RESUMEN
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.
Asunto(s)
Proteínas de la Cápside/genética , Infecciones por Rotavirus/transmisión , Rotavirus/clasificación , Porcinos/virología , Animales , Brasil , Haplotipos , Humanos , Filogenia , Rotavirus/genética , Infecciones por Rotavirus/veterinaria , Infecciones por Rotavirus/virología , Enfermedades de los Porcinos/virología , Zoonosis/virologíaRESUMEN
Group A rotaviruses (RVA) are one of the most common causes of severe acute gastroenteritis in infants worldwide. Rotaviruses spread from person to person, mainly by faecalâ»oral transmission. Almost all unvaccinated children may become infected with RVA in the first two years of life. The establishment of an experimental monkey model with RVA is important to evaluate new therapeutic approaches. In this study, we demonstrated viral shedding and viraemia in juvenileâ»adult Macaca fascicularis orally inoculated with Wa RVA prototype. Nine monkeys were inoculated orally: seven animals with human RVA and two control animals with saline solution. During the study, the monkeys were clinically monitored, and faeces and blood samples were tested for RVA infection. In general, the inoculated animals developed an oligosymptomatic infection pattern. The main clinical symptoms observed were diarrhoea in two monkeys for three days, associated with a reduction in plasmatic potassium content. Viral RNA was detected in seven faecal and five sera samples from inoculated animals, suggesting virus replication. Cynomolgus monkeys are susceptible hosts for human Wa RVA infection. When inoculated orally, they presented self-limited diarrhoea associated with presence of RVA infectious particles in faeces. Thus, cynomolgus monkeys may be useful as animal models to evaluate the efficacy of new antiviral approaches.
Asunto(s)
Infecciones por Rotavirus/virología , Rotavirus/fisiología , Animales , Modelos Animales de Enfermedad , Heces/virología , Humanos , Macaca fascicularis , ARN Viral , Rotavirus/clasificación , Infecciones por Rotavirus/sangre , Carga Viral , Replicación Viral , Esparcimiento de VirusRESUMEN
Group A rotaviruses (RVAs) are leading causes of viral diarrhea in children and in the young of many animal species, particularly swine. In the current study, porcine RVAs were found in fecal specimens from symptomatic piglets on 4 farms in Brazil during the years of 2012-2013. Using RT-PCR, Sanger nucleotide sequencing, and phylogenetic analyses, the whole genomes of 12 Brazilian porcine RVA strains were analyzed. Specifically, the full-length open reading frame (ORF) sequences were determined for the NSP2-, NSP3-, and VP6-coding genes, and partial ORF sequences were determined for the VP1-, VP2-, VP3-, VP4-, VP7-, NSP1-, NSP4-, and NSP5/6-coding genes. The results indicate that all 12 strains had an overall porcine-RVA-like backbone with most segments being designated as genotype 1, with the exception of the VP6- and NSP1-coding genes, which were genotypes I5 and A8, respectively. These results add to our growing understanding of porcine RVA genetic diversity and will provide a platform for monitoring the role of animals as genetic reservoirs of emerging human RVAs strains.
Asunto(s)
Genoma Viral , Rotavirus/genética , Rotavirus/aislamiento & purificación , Porcinos/virología , Proteínas Virales/genética , Animales , Brasil , ADN Viral/genética , Heces/virología , Estudios de Asociación Genética , Variación Genética , Genotipo , Sistemas de Lectura Abierta , Filogenia , Rotavirus/clasificación , Alineación de Secuencia , Análisis de Secuencia de ADN , Manejo de EspecímenesRESUMEN
This study aims to: estimate the prevalence of G2P[4] rotaviruses in Brazil between 2001-2011 from patients with acute gastroenteritis; perform phylogenetic analyses of G2P[4] Brazilian strains (from vaccinated and non-vaccinated children) based on VP7 and VP8(∗) encoding genes and analyze the antigenic regions of these proteins comparing with RV1; and assess the full genetic background of eleven selected Brazilian strains. The G2P[4] detection rate among RVA positive samples was 0/157 in 2001, 3/226 (1.3%) in 2002, 0/514 in 2003, 0/651 in 2004, 31/344 (9%)/2005, 112/227 (49%)/2006, 139/211 (66%)/2007, 240/284 (85%)/2008, 66/176 (37.5%)/2009, 367/422 (87%)/2010 and 75/149 (50%)/2011. For the VP7 and VP8(∗) encoding genes, 52 sequences were analyzed and shared up to 99% nucleotide identity with other contemporary G2P[4] strains detected worldwide, grouping into different clusters. Most differences inside antigenic epitopes of VP7 and VP8(∗) have been maintained in the G2P[4] Brazilian strains along the years, and all were present before RV1 introduction. Eleven G2P[4] strains (4-vaccinated/7-non-vaccinated) were completely characterized and possessed the typical DS-1-like genotype constellation (G2-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2) sharing up to 99% of nucleotide identity with contemporary worldwide strains. Reassortments between Brazilian G2P[4] human strains were observed. In conclusion, the data obtained in the current study suggests that implementation of RV1 vaccination might not influence the genetic diversity observed in G2P[4] analyzed strains. Several factors might have contributed to the increased prevalence of this genotype in Brazil since 2005: the introduction of RV1 into the Brazilian National Immunization Program has resulted in a decrease in the relative prevalence of predominant Wa-like RVA strains facilitating the increase of the heterotypic (DS-1-like) RVA strain G2P[4] in the Brazilian population; the genetic diversity found in different geographical regions throughout the years before, and after the introduction of RV1; the long period of low or no circulation of this genotype in Brazil previous to RV1 introduction could have created favorable conditions for the accumulation of immunological susceptible individuals.
Asunto(s)
Genoma Viral , Genotipo , Infecciones por Rotavirus/prevención & control , Infecciones por Rotavirus/virología , Vacunas contra Rotavirus , Rotavirus/genética , Secuencia de Aminoácidos , Brasil/epidemiología , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Evolución Molecular , Variación Genética , Geografía Médica , Humanos , Datos de Secuencia Molecular , Filogenia , Vigilancia de la Población , Prevalencia , Rotavirus/clasificación , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/epidemiología , Vacunas contra Rotavirus/inmunología , Alineación de Secuencia , Análisis Espacio-Temporal , VacunaciónRESUMEN
This study aims to estimate the frequency of group A rotaviruses (RVA) infection with genotypes G3P[8] and G9P[8] in children that suffered from diarrheal disease (DD) between 2001 and 2011 in different Brazilian regions. In addition, the genetic diversity of G3P[8] and G9P[8] RVA strains recovered from vaccinated and non-vaccinated children was assessed. Laboratory-based RVA surveillance included 15,115 cases of DD, and RVA was detected by enzyme immune-assay and/or polyacrylamide gel electrophoresis in 3357 (22%) samples. RVA was genotyped by the semi-nested RT-PCR and among RVA-positive samples, 100 (2.9%) were G3 (63 G3P[8], 32 G3P not typed [NT], and 5 G3P[6]) and 378 (16.2%) were G9 (318 G9P[8], 59 G9P[NT], and 1 G9P[6]). From the G3 and G9 positive samples, 16 and 12, respectively, were obtained from children aged 4-48months vaccinated with the monovalent vaccine (Rotarix®, RV1). Phylogenetic analyses of the VP7 and VP8(∗) encoding genes were performed for 26 G3P[8] and 48 G9P[8] strains. VP8(∗) phylogenetic analysis revealed that all strains analyzed belonged to P[8] lineage III, whereas RV1 belongs to P[8]-I lineage. VP7 analysis revealed that all G3 and G9 strains belonged to G3-lineage III and G9-lineage III. The comparison of the VP7 and VP8(∗) antigenic epitopes regions of Brazilian strains with RV1 strain revealed several amino acid changes. However, no particular differences among Brazilian strains detected before and after vaccine introduction were observed, or among strains detected from vaccinated and non-vaccinated children. Complete genome characterization of four G3P[8] and seven G9P[8] strains revealed a typical conserved human Wa-like genomic constellation. Changes in the genetic diversity of G3P[8] and G9P[8] RVA detected from 2001 to 2011 in Brazil seemed not be related to RV1 introduction in Brazil.
Asunto(s)
Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología , Rotavirus/clasificación , Rotavirus/genética , Antígenos Virales/genética , Brasil/epidemiología , Proteínas de la Cápside/genética , Preescolar , Heces/virología , Humanos , Lactante , Filogenia , Proteínas de Unión al ARN/genética , Vacunas contra Rotavirus , Proteínas no Estructurales Virales/genéticaRESUMEN
Rotavírus é responsável pela ocorrência de diarreia em humanos e em várias espécies animais. Oito pares de oligonucleotídeos iniciadores (primers) foram desenvolvidos e utilizados como estratégia para o sequenciamento do tipo Sanger da região codificadora dos genes NSP1, NSP3 e VP6 com base nas áreas conservadas do genoma dos rotavírus do grupo A de suínos. Um total de 3 amostras previamente triadas como positivas para rotavírus do grupo A, tiveram os respectivos genes amplificados e seqüenciados por estes oligonucleotídeos iniciadores, possibilitando a caracterização das amostras circulantes, cujo conhecimento é essencial para a compreensão da epidemiologia da doença.(AU)
Rotavirus is the causative pathogen of diarrhea in humans and in several animal species. Eight pairs of primers were developed and used for Sanger sequencing of the coding region of the NSP1, NSP3, and VP6 genes based on the conserved regions of the genome of the group A porcine rotavirus. Three samples previously screened as positive for group A rotaviruses were subjected to gene amplification and sequencing to characterize the pathogen. The information generated from this study is crucial for the understanding of the epidemiology of the disease.(AU)
Asunto(s)
Animales , Proteínas no Estructurales Virales/genética , Proteínas Estructurales Virales/genética , Rotavirus , Cartilla de ADN , Porcinos , Reacción en Cadena de la Polimerasa , DiarreaRESUMEN
Rotavírus é responsável pela ocorrência de diarreia em humanos e em várias espécies animais. Oito pares de oligonucleotídeos iniciadores (primers) foram desenvolvidos e utilizados como estratégia para o sequenciamento do tipo Sanger da região codificadora dos genes NSP1, NSP3 e VP6 com base nas áreas conservadas do genoma dos rotavírus do grupo A de suínos. Um total de 3 amostras previamente triadas como positivas para rotavírus do grupo A, tiveram os respectivos genes amplificados e seqüenciados por estes oligonucleotídeos iniciadores, possibilitando a caracterização das amostras circulantes, cujo conhecimento é essencial para a compreensão da epidemiologia da doença.
Rotavirus is the causative pathogen of diarrhea in humans and in several animal species. Eight pairs of primers were developed and used for Sanger sequencing of the coding region of the NSP1, NSP3, and VP6 genes based on the conserved regions of the genome of the group A porcine rotavirus. Three samples previously screened as positive for group A rotaviruses were subjected to gene amplification and sequencing to characterize the pathogen. The information generated from this study is crucial for the understanding of the epidemiology of the disease.
Asunto(s)
Animales , Cartilla de ADN , Proteínas Estructurales Virales/genética , Proteínas no Estructurales Virales/genética , Rotavirus , Diarrea , Reacción en Cadena de la Polimerasa , PorcinosRESUMEN
Viruses are the leading cause for hospitalization due to gastroenteritis worldwide. Group A rotaviruses (RV) are the most prevalent and are assorted in glycoproteins (G) and protease sensitive (P) dual genotypes based on polymorphic genes that encode the external VP7 and VP4 capsid proteins, respectively. Noroviruses (NoV) have increasingly answered by sporadic gastroenteritis. This study aimed to determine the prevalence of NoV and RV in 68 hospitalized children, between July 2004 and November 2006, at a pediatric hospital in Vitória city, state of Espírito Santo, Southeastern Brazil. Nucleic acid was extracted from fecal suspension following the guanidine-silica procedure. Reverse transcriptase-polymerase chain reaction (RT-PCR) and polyacrylamide gel electrophoresis were employed for NoV and RV detection, respectively. RV genotyping was accomplished using RT-PCR followed by heminested multiplex PCR with specific primers for the most prevalent types of G and P. Fecal samples were positive for NoV and RV in 39.7 percent (27/68) and 20.5 percent (14/68), respectively and together were responsible for 60 percent (41/68) of the cases. RV genotypes were: 50 percent G9P[8], 28.7 percent G2P[4], 7.1 percent G1P[8], G2P[8] and G?P[8]. Vomit was a prominent manifestation observed in 92 percent and 85 percent of the NoV and RV cases, respectively. The median hospitalization was 5 and 5.5 days for the patients infected with NoV and RV, respectively. The data showed that NoV prevailed over RV and it also corroborated the emergence of RV G9 genotype followed by G2P[4], reinforcing the need for RV genotype surveillance.