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Abstract: RotaTeq® is a pentavalent rotavirus vaccine that contains five human-bovine reassortant strains (designated G1, G2, G3, G4, and P1) on the backbone of the naturally attenuated tissue culture-adapted parental bovine rotavirus (BRV) strain WC3. The viral genomes of each of the reassortant strains were completely sequenced and compared pairwise and phylogenetically among each other and to human rotavirus (HRV) and BRV reference strains. Reassortants G1, G2, G3, and G4 contained the VP7 gene from their corresponding HRV parent strains, while reassortants G1 and G2 also contained the VP3 gene (genotype M1) from the HRV parent strain. The P1 reassortant contained the VP4 gene from the HRV parent strain and all the other gene segments from the BRV WC3 strain. The human VP7s had a high level of overall amino acid identity (G1: 95–99%, G2: 94–99% G3: 96–100%, G4: 93–99%) when compared to those of representative rotavirus strains of their corresponding G serotypes. The VP4 of the P1 reassortant had a high identity (92–97%) with those of serotype P1A[8] HRV reference strains, while the BRV VP7 showed identities ranging from 91% to 94% to those of serotype G6 HRV strains. Sequence analyses of the BRV or HRV genes confirmed that the fundamental structure of the proteins in the vaccine was similar to those of the HRV and BRV references strains. Sequences analyses showed that RotaTeq® exhibited a high degree of genetic stability as no mutations were identified in the material of each reassortant, which undergoes two rounds of replication cycles in cell culture during the manufacturing process, when compared to the final material used to fill the dosing tubes. The infectivity of each of the reassortant strains of RotaTeq®, like HRV strains, did not require the presence of sialic acid residues on the cell surface. The molecular and biologic characterization of RotaTeq® adds to the significant body of clinical data supporting the consistent efficacy, immunogenicity, and safety of RotaTeq®. [Copyright &y& Elsevier]

Group A rotaviruses are the main cause of severe diarrhoea in humans and animals throughout the world. We report the first description of a clinically apparent infection with a P[14], G3 rotavirus (strain B4106) in a hospitalized 6-year-old child. The VP7 gene of the B4106 strain had the closest sequence similarity (94% and 97% on the nucleotide and amino acid level, respectively) with strain 30/96 (P[14], G3), a lapine rotavirus isolated in an Italian rabbit in 1996 while the VP4 gene had the closest similarity with strain 30/96 on the nucleotide level (96%), and with lapine strains C-11 (P[14], G3) and Alabama (P[14], G3), isolated in the United States in the 1980s on the amino acid level (99%). The host restriction determinant gene NSP4 of B4106 was also most similar to lapine strain Alabama (95% nt identity and 97% aa identity). Phylogenetic analysis showed that the VP4, VP7, and NSP4 genes of the B4106 strain share a common evolutionary lineage with those of lapine rotavirus strains. We therefore hypothesize that a lapine rotavirus was able to cross the host species barrier and caused disease in a new host. The increasing detection of strains in humans that were previously believed to be restricted to animals raises questions whether interspecies transmission of rotaviruses is a common event in nature. [Copyright &y& Elsevier]

Abstract: Rotavirus C (RVC) is a major cause of gastroenteritis in swine. Between December 2009 and October 2011, 7520 porcine samples were analyzed from herds in the US and Canada. RVC RNA was detected in 46% of the tested samples. In very young pigs (≤3 days old) and young piglets (4–20 days old), 78% and 65%, respectively, RVC positive samples were negative for RVA and RVB. RVC RNA was also detected in 10% of tested lung tissues. Additionally, we investigated the porcine RVC molecular diversity by sequencing the VP7 gene segment of 65 specimens, yielding 70 VP7 gene sequences. Based on pairwise identity frequency profiles and phylogenetic analyses, an 85% nucleotide classification cut-off value was calculated using the novel sequence data generated in this study (n=70) and previously published RVC VP7 sequences (n=82), which resulted in the identification of 9 VP7 RVC genotypes, G1 to G9. [Copyright &y& Elsevier]

Abstract: Rotavirus (RV) is an important cause of gastrointestinal disease in animals and humans. In this study, we developed an RT-PCR to detect RV group B (RVB) and characterized the VP7 (G) gene segment detected in porcine samples. One hundred seventy three samples were tested for RV group A (RVA), RVB, and C (RVC) by RT-PCR and examined for RV-like lesion using histopathology. A majority (86.4%) of the samples had mixed RV infections and co-infections of RVA/RVB/RVC were detected at a higher rate (24.3%) than previously reported. RVB was identified in 46.8% of the 173 samples. An adapted VP7 classification was developed using previously published (n=57) and newly sequenced (n=68) RVB strains, resulting in 20 G genotypes based on an 80% nucleotide identity cutoff value. Our results revealed a broad genetic diversity of porcine RVB strains, suggesting RVB has been the cause of common/pre-existing, yet undiagnosed, disease in pigs. [Copyright &y& Elsevier]