Rat hepatitis E virus: Geographical clustering within Germany and serological detection in wild Norway rats (Rattus norvegicus)

• Published in: Infection, genetics and evolution genetics and evolution, 2012-07, Vol.12 (5), p.947-956
• Main Authors: Johne, Reimar, Dremsek, Paul, Kindler, Eveline, Schielke, Anika, Plenge-Bönig, Anita, Gregersen, Henrike, Wessels, Ute, Schmidt, Katja, Rietschel, Wolfram, Groschup, Martin H., Guenther, Sebastian, Heckel, Gerald, Ulrich, Rainer G.
• Format: Article
• Language: English
• Subjects: amino acid sequences; Animals; Animals, Wild - virology; antibodies; antigens; Biological and medical sciences; birds; Capsid Proteins - immunology; cities; Cluster Analysis; coat proteins; deer; disease reservoirs; Epidemiology. Vaccinations; Female; General aspects; genome; Genome, Viral - genetics; genotype; Germany - epidemiology; Hepatitis Antibodies - blood; Hepatitis Antibodies - immunology; Hepatitis Antigens - genetics; Hepatitis Antigens - immunology; Hepatitis E - epidemiology; Hepatitis E - immunology; Hepatitis E - veterinary; Hepatitis E - virology; Hepatitis E virus; Hepatitis E virus - classification; Hepatitis E virus - genetics; Hepatitis E virus - immunology; Hepatitis E virus - isolation & purification; humans; industrialization; Infectious diseases; Kilham rat virus; Liver - immunology; Liver - virology; Medical sciences; Molecular Epidemiology; open reading frames; Phylogeny; Pleural Cavity - immunology; Pleural Cavity - virology; Polymerase Chain Reaction; Rats; Rats, Wistar; Rattus norvegicus; Recombinant Proteins - genetics; Recombinant Proteins - immunology; RNA; RNA, Viral - analysis; RNA, Viral - blood; RT-PCR; Serologic Tests; serological surveys; Serology; swine; Viral Proteins - genetics; Viral Proteins - immunology; wild boars; Zoonoses
• ISSN: 1567-1348; 1567-7257
• DOI: 10.1016/j.meegid.2012.02.021

► Detection of ratHEV-specific RNA and antibodies in Norway rats from four cities in Germany. ► Genome analysis of novel ratHEV strains indicates a geographical clustering of sequences. ► Continuing existence of ratHEV in the rat populations. ► High amount of Norway rats showing exclusively ratHEV RNA or anti-ratHEV antibodies. ► Antigenic differences between recombinant capsid protein derivatives of ratHEV and genotype 3. Zoonotic hepatitis E virus (HEV) infection in industrialised countries is thought to be caused by transmission from wild boar, domestic pig and deer as reservoir hosts. The detection of HEV-specific antibodies in rats and other rodents has suggested that these animals may represent an additional source for HEV transmission to human. Recently, a novel HEV (ratHEV) was detected in Norway rats from Hamburg, Germany, showing the typical genome organisation but a high nucleotide and amino acid sequence divergence to other mammalian and to avian HEV strains. Here we describe the multiple detection of ratHEV RNA and HEV-specific antibodies in Norway rats from additional cities in north-east and south-west Germany. The complete genome analysis of two novel strains from Berlin and Stuttgart confirmed the association of ratHEV to Norway rats. The present data indicated a continuing existence of this virus in the rat populations from Berlin and Hamburg. The phylogenetic analysis of a short segment of the open reading frame 1 confirmed a geographical clustering of the corresponding sequences. Serological investigations using recombinant ratHEV and genotype 3 capsid protein derivatives demonstrated antigenic differences which might be caused by the high amino acid sequence divergence in the immunodominant region. The high amount of animals showing exclusively ratHEV RNA or anti-ratHEV antibodies suggested a non-persistent infection in the Norway rat. Future studies have to prove the transmission routes of the virus in rat populations and its zoonotic potential. The recombinant ratHEV antigen generated here will allow future seroepidemiological studies to differentiate ratHEV and genotype 3 infections in humans and animals.