Molecular analysis of G3P[6] rotavirus in the Amazon region of Brazil: evidence of reassortment with equine-like strains.

Aim: To perform a molecular analysis of rotavirus A (RVA) G3P[6] strains detected in 2012 and 2017 in the Amazon region of Brazil. Materials & methods: Eighteen RVA G3P[6] strains were collected from children aged under 10 years hospitalized with acute gastroenteritis, and partial sequencing of each segment genome was performed using Sanger sequencing. Results: Phylogenetic analysis showed that all G3P[6] strains had a DS-1-like genotype constellation. Two strains had the highest nucleotide identities with equine-like G3P[6]/G3P[8] genotypes. Several amino acid alterations in VP4 and VP7 neutralizing epitopes of equine-like RVA G3P[6] strains were observed in comparison with vaccine strains. Conclusion: These findings suggest that equine-like RVA G3P[6] strains have been circulating in the Amazon region of Brazil as a result of direct importation, and support natural RVA evolutionary mechanisms.

Characterization of rotavirus possessing a DS-1-like VP3 gene from pigs in Brazil: Evidence for zooanthroponotic transmission.

Porcine group A rotavirus (RVA) strains SUI15A and SUI24A are suggested to have VP3 genes of human origin possessing DS-1-like backbone. The aim of the present study was to analyse the genome of two strains (SUI15A and SUI24A) and understand the evolution of a rare human-like M2 genotype in pigs. On partial genomic analysis, strains SUI24A (G3-P[13]-I5-R1-C1-M2-A8-N1-T7-E1-H1) and SUI15A (G3-P[x]-Ix-R1-C1-M2-Ax-Nx-T7-E1-H1) were found to have VP3 gene RVA different from those of typical porcine RVA strains described in Brazil and worldwide. This genotypic constellation was a novel constellation that has not been reported previously in both humans and pigs. Furthermore, on phylogenetic analysis, VP3 gene of strains appeared to be of human origin. Therefore, suggested to have evidence for human-to-porcine zooanthroponotic transmission.

Molecular epidemiology of human bocavirus in children with acute gastroenteritis from North Region of Brazil.

PURPOSE: Human bocavirus (HBoV) is a DNA virus that is mostly associated with respiratory infections. However, because it has been found in stool samples, it has been suggested that it may be a causative agent for human enteric conditions. This underpins the continuous search for HBoVs, especially after the introduction of the rotavirus vaccine due to acute gastroenteritis cases related to emergent viruses, as HBoVs are more likely to be found in this post-vaccine scenario. Therefore, the aim of this study is to demonstrate the prevalence of HBoV in children aged less than 10 years with acute gastroenteritis in Brazil from November 2011 to November 2012. METHODOLOGY: Stool samples from hospitalized children ≤10 years old who presented symptoms of acute gastroenteritis were analysed for the presence of rotavirus A (RVA) by an enzyme-linked immunosorbent assay (ELISA), and for HBoV DNA by nested PCR. RESULTS: HBoV positivity was detected in 24.0 % (54/225) of samples. Two peaks of HBoV detection were observed in November 2011 and from July to September 2012. Co-infections between HBoV and rotavirus A were identified in 50.0 % (27/54) of specimens. Phylogenetic analysis identified the presence of HBoV-1 (94.8 %), HBoV-2 (2.6 %) and HBoV-3 (2.6 %) species, with only minor variations among them. CONCLUSION: Our findings provide evidence for the circulation of most HBoV genotypes (except HBoV-4) in the North Region of Brazil at a considerable rate and further investigations are necessary to improve our knowledge in the context of HBoV infections and their role in gastrointestinal diseases.

Analysis of a genotype G3P[9] rotavirus a strain that shows evidence of multiple reassortment events between animal and human rotaviruses.

The species A rotaviruses (RVA) are important gastroenteric pathogens that infect humans and animals. RVA genotype G3P[9] has been described in human-animal reassortment events, and the complexity of its hosts motivates the genetic investigation of this strain. Therefore, the aim of this study is to analyse a G3P[9] sample that was detected in a child with acute gastroenteritis. The 1A3739 sample featured the constellation G3P[9]-I18-R3-C3-Mx-A19-N3-T3-E3-H6. The sequence for VP3 gene was not obtained. The phylogeny showed a closer relationship among genes VP7, VP1, NSP3, NSP4, and NSP5 with genes of animal origin, such as chiropter, alpaca, equine, and simian. In addition, the genes VP6 and NSP1 belong to the new genotypes I18 and A19, respectively. The emergence of strains such as these can interfere with the effectiveness of the RVA vaccine, and continuous monitoring is therefore important. Additional studies are needed to determine the evolutionary source and to identify a possible reservoir of RVA in nature.