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We report here the whole genomic analyses of two G4P[6] (RVA/Human-wt/CHN/E931/2008/G4P[6], RVA/Human-wt/CHN/R1954/2013/G4P[6]), one G3P[6] (RVA/Human-wt/CHN/R946/2006/G3P[6]) and one G4P[8] (RVA/Human-wt/CHN/E2484/2011/G4P[8]) group A rotavirus (RVA) strains detected in sporadic cases of diarrhea in humans in the city of Wuhan, China. All the four strains displayed a Wa-like genotype constellation. Strains E931 and R1954 shared a G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1 constellation, whilst the 11 gene segments of strains R946 and E2484 were assigned to G3-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1 and G4-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 genotypes, respectively. Phylogenetically, the VP7 gene of R946, NSP3 gene of E931, and 10 of 11 gene segments of E2484 (except for VP7 gene) belonged to lineages of human RVAs. On the other hand, based on available data, it was difficult to ascertain porcine or human origin of VP3 genes of strains E931 and R946, and NSP2 genes of strains R946 and R1954. The remaining genes of E2484, E931, R946 and R1954 were close to those of porcine RVAs from China, and/or porcine-like human RVAs. Taken together, our observations suggested that strain R1954 might have been derived from porcine RVAs, whilst strains R946 and E931 might be reassortants possessing human RVA-like gene segments on a porcine RVA genetic backbone. Strain E2484 might be derived from reassortment events involving acquisition of a porcine-like VP7 gene by a Wa-like human RVA strain. The present study provided important insights into zoonotic transmission and complex reassortment events involving human and porcine RVAs, reiterating the significance of whole-genomic analysis of RVA strains., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Rotaviruses are a major etiologic agent of gastroenteritis in infants and young children worldwide. Since the latter of the 1990s, G3 human rotaviruses referred to as "new variant G3" have emerged and spread in China, being a dominant genotype until 2010, although their genomic evolution has not yet been well investigated., Methods: The complete genomes of 33 G3P[8] human rotavirus strains detected in Wuhan, China, from 2000 through 2013 were analyzed. Phylogenetic trees of concatenated sequences of all the RNA segments and individual genes were constructed together with published rotavirus sequences., Results: Genotypes of 11 gene segments of all the 33 strains were assigned to G3-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, belonging to Wa genogroup. Phylogenetic analysis of the concatenated full genome sequences indicated that all the modern G3P[8] strains were assigned to Cluster 2 containing only one clade of G3P[8] strains in the US detected in the 1970s, which was distinct from Cluster 1 comprising most of old G3P[8] strains. While main lineages of all the 11 gene segments persisted during the study period, different lineages appeared occasionally in RNA segments encoding VP1, VP4, VP6, and NSP1-NSP5, exhibiting various allele constellations. In contrast, only a single lineage was detected for VP7, VP2, and VP3 genes. Remarkable lineage shift was observed for NSP1 gene; lineage A1-2 emerged in 2007 and became dominant in 2008-2009 epidemic season, while lineage A1-1 persisted throughout the study period., Conclusion: Chinese G3P[8] rotavirus strains have evolved since 2000 by intra-genogroup reassortment with co-circulating strains, accumulating more reassorted genes over the years. This is the first large-scale whole genome-based study to assess the long-term evolution of common human rotaviruses (G3P[8]) in an Asian country.

The group A rotavirus (RVA) G3P[9] is a rare VP7-VP4 genotype combination, detected occasionally in humans and cats. Other than the prototype G3P[9] strain, RVA/Human- tc/JPN/AU-l/1982/G3P3[9], the whole genomes of only two human G3P[9] RVA strains and two feline G3P[9] RVA strains have been analyzed so far, revealing complex evolutionary patterns, distinct from that of AU-1. We report here the whole genomic analyses of two human G3P[9] RVA strains, RVA/Human-tc/CHN/L621/2006/G3P[9] and RVA/Human-wt/CHN/E2451/2011/G3P[9], detected in patients with diarrhea in China. Strains L621 and E2451 possessed a H6 NSP5 genotype on an AU-1-like genotype constellation, not reported previously. However, not all the genes of L621 and E2451 were closely related to those of AU-1, or to each other, revealing different evolutionary patterns among the AU-1-like RVAs. The VP7, VP4, VP6 and NSP4 genes of E2451 and L621 were found to cluster together with human G3P[9] RVA strains believed to be of possible feline/canine origin, and feline or raccoon dog RVA strains. The VP1, VP3, NSP2 and NSP5 genes of E2451 and L621 formed distinct clusters in genotypes typically found in feline/canine RVA strains or RVA strains from other host species which are believed to be of feline/canine RVA origin. The VP2 genes of E2451 and L621, and NSP3 gene of L621 clustered among RVA strains from different host species which are believed to have a complete or partial feline/canine RVA origin. The NSP1 genes of E2451 and L621, and NSP3 gene of E2451 clustered with AU-1 and several other strains possessing a complete or partial feline RVA strain BA222-05-like genotype constellation. Taken together, these observations suggest that nearly all the eleven gene segments of G3P[9] RVA strains L621 and E2451 might have originated from feline/canine RVAs, and that reassortments may have occurred among these feline/canine RVA strains, before being transmitted to humans., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Hospital-based surveillance of rotavirus genotypes was conducted in Wuhan, China, between March 2008 and May 2011. The detection rates of group A rotavirus were 24.6% (458/1859) and 12.1% (96/795) in children and adults, respectively, with diarrhea. Among the 554 positive specimens, the most frequent genotype was G3P[8] (57.9%), followed by G1P[8] (29.4%). Compared with previous studies in Wuhan (2000-2008), the relative frequency of G3P[8] has been decreasing year by year, while the predominant genotype G3 shifted to G1 in 2011. In the present study, a rare P[8]b subtype of the VP4 gene (OP354-like P[8]) was identified in nine strains. Full-length sequences of VP7, VP4, VP6 and NSP4 genes of two G9P[8]b strains (RVA/Human-wt/CHN/E1545/2009/G9P[8]b and RVA/Human-wt/CHN/Z1108/2008/G9P[8]b) were determined for phylogenetic analysis. The four genes of these strains were closely related to one another, and the G9-VP7 genes of these strains belonged to lineage III, which contains globally spreading G9 rotaviruses. The full-length sequence of VP4 gene segments of the P[8]b strains in Wuhan clustered with those of P[8]b strains in Vietnam, Russia and Belgium, while they were distinct from those of the OP354 strain from Malawi and Bangladeshi strains. The VP6 and NSP4 genes of two P[8]b strains belonged to the I1 and E1 genotype, respectively, and clustered with those of strains belonging to Wa-like human rotaviruses from various Asian countries. These findings indicate the changing epidemiologic trend of rotavirus genotypes in Wuhan, i.e., the shift of the predominant type from G3 to G1 and the emergence of P[8]b strains genetically related to those distributed in other Asian countries.

During the 2004 surveillance of rotaviruses in Wuhan, China, a G4P[6] rotavirus strain R479 was isolated from a stool specimen collected from a 2-year-old child with diarrhea. The strain R479 had an uncommon subgroup specificity I + II, and analysis of the VP6 gene suggested that it was related to porcine rotaviruses. In the present study, full-length nucleotide sequences of all the RNA segments of R479 were determined and analyzed phylogenetically to identify the origin of individual RNA segments. According to the rotavirus genotyping system based on 11 RNA segments, the genotype of R479 was expressed as G4-P[6]-I5-R1-C1-M1-A1-N1-T7-E1-H1. This genotype includes the porcine-like VP6 genotype (I5) and bovine-like NSP3 genotype (T7). Phylogenetic analysis revealed that R479 genes encoding VP1, VP2, VP3, VP6, VP7, VP8*, NSP1, NSP4, and NSP5 were more closely related to those of porcine rotaviruses than human or other animal rotaviruses. In contrast, it was remarkable that the NSP3 gene of R479 was genetically closely related to only a bovine rotavirus strain UK. The NSP2 gene of R479 was also unique and clustered with only the G5P[8] human strain IAL28 and G3P[24] simian strain TUCH. These results suggested that R479 may be a reassortant virus having the NSP3 gene from a bovine rotavirus in the genetic background of a porcine rotavirus, with an NSP2 gene related to the porcine-human reassortant strain IAL28. To our knowledge, R479 is the first porcine-bovine reassortant rotavirus isolated from a human., ((c) 2010 Wiley-Liss, Inc.)

Prevalence and phylogenetic relatedness of rotaviruses causing diarrheal diseases in children and adults were analyzed in Wuhan, China. During a period between June 2006 and February 2008, group A rotavirus was identified in 24.9% (280/1126) and 7.6% (83/1088) of specimens taken from children and adults, respectively. G3P[8] was the most frequent genotype in both children (66.3%) and adults (62.7%), followed by G1P[8] (20.3% and 26.2%, respectively). G9 was detected in specimens from six children (2.0%) and seven adults (5.6%). The VP7 genes of G3P[8] rotaviruses from children and adults showed extremely high sequence identities to each other (98.9-100%) and also to those of G3 viruses isolated in Wuhan in 2003-2004. In the phylogenetic analysis of the VP7 gene, the G3P[8] rotaviruses in Wuhan were clustered into a single lineage with some G3 viruses, which had been referred to as "the new variant G3" rotaviruses, reported recently in East Asia and Southeast Asia. Similar to G3P[8] rotaviruses, extremely high sequence identities between children and adults were observed for VP7 genes of G1 and G9 rotaviruses. The G9 viruses were clustered in the lineage of globally spreading strains, while G1 viruses were genetically close to those reported previously in China and Japan. These findings indicated the persistence of the variant G3 rotaviruses and spread of G9 rotaviruses derived from the global G9 lineage in Wuhan, and suggested that the rotaviruses were circulating among children and adults, irrelevant to the G types., ((c) 2008 Wiley-Liss, Inc.)