Clostridium

LETTERS

was found to be slightly different from other HEVs and included a putative ORF (ORF4) of 552 nt that overlapped with ORF1 (online Technical Appendix Figure). A similar pattern of genome organization was observed for both FRHEVs. Phylogenetic analysis of the complete genomes clearly showed that FRHEV was separated from genotype 1–4 HEVs and clustered with rat HEV (Figure). Similarphylogenetic clustering was observed when nucleotide and deduced amino acid sequences of ORF1, ORF2, and ORF3 were analyzed separately. The phylogenetic distance between rat HEV and FRHEV is larger than the distance between genotype 1 and genotype 2 HEV. In recent years, an increasing number of sporadic cases of hepatitis E have been reported (1,9). Several observations suggest that autochthonous casesare caused by zoonotic spread of infection from wild or domestic animals (1,3,9). In addition, IgG anti-HEV seropositivity in the United States has been associated with several factors, including having a pet at home (10). Further studies are needed to identify the zoonotic potential of FRHEV.
This study was supported by the European Community Seventh Framework Program (FP7/2007–2013) throughthe project European Management Platform for Emerging and Re-emerging Infectious Disease Entities (European Commission agreement no. 223498) and the VIRGO consortium, funded by the Dutch government, project number FES0908, and by the Netherlands Genomics Initiative, project number 050-060-452.

Author affiliations: Erasmus Medical Center, Rotterdam, the Netherlands (V. Stalin Raj, S.L. Smits, S.D.Pas, L.B.V. Provacia, A.D.M.E. Osterhaus, B.L. Haagmans); Viroclinics Biosciences BV, Rotterdam (S.L. Smits, A.D.M.E. Osterhaus); and Ferret Clinic Brouwhuis, Helmond, the Netherlands (H. Moorman-Roest)
DOI: http://dx.doi.org/10.3201/eid1808.111659

10.

Kuniholm MH, Purcell RH, McQuillan GM, Engle RE, Wasley A, Nelson KE. Epidemiology of hepatitis E virus in the United States: results fromthe third national health and nutrition examination survey, 1988–1994. J Infect Dis. 2009;200:48–56. http://dx.doi.org/10.1086/599319

References
1. Aggarwal R, Jameel S, Hepatitis E. Hepatology. 2011;54:2218–26. http://dx.doi. org/10.1002/hep.24674 2. Boccia D, Guthmann JP, Klovstad H, Hamid N, Tatay M, Ciglenecki I, et al. High mortality associated with an outbreak of hepatitis E amongdisplaced persons in Darfur, Sudan. Clin Infect Dis. 2006;42:1679–84. http://dx.doi. org/10.1086/504322 3. Meng XJ. Hepatitis E virus: animal reservoirs and zoonotic risk. Vet Microbiol. 2010;140:256–65. http://dx.doi. org/10.1016/j.vetmic.2009.03.017 4. Johne R, Heckel G, Plenge-Bönig A, Kindler E, Maresch C, Reetz J. etal. Novel hepatitis E virus genotype in Norway rats, Germany. Emerg Infect Dis.2010;16:1452–5. http://dx.doi. org/10.3201/eid1609.100444 5. Batts W, Yun S, Hedrick R, Winton J. A novel member of the family Hepeviridae from cutthroat trout (Oncorhynchus clarkii). Virus Res. 2011;158:116–23. http://dx.doi.org/10.1016/j.virusres. 2011.03.019 6. Provacia LB, Smits SL, Martina BE, Raj VS, Doel PV, Amerongen GV, et al. Enteric coronavirus in ferrets, the Netherlands. Emerg Infect Dis.2011;17:1570–1. 7. van Leeuwen M, Williams MM, Koraka P, Simon JH, Smits SL, Osterhaus AD. Human picobirnaviruses identified by molecular screening of diarrhea samples. J Clin Microbiol. 2010;48:1787–94. http:// dx.doi.org/10.1128/JCM.02452-09 8. Victoria JG, Kapoor A, Dupuis K, Schnurr DP, Delwart EL. Rapid identification of known and new RNA viruses from animal tissues. PLoS Pathog.2008;4:e1000163. h t t p : / / d x . d o i . o rg / 1 0 . 1 3 7 1 / j o u r n a l . ppat.1000163 9. Rutjes SA, Lodder WJ, Lodder-Verschoor F, van den Berg HH, Vennema H, Duizer E, et al. Sources of hepatitis E virus genotype 3 in the Netherlands. Emerg Infect Dis. 2009;15:381–7. http://dx.doi. org/10.3201/eid1503.071472

Address for correspondence: Albert D.M.E. Osterhaus, Viroscience Lab, Erasmus Medical...