli, F., Caprioli, A., Zengarini, M., Marata, A., Fiegna, C., Di Bartolo, I., Ruggeri, F. M., Delogu, M. & Ostanello, F.(2008). Detection of hepatitis E virus (HEV) in a demographic managed wild boar (Sus scrofa scrofa) population in Italy. Vet Microbiol 126, 74–81.[CrossRef] [Google Scholar]
  21. Matsuda, H., Okada, K., Takahashi, K. & Mishiro, S.(2003). Severe hepatitis E virus infection after ingestion of uncooked liver from a wild boar. J Infect Dis 188, 944.[CrossRef] [Google Scholar]
  22. Meng, X. J.(2010). Hepatitis E virus: animal reservoirs and zoonotic risk. Vet Microbiol 140, 256–265.[CrossRef] [Google Scholar]
  23. Meng, X. J., Purcell, R. H., Halbur, P. G., Lehman, J. R., Webb, D. M., Tsareva, T. S., Haynes, J. S., Thacker, B. J. & Emerson, S. U.(1997). A novel virus in swine is closely related to the human hepatitis E virus. Proc Natl Acad Sci U S A 94, 9860–9865.[CrossRef] [Google Scholar]
  24. Michitaka, K., Takahashi, K., Furukawa, S., Inoue, G., Hiasa, Y., Horiike, N., Onji, M., Abe, N. & Mishiro, S.(2007). Prevalence of hepatitis E virus among wild boar in the Ehime area of western Japan. Hepatol Res 37, 214–220.[CrossRef] [Google Scholar]
  25. Nakamura, M., Takahashi, K., Taira, K., Taira, M., Ohno, A., Sakugawa, H., Arai, M. & Mishiro, S.(2006). Hepatitis E virus infection in wild mongooses of Okinawa, Japan: demonstration of anti-HEV antibodies and a full-genome nucleotide sequence. Hepatol Res 34, 137–140.[CrossRef] [Google Scholar]
  26. Nishizawa, T., Takahashi, M., Endo, K., Fujiwara, S., Sakuma, N., Kawazuma, F., Sakamoto, H., Sato, Y., Bando, M. & Okamoto, H.(2005). Analysis of the full-length genome of hepatitis E virus isolates obtained from wild boars in Japan. J Gen Virol 86, 3321–3326.[CrossRef] [Google Scholar]
  27. Okamoto, H.(2007). Genetic variability and evolution of hepatitis E virus. Virus Res 127, 216–228.[CrossRef] [Google Scholar]
  28. Okamoto, H., Takahashi, M., Nishizawa, T., Fukai, K., Muramatsu, U. & Yoshikawa, A.(2001). Analysis of the complete genome of indigenous swine hepatitis E virus isolated in Japan. Biochem Biophys Res Commun 289, 929–936.[CrossRef] [Google Scholar]
  29. Okamoto, H., Takahashi, M. & Nishizawa, T.(2003). Features of hepatitis E virus infection in Japan. Intern Med 42, 1065–1071.[CrossRef] [Google Scholar]
  30. Pavio, N., Meng, X. J. & Renou, C.(2010). Zoonotic hepatitis E: animal reservoirs and emerging risks. Vet Res 41, 46.[CrossRef] [Google Scholar]
  31. Payne, C. J., Ellis, T. M., Plant, S. L., Gregory, A. R. & Wilcox, G. E.(1999). Sequence data suggests big liver and spleen disease virus (BLSV) is genetically related to hepatitis E virus. Vet Microbiol 68, 119–125.[CrossRef] [Google Scholar]
  32. Posada, D. & Crandall, K. A.(1998).modeltest: testing the model of DNA substitution. Bioinformatics 14, 817–818.[CrossRef] [Google Scholar]
  33. Purcell, R. H. & Emerson, S. U.(2008). Hepatitis E: an emerging awareness of an old disease. J Hepatol 48, 494–503.[CrossRef] [Google Scholar]
  34. Rutjes, S. A., Lodder-Verschoor, F., Lodder, W. J., van der Giessen, J., Reesink, H., Bouwknegt, M. & de Roda Husman, A. M.(2010). Seroprevalence and molecular detection of hepatitis E virus in wild boar and red deer in The Netherlands. J Virol Methods 168, 197–206.[CrossRef] [Google Scholar]
  35. Saitou, N. & Nei, M.(1987). The neighbor-joining method: a new method for reconstructing phylogenetic trees. Mol Biol Evol 4, 406–425. [Google Scholar]
  36. Sonoda, H., Abe, M., Sugimoto, T., Sato, Y., Bando, M., Fukui, E., Mizuo, H., Takahashi, M., Nishizawa, T. & Okamoto, H.(2004). Prevalence of hepatitis E virus (HEV) infection in wild boars and deer and genetic identification of a genotype 3 HEV from a boar in Japan. J Clin Microbiol 42, 5371–5374.[CrossRef] [Google Scholar]
  37. Takahashi, M., Nishizawa, T., Yoshikawa, A., Sato, S., Isoda, N., Ido, K., Sugano, K. & Okamoto, H.(2002). Identification of two distinct genotypes of hepatitis E virus in a Japanese patient with acute hepatitis who had not travelled abroad. J Gen Virol 83, 1931–1940. [Google Scholar]
  38. Takahashi, K., Terada, S., Kokuryu, H., Arai, M. & Mishiro, S.(2010). A wild boar-derived hepatitis E virus isolate presumably representing so far unidentified “genotype 5”. Kanzo 51, 536–538 (in Japanese ).[CrossRef] [Google Scholar]
  39. Tam, A. W., Smith, M. M., Guerra, M. E., Huang, C. C., Bradley, D. W., Fry, K. E. & Reyes, G. R.(1991). Hepatitis E virus (HEV): molecular cloning and sequencing of the full-length viral genome. Virology 185, 120–131.[CrossRef] [Google Scholar]
  40. Tamada, Y., Yano, K., Yatsuhashi, H., Inoue, O., Mawatari, F. & Ishibashi, H.(2004). Consumption of wild boar linked to cases of hepatitis E. J Hepatol 40, 869–870.[CrossRef] [Google Scholar]
  41. Tanaka, T., Takahashi, M., Takahashi, H., Ichiyama, K., Hoshino, Y., Nagashima, S., Mizuo, H. & Okamoto, H.(2009). Development and characterization of a genotype 4 hepatitis E virus cell culture system using a HE-JF5/15F strain recovered from a fulminant hepatitis patient. J Clin Microbiol 47, 1906–1910.[CrossRef] [Google Scholar]
  42. Tei, S., Kitajima, N., Takahashi, K. & Mishiro, S.(2003). Zoonotic transmission of hepatitis E virus from deer to human beings. Lancet 362, 371–373.[CrossRef] [Google Scholar]
  43. Wang, Y., Zhang, H., Ling, R., Li, H. & Harrison, T. J.(2000). The complete sequence of hepatitis E virus genotype 4 reveals an alternative strategy for translation of open reading frames 2 and 3. J Gen Virol 81, 1675–1686. [Google Scholar]
  44. Yamada, K., Takahashi, M., Hoshino, Y., Takahashi, H., Ichiyama, K., Nagashima, S., Tanaka, T. & Okamoto, H.(2009a). ORF3 protein of hepatitis E virus is essential for virion release from infected cells. J Gen Virol 90, 1880–1891.[CrossRef] [Google Scholar]
  45. Yamada, K., Takahashi, M., Hoshino, Y., Takahashi, H., Ichiyama, K., Tanaka, T. & Okamoto, H.(2009b). Construction of an infectious cDNA clone of hepatitis E virus strain JE03-1760F that can propagate efficiently in cultured cells. J Gen Virol 90, 457–462.[CrossRef] [Google Scholar]
  46. Yazaki, Y., Mizuo, H., Takahashi, M., Nishizawa, T., Sasaki, N., Gotanda, Y. & Okamoto, H.(2003). Sporadic acute or fulminant hepatitis E in Hokkaido, Japan, may be food-borne, as suggested by the presence of hepatitis E virus in pig liver as food. J Gen Virol 84, 2351–2357.[CrossRef] [Google Scholar]
  47. Zhao, C., Ma, Z., Harrison, T. J., Feng, R., Zhang, C., Qiao, Z., Fan, J., Ma, H., Li, M. & other authors(2009). A novel genotype of hepatitis E virus prevalent among farmed rabbits in China. J Med Virol 81, 1371–1379.[CrossRef] [Google Scholar]

Data & Media loading...


vol. , part 4, pp. 902 - 908

Complete genome scanning carried out by the Simplot software program

An unrooted phylogenetic tree constructed by the neighbour-joining method

Comparison of the wbJOY_06 isolate of unclassifiable genotype with 152 reported mammalian and avian HEV isolates whose entire or near-entire sequence is known

HEV isolates used for comparative and phylogenetic analyses in the present study [Single PDF file](264 KB)



Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error