Group A rotaviruses (RVAs) are an important cause of diarrhoeal illness in humans, as well as in mammalian and avian animal species. Previous sequence analyses indicated that avian RVAs are related only distantly to mammalian RVAs. Here, the complete genomes of RVA strain 03V0002E10 from turkey (Meleagris gallopavo) and RVA strain 10V0112H5 from pheasant (Phasianus colchicus) were analysed using a combination of 454 deep sequencing and Sanger sequencing technologies. An adenine-rich insertion similar to that found in the chicken RVA strain 02V0002G3, but considerably shorter, was found in the 39 NCR of the NSP1 gene of the pheasant strain. Most genome segments of both strains were related closely to those of avian RVAs. The novel genotype N10 was assigned to the NSP2 gene of the pheasant RVA, which is related most closely to genotype N6 found in avian RVAs. However, this virus contains a VP4 gene of the novel genotype P [37], which is related most closely to RVAs from pigs, dogs and humans. This strain either may represent an avian/mammalian rotavirus reassortant, or it carries an unusual avian rotavirus VP4 gene, thereby broadening the potential genetic and antigenic variability among RVAs. INTRODUCTIONGroup A rotaviruses (RVAs) are aetiological agents of acute gastroenteritis in humans and animals. They cause severe diarrhoea in infants and children, to which are attributed approximately 453 000 childhood deaths annually (Tate et al., 2012). Recently, two attenuated live vaccines have been introduced and are used successfully for prevention of severe rotavirus-induced disease (Yen et al., 2011).Rotaviruses are classified as a genus within the family Reoviridae (Attoui et al., 2012). They are non-enveloped particles containing a genome of 11 segments of dsRNA with monocistronic coding capacity except for segment 11, which may encode two proteins. Based on antigenic and genome sequence properties, five rotavirus groups (A-E) and two tentative groups (F, G) can be distinguished, which also represent the taxonomically defined rotavirus species and tentative species, respectively (Attoui et al., 2012). In addition, the rotavirus NADRV has been described in adults in Asia (Yang et al., 2004). Recently, a classification system into the eight rotavirus species A-H (with NADRV designated rotavirus H) has been proposed, based on genetic data of genome segment 6 (Matthijnssens et al., 2012).Among the rotavirus groups, RVAs have the highest clinical importance among humans and most mammalian species. The antigenic structures of RVAs eliciting neutralizing antibodies are the outer capsid proteins VP7 and VP4, which define the G-and P-types, respectively. Originally, Gand P-serotypes were defined based on antibody reactivity (Hoshino & Kapikian, 2000). Later on, sequence data of the VP7-and VP4-encoding genome segments were used for definition of G-and P-genotypes, leading to the present list of at least 27 different G-types and 35 different P-types in human and animal RVAs (Matthijnssens et al., 2011). Recently, a genotypi...

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Hepatitis E virus (HEV) is an increasingly recognized zoonotic pathogen. Transmission is suspected to occur from infected pigs or wild boars to humans through direct contact, environmental pathways, or contaminated food. However, the physical and chemical stability of HEV is largely unknown, because suitable cell culture methods for infectivity measurement are missing. Here, we developed a titration method using infection of the cell line A549/D3 with HEV genotype 3 strain 47832c and subsequent counting of focus-forming units by immunofluorescence, which allowed HEV infectivity measurements within a 4-logdilution range. Long-term storage of HEV in cell culture medium at different temperatures indicated a phase of rapid virus inactivation, followed by a slower progression of virus inactivation. Infective HEV was detected up to 21 days at 37°C, up to 28 days at room temperature, and until the end of the experiment (56 days) with a 2.7-log decrease of infectious virus at 4°C. Heat treatment for 1 min resulted in moderate decreases of infectivity up to 60°C, 2-to 3.5-log decreases between 65°C and 75°C, and no remaining virus was detected at temperatures of >80°C. Heating for 70°C resulted in a 3.6-log decrease after 1.5 min and the absence of detectable virus (>3.9-log decrease) after 2 min. The data were used to calculate predictive heat inactivation models for HEV. The results may help estimate HEV stability in the environment or food. The established method may be used to study other aspects of HEV stability in the future. IMPORTANCEIn this study, a cell culture method was developed which allows the measurement of hepatitis E virus (HEV) infectivity. Using this system, the stability of HEV at different time-temperature combinations was assessed, and a predictive model was established. The obtained data may help estimate HEV stability in the environment or food, thus enabling an assessment of the relative risks of HEV infection through distinct routes and by distinct types of food in the future. Hepatitis E virus (HEV) is the causative agent of acute hepatitis worldwide (1). Large outbreaks of hepatitis E have been repeatedly described from developing countries in Asia and Africa, e.g., in Nellore, India, with an estimated 23,915 affected persons and an estimated 314 deaths in 2008 (2). In industrial countries, mainly sporadic cases of acute hepatitis E are recognized (3). The numbers of notified hepatitis E cases have significantly increased in several European countries during the last few years (4, 5). In addition, chronic HEV infections in immunocompromised transplant patients constitute an emerging problem (6).There are many different possible transmission pathways of HEV. HEV genotypes 1 and 2 exclusively infect humans and are mainly transmitted by contaminated drinking water (1). In contrast, HEV genotypes 3 and 4 are zoonotic viruses infecting humans and several animal species, like pigs, wild boars, deer, and rabbits (7). Direct transmission by contact with infected animals and foodborne transmis...

Avian rotaviruses (AvRVs) represent a diverse group of intestinal viruses, which are suspected as the cause of several diseases in poultry with symptoms of diarrhoea, growth retardation or runting and stunting syndrome (RSS). To assess the distribution of AvRVs in chickens and turkeys, we have developed specific PCR protocols. These protocols were applied in two field studies investigating faecal samples or intestinal contents of diseased birds derived from several European countries and Bangladesh. In the first study, samples of 166 chickens and 33 turkeys collected between 2005 and 2008 were tested by PAGE and conventional RT-PCR and AvRVs were detected in 46.2%. In detail, 16.1% and 39.2% were positive for AvRVs of groups A or D, respectively. 11.1% of the samples contained both of them and only four samples (2.0%) contained rotaviruses showing a PAGE pattern typical for groups F and G. In the second study, samples from 375 chickens and 18 turkeys collected between 2009 and 2010 were analyzed using a more sensitive group A-specific and a new group D-specific real-time RT-PCR. In this survey, 85.0% were AvRV-positive, 58.8% for group A AvRVs, 65.9% for group D AvRVs and 38.9% for both of them. Although geographical differences exist, the results generally indicate a very high prevalence of group A and D rotaviruses in chicken and turkey flocks with cases of diarrhoea, growth retardation or RSS. The newly developed diagnostic tools will help to investigate the epidemiology and clinical significance of AvRV infections in poultry.

Group A rotaviruses are a leading cause of gastroenteritis in humans and animals. Transmission between mammalian species and humans has been demonstrated repeatedly. Here, the first entire genome sequence (19,064 bp) of a chicken rotavirus, strain Ch-02V0002G3, is presented. A low degree of nucleotide sequence identity with the mammalian group A rotaviruses is evident for all 11 genome segments, whereas a closer relationship to available rotavirus sequences from avian species has been determined. According to a novel rotavirus classification system, new genotypes were proposed and ratified by the Rotavirus Classification Working Group for eight of the Ch-02V0002G3 genome segments, resulting in the genotype constellation G19-P[30]-I11-R6-C6-M7-A16-N6-T8-E10-H8. Due to the low percentages of genome sequence identity, the different genome segment sizes and the marked sequence differences of non-structural proteins, an independent evolution without exchange of genetic material between mammalian and avian group A rotavirus strains is likely.

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Rotaviruses are a leading cause of viral acute gastroenteritis in humans and animals. They are grouped according to gene composition and antigenicity of VP6. Whereas group A, B, and C rotaviruses are found in humans and animals, group D rotaviruses have been exclusively detected in birds. Despite their broad distribution among chickens, no nucleotide sequence data exist so far. Here, the first complete genome sequence of a group D rotavirus (strain 05V0049) is presented, which was amplified using sequence-independent amplification strategies and degenerate primers. Open reading frames encoding homologues of rotavirus proteins VP1 to VP4, VP6, VP7, and NSP1 to NSP5 were identified. Amino acid sequence identities between the group D rotavirus and the group A, B, and C rotaviruses varied between 12.3% and 51.7%, 11.0% and 23.1%, and 9.5% and 46.9%, respectively. Segment 10 of the group D rotavirus has an additional open reading frame. Generally, phylogenetic analysis indicated a common evolution of group A, C, and D rotaviruses, separate from that of group B. However, the NSP4 sequence of group C has only very low identities in comparison with cogent sequences of all other groups. The avian group A NSP1 sequences are more closely related to those of group D than those of mammalian group A rotaviruses. Most interestingly, the nucleotide sequences at the termini of the 11 genome segments are identical between group D and group A rotaviruses. Further investigations should clarify whether these conserved structures allow an exchange of genome segments between group A and group D rotaviruses.Rotaviruses are a major cause of acute gastroenteritis in young children (22,32,54,55). They are also etiological agents of diarrhea in several mammalian and avian species (7,9,10,39,52,65,75). Rotaviruses belong to the family Reoviridae and have a nonenveloped viral capsid containing a genome of 11 double-stranded RNA (dsRNA) segments (21, 62). The outer layer of the virus particle is formed by VP4 and VP7 proteins, which possess neutralization antigens. The intermediate layer consists of VP6, a conserved protein, which defines the rotavirus groups. The inner layer is formed by VP2 surrounding a complex of VP1 and VP3, which represent the RNA-dependent RNA polymerase and the guanylyl transferase, respectively (12, 60), and the viral genomic RNAs. In addition, at least five nonstructural proteins are encoded by the rotavirus genome and have diverse functions, e.g

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