Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
BMC Pediatr ; 19(1): 42, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30704518

RESUMO

BACKGROUND: Brazil introduced the monovalent rotavirus vaccine (Rotarix®) in 2006. This study aimed to assess the epidemiology and genotype distribution of species-A rotavirus (RVA) in Brazil, comparing the pre- and post-vaccination periods. METHODS: Laboratory-based RVA surveillance included 866 municipalities in 22 Brazilian states, over a 21-year period. A total of 16,185 children with diarrheal diseases (DD) aged up to 12 years between 1996 and 2005 (pre-vaccination period, n = 7030) and from 2006 to 2017 (post-vaccination period, n = 9155) were enrolled. RVA was detected using ELISA immune assay and/or polyacrylamide gel electrophoresis and genotyped using nested PCR and/or nucleotide sequencing. RVA-positivity and genotypes detection rates were compared in distinct periods and age groups and Rotarix vaccination status. RESULTS: RVA-positivity in pre- and post-vaccination periods was, respectively: 4-11 months bracket, 33.3% (668/2006) and 16.3% (415/2547) (p <  0.001); 12-24 months, 28.2% (607/2154) and 22.2% (680/3068) (p <  0.001); 25-48 months, 17.4% (215/1235) and 29.4% (505/1720) (p <  0.001). Genotypes distribution in the pre- and post-vaccination periods was, respectively: G1P [8]/G1P[Not Typed], 417/855 (48.8%) and 118/1835 (6.4%) (p <  0.001); G2P [4]/G2P[NT], 47/855 (5.5%) and 838/1835 (45.7%) (p <  0.001); G3P [8]/G3P[NT], 55/855 (6.4%) and 253/1835 (13.8%) (p <  0.001); G9P [8]/G9P[NT], 238/855 (27.8%) and 152/1835 (8.3%) (p <  0.001); G12P [8]/G129P[NT], 0/871 (0%) and 249/1835(13.6%) (p <  0.001). Concerning infants aged 4-11 months, RVA frequency in fully vaccinated and non-vaccinated individuals was 11.9% (125/1052) and 24.5% (58/237) (p <  0.001), respectively. In children aged 12-24 months, RVA detection rate was 18.1% (253/1395) and 29.6% (77/260) (p <  0.001), for the vaccinated and non-vaccinated individuals, respectively (p <  0.001). CONCLUSIONS: RVA infection was significantly less frequent in children aged ≤2 years with DD after implementing vaccination, mainly among vaccinated children. It was also observed a decrease of P [8] circulation and emergence of G2P[4] in 2005, and afterwards in the post-vaccine era, with spreading of G12P[8] in 2014-2015 and of G3P[8] in 2017. Continuous RVA surveillance must be carried out in this scenario.


Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus , Brasil/epidemiologia , Criança , Pré-Escolar , Genótipo , Humanos , Lactente , Estudos Retrospectivos , Rotavirus/classificação , Rotavirus/genética , Infecções por Rotavirus/virologia , Fatores de Tempo , Cobertura Vacinal , Vacinas Atenuadas
2.
J Infect Dis ; 216(2): 220-227, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28838152

RESUMO

Background: The etiology of acute watery diarrhea remains poorly characterized, particularly after rotavirus vaccine introduction. Methods: We performed quantitative polymerase chain reaction for multiple enteropathogens on 878 acute watery diarrheal stools sampled from 14643 episodes captured by surveillance of children <5 years of age during 2013-2014 from 16 countries. We used previously developed models of the association between pathogen quantity and diarrhea to calculate pathogen-specific weighted attributable fractions (AFs). Results: Rotavirus remained the leading etiology (overall weighted AF, 40.3% [95% confidence interval {CI}, 37.6%-44.3%]), though the AF was substantially lower in the Americas (AF, 12.2 [95% CI, 8.9-15.6]), based on samples from a country with universal rotavirus vaccination. Norovirus GII (AF, 6.2 [95% CI, 2.8-9.2]), Cryptosporidium (AF, 5.8 [95% CI, 4.0-7.6]), Shigella (AF, 4.7 [95% CI, 2.8-6.9]), heat-stable enterotoxin-producing Escherichia coli (ST-ETEC) (AF, 4.2 [95% CI, 2.0-6.1]), and adenovirus 40/41 (AF, 4.2 [95% CI, 2.9-5.5]) were also important. In the Africa Region, the rotavirus AF declined from 54.8% (95% CI, 48.3%-61.5%) in rotavirus vaccine age-ineligible children to 20.0% (95% CI, 12.4%-30.4%) in age-eligible children. Conclusions: Rotavirus remained the leading etiology of acute watery diarrhea despite a clear impact of rotavirus vaccine introduction. Norovirus GII, Cryptosporidium, Shigella, ST-ETEC, and adenovirus 40/41 were also important. Prospective surveillance can help identify priorities for further reducing the burden of diarrhea.


Assuntos
Diarreia/epidemiologia , Diarreia/microbiologia , Diarreia/virologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/uso terapêutico , África/epidemiologia , Ásia/epidemiologia , Brasil/epidemiologia , Pré-Escolar , Fezes/microbiologia , Fezes/virologia , Feminino , Saúde Global , Humanos , Lactente , Modelos Logísticos , Masculino , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Organização Mundial da Saúde
3.
J Med Virol ; 87(9): 1480-90, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25982627

RESUMO

Group A rotaviruses (RVA) and noroviruses (NoV) are the leading cause of acute gastroenteritis (AGE) worldwide. Childhood diarrhea deaths and hospital admissions have declined since the introduction of the monovalent (G1P[8]) vaccine (Rotarix(®) [RV1]) in the National Immunization Program in Brazil in 2006. This study aims to investigate the epidemiological profile of NoV and RVA infections from children with AGE in the Northeastern region of Brazil in the post vaccine season. Two-hundred fecal samples collected from children up to 10 years old in Fortaleza, Ceará between 2008-2009 were screened for the presence of RVA and NoV. Positive samples were genotyped and sequenced. The RVA screening revealed 12% prevalence and all RVA strains belonged to G2P[4] genotype. Phylogenetic analysis based on the 11 RVA genome segments sequenced from eight samples revealed a DS-1-like genotype constellation: I2-R2-C2-M2-A2-N2-T2-E2-H2. For NoV screening, the prevalence observed was 17% and the following genotypes were detected: GII.4 (59%), GII.12 (17%), GII.6 (9%), GII.3 (6%), and GII.? (9%). At least four different NoVs genotypes and two RVA G2P[4] variants were identified circulating in the Northeastern region of Brazil. RVA phylogenetic analysis suggests that the RVA G2P[4] strains might have originated from intragenogroup reassortment events. Whether the genetic modifications observed in these contemporary G2P[4] RVA strains may impact the long-term effectiveness of the current vaccination programs remains to be explored. These data reinforce the importance of surveillance for monitoring the emergence of new strains of RVA and NoV and their impact on cases of acute gastroenteritis.


Assuntos
Infecções por Caliciviridae/virologia , Fezes/virologia , Gastroenterite/virologia , Norovirus/genética , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus , Rotavirus/genética , Sequência de Aminoácidos , Brasil/epidemiologia , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , Feminino , Gastroenterite/etiologia , Variação Genética , Genoma Viral , Genótipo , Humanos , Lactente , Masculino , Filogenia , RNA Viral/genética , Infecções por Rotavirus/epidemiologia , Estações do Ano , Análise de Sequência de DNA , Vacinação , Vacinas Atenuadas
4.
J Med Virol ; 86(12): 2065-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25042068

RESUMO

The monitoring of environmental microbial contamination in healthcare facilities may be a valuable tool to determine pathogens transmission in those settings; however, such procedure is limited to bacterial indicators. Viruses are found commonly in those environments and are rarely used for these procedures. The aim of this study was to assess distribution and viability of a human DNA virus on fomites in an Adult Intensive Care Unit of a private hospital in Rio de Janeiro, Brazil. Human adenoviruses (HAdV) were investigated in 141 fomites by scraping the surface area and screening by quantitative PCR (qPCR) using TaqMan® System (Carlsbad, CA). Ten positive samples were selected for virus isolation in A549 and/or HEp2c cell lines. A total of 63 samples (44.7%) were positive and presented viral load ranging from 2.48 × 10(1) to 2.1 × 10(3) genomic copies per millilitre (gc/ml). The viability was demonstrated by integrated cell culture/nested-PCR in 5 out of 10 samples. Nucleotide sequencing confirmed all samples as HAdV and characterized one of them as specie B, serotype 3 (HAdV-3). The results indicate the risk of nosocomial transmission via contaminated fomites and point out the use of HAdV as biomarkers of environmental contamination.


Assuntos
Adenovírus Humanos/isolamento & purificação , Adenovírus Humanos/fisiologia , Fômites/virologia , Hospitais , Viabilidade Microbiana , Adulto , Brasil , Linhagem Celular , Células Epiteliais/virologia , Genótipo , Hepatócitos/virologia , Humanos , Unidades de Terapia Intensiva , Reação em Cadeia da Polimerase em Tempo Real , Sorogrupo , Carga Viral , Cultura de Vírus
5.
Arch Virol ; 159(7): 1827-33, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24493066

RESUMO

Bovine herpesvirus type 5 (BoHV-5) is an etiologic agent of meningoencephalitis in cattle. The aim of this study was to evaluate the antiviral potential of a series of synthetic Mannich bases derived from lawsone and to investigate at which stage of the BoHV-5 replicative cycle the compounds might be acting. The most potent and selective inhibitor exhibited CC50 and EC50 values of 1867 µM ± 8.3 and 3.8 µM ± 1.2, respectively (ACV: 989 µM ± 2 and 166 µM ± 2, respectively).


Assuntos
Antivirais/farmacologia , Herpesvirus Bovino 5/efeitos dos fármacos , Naftoquinonas/farmacologia , Replicação Viral/efeitos dos fármacos , Aciclovir/farmacologia , Animais , Antivirais/química , Linhagem Celular , Cães , Relação Dose-Resposta a Droga , Herpesvirus Bovino 5/fisiologia , Estrutura Molecular , Naftoquinonas/química , Ensaio de Placa Viral
6.
PLOS Glob Public Health ; 3(11): e0001358, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38015834

RESUMO

Rotavirus is the most common pathogen causing pediatric diarrhea and an important cause of morbidity and mortality in low- and middle-income countries. Previous evidence suggests that the introduction of rotavirus vaccines in national immunization schedules resulted in dramatic declines in disease burden but may also be changing the rotavirus genetic landscape and driving the emergence of new genotypes. We report genotype data of more than 16,000 rotavirus isolates from 40 countries participating in the Global Rotavirus Surveillance Network. Data from a convenience sample of children under five years of age hospitalized with acute watery diarrhea who tested positive for rotavirus were included. Country results were weighted by their estimated rotavirus disease burden to estimate regional genotype distributions. Globally, the most frequent genotypes identified after weighting were G1P[8] (31%), G1P[6] (8%) and G3P[8] (8%). Genotypes varied across WHO Regions and between countries that had and had not introduced rotavirus vaccine. G1P[8] was less frequent among African (36 vs 20%) and European (33 vs 8%) countries that had introduced rotavirus vaccines as compared to countries that had not introduced. Our results describe differences in the distribution of the most common rotavirus genotypes in children with diarrhea in low- and middle-income countries. G1P[8] was less frequent in countries that had introduced the rotavirus vaccine while different strains are emerging or re-emerging in different regions.

7.
J Water Health ; 8(3): 438-45, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20375473

RESUMO

Polyomavirus JC (JCPyV) is largely excreted by the human population through the urinary route and has been recognized as a potential viral marker for human waste contamination. This study aims to investigate the dissemination of JCPyV in waste water from a sewage treatment plant (STP) located in Rio de Janeiro, Brazil, and to describe the prevalence of JCPyV subtypes currently present in this population. Raw and treated sewage samples were collected bimonthly during one year, and examined for the presence of JCPyV using nested polymerase chain reaction (nPCR) and quantitative real time PCR (qPCR). JCPyV was detected by nPCR in 96% and 43% of raw and treated sewage samples, respectively. The concentration of JCPyV present in the samples ranged from 1.2x10(3) to 3.2x10(5) and 2.6x10(2) to 6.2x10(3) genome copies per 2 ml of concentrated raw and treated sewage sample, respectively. The strains were characterized and the obtained nucleotide sequences indicated that the detected JCPyV strains clustered with subtypes of East African, West African and European origin. To our knowledge, this is the first study describing the incidence and diversity of JCPyV strains in raw and treated sewage in Brazil.


Assuntos
DNA Viral/análise , Vírus JC/isolamento & purificação , Esgotos/virologia , Microbiologia da Água , Sequência de Bases , Brasil , Monitoramento Ambiental , Humanos , Vírus JC/genética , Filogenia , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Mem Inst Oswaldo Cruz ; 105(8): 1068-72, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21225209

RESUMO

Rotaviruses are important enteric pathogens for humans and animals. Group A rotaviruses (RV-A) are the most common agents of severe gastroenteritis in infants and young children and vaccination is the most effective method to reduce RV-A-associated diseases. G1P[8], the most prevalent RV-A genotype worldwide, is included in the RV-A vaccine Rotarix®. The discrimination between wild-type G1P[8] and vaccine G1P[8] strains is an important topic in the study of RV-A epidemiology to manage outbreaks and to define control measures for vaccinated children. In this study, we developed a novel method to segregate the wild-type and vaccine strains using restriction endonucleases. The dsRNA from the Rotarix® vaccine was sequenced and the NSP3 gene was selected as the target gene. The vaccine strain has a restriction pattern that is different than that of wild-type RV-A G1P[8] isolates after digestion with the restriction endonuclease BspHI. This pattern could be used as a marker for the differentiation of wild-type G1P[8] strains from the vaccine strain.


Assuntos
Fezes/virologia , Vacinas contra Rotavirus/genética , Rotavirus/genética , Enzimas de Restrição do DNA/genética , Genótipo , Humanos , Polimorfismo de Fragmento de Restrição , Rotavirus/isolamento & purificação , Infecções por Rotavirus/virologia , Vacinas Atenuadas/genética
9.
Antivir Ther ; 25(1): 13-20, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31538962

RESUMO

BACKGROUND: Bovine herpesvirus type 5 is an important agent of meningoencephalitis in cattle and has been identified in outbreaks of bovine neurological disease in several Brazilian states. In recent years, oxoquinoline derivatives have become an important focus in antiviral drug research. METHODS: The cytotoxicity and anti BoHV-5RJ42/01 activity of a set of synthetic 4-oxoquinoline derivatives 4a-k were assayed on Madin-Darby Bovine Kidney cell and antiviral activity by plaque reduction assay. RESULTS: The most promising substance (4h) exhibited CC50 and EC50 values of 1,239 µM ±5.5 and 6.0 µM ±1.5, respectively, with an SI =206. Two other compounds 4j (CC50 = 35 µM ±2 and EC50 = 24 µM ±7.0) and 4k (CC50= 55 µM ±2 and EC50 = 24 µM ±5.1) presented similar inhibitory profile and selectivity indexes of 1.4 and 2.9, respectively. The results of the time-of-addition studies revealed expressive reduction of virus production (≥80%) in different stages of virus replication cycle except for compound 4h that slightly inhibited virus yield in the first 2 h post infection, but it showed expressive virus inhibition after this time. CONCLUSIONS: All three compounds slightly interact with the virus on the virucidal assay and they are not able to block virus attachment and penetration. Antiviral effect of oxoquinoline 4h was more prominent than acyclovir which leads us to suggest compound 4h as a promising molecule for further anti-BoHV-5 drug design.


Assuntos
4-Quinolonas/farmacologia , Antivirais/farmacologia , Herpesvirus Bovino 5/efeitos dos fármacos , Animais , Cães , Células Madin Darby de Rim Canino/efeitos dos fármacos , Ensaio de Placa Viral , Inativação de Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
10.
J Virol Methods ; 155(1): 39-43, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18951920

RESUMO

Noroviruses (NoVs) are recognized as the most common agents of outbreaks of food-borne viral gastroenteritis and the efficiency of different methods for detection of NoVs from food matrices have been tested in several laboratories worldwide. The aim of this study was to develop a rapid and sensitive method for recovery of NoVs by using a filtration concentration method followed by PCR amplification for detection of NoVs from cheese and fresh lettuce. Experimentally, a fecal suspension containing different number of NoVs copies was spiked in the food surface and extracted by a direct elution using a Stomacher apparatus. An Ozone-Safe solvent Vertrel XF treatment was included for cheese samples for removing particulate matter. The watery phase was collected and the viral concentration was performed by the adsorption-elution method using negatively charged membranes with inorganic solvents in a Stericup and afterwards ultrafiltered using a Centriprep Concentrator 50 to obtain a final volume of 2ml. RNA isolation was carried out with the QIAamp Viral RNA Mini Kit available commercially and reverse transcription was carried out with a Pd(N6) random primer. Real time quantitative PCR (TaqMan) and qualitative PCR were used for molecular detection of NoVs. The recovery rate of NoVs ranged from 5.2 to 72.3% in lettuce and from 6 to 56.3% in cheese. The results indicate that this method is suitable for detection of NoVs contamination in food and will help establish the cause and source of NoVs outbreaks of food-borne illness.


Assuntos
Queijo/virologia , Contaminação de Alimentos/análise , Lactuca/virologia , Norovirus/isolamento & purificação , Fezes/virologia , Microbiologia de Alimentos , Gastroenterite/virologia , Humanos , Norovirus/genética , Reação em Cadeia da Polimerase/métodos , RNA Viral/análise , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Tempo
11.
Appl Environ Microbiol ; 74(2): 375-82, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18065620

RESUMO

To assess the presence of the four main viruses responsible for human acute gastroenteritis in a hydrographic network impacted by a disordered urbanization process, a 1-year study was performed involving water sample collection from streams in the hydrographic basin surrounding the city of Manaus, Amazonas, Brazil. Thirteen surface water sample collection sites, including different areas of human settlement characterized as urban, rural, and primary forest, located in the Tarumã-Açu, São Raimundo, Educandos, and Puraquequara microbasins, were defined with a global positioning system. At least one virus was detected in 59.6% (31/52) of the water samples analyzed, and rotavirus was the most frequent (44.2%), followed by human adenovirus (30.8%), human astrovirus (15.4%), and norovirus (5.8%). The viral contamination observed mainly in the urban streams reflected the presence of a local high-density population and indicated the gastroenteritis burden from pathogenic viruses in the water, principally due to recreational activities such as bathing. The presence of viral genomes in areas where fecal contamination was not demonstrated by bacterial indicators suggests prolonged virus persistence in aquatic environments and emphasizes the enteric virus group as the most reliable for environmental monitoring.


Assuntos
Gastroenterite/virologia , Rios/virologia , Microbiologia da Água , Adenoviridae/genética , Adenoviridae/isolamento & purificação , Brasil , Monitoramento Ambiental , Fezes/virologia , Humanos , Mamastrovirus/genética , Mamastrovirus/isolamento & purificação , Dados de Sequência Molecular , Norovirus/genética , Norovirus/isolamento & purificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Análise de Sequência de DNA
12.
Virus Res ; 129(2): 166-74, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17714822

RESUMO

Human astroviruses (HAstV) are worldwide recognized as important viral enteropathogens during childhood. This study aims to determine the incidence, genetic diversity and intertype variability of HAstV-1 in children less than 5 years of age enrolled in several studies conducted in Belém/Pará, and São Luís/Maranhão, Brazil, from December 1982 to May 2000. Using EIA and RT-PCR, an overall positivity of 6.1% (155/2.534) was achieved, of these, 140 were positive by RT-PCR. The analysis of a 348bp ORF2 fragment revealed that HAstV-1 was the predominant genotype (85/140, 60.7%) throughout the 18 years of study. Phylogenetic analysis was performed for 81 of these strains, and 76 (93.8%) were genetically classified as HAstV-1a. The remainder of strains (n=5) were assigned to possible new lineages, 1e and 1f. Four of these five strains were detected in 1983 and 1984, and the lineage 1a circulated during 10 consecutive years (1990/2000). Genome sequence variation was found among the HAstV-1 strains involving all lineages, but only five nucleotide changes translated into aminoacid changes over this period, suggesting that HAstV-1 was very stable. The data obtained in this study should be useful for further studies at molecular level, including improvement of disease surveillance based on molecular diagnostic tools, and vaccine development.


Assuntos
Infecções por Astroviridae/epidemiologia , Infecções por Astroviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Mamastrovirus/genética , Epidemiologia Molecular , Sequência de Bases , Brasil/epidemiologia , Pré-Escolar , Diarreia Infantil/epidemiologia , Diarreia Infantil/virologia , Variação Genética , Genótipo , Humanos , Lactente , Recém-Nascido , Mamastrovirus/classificação , Mamastrovirus/isolamento & purificação , Dados de Sequência Molecular , Filogenia
13.
Virus Res ; 126(1-2): 149-58, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17376554

RESUMO

Several reports have identified P[6] specificities in humans and in animals in different countries of the world, but few sequence data are available in public databases. In this work we have characterized the VP4 strains bearing P[6] specificity and NSP4 genotypes among diarrheic young children and diarrheic and non-diarrheic neonates from three studies previously conducted in Belém, Northern region of Brazil. As the to VP8* fragment, we observed a close relationship to both human prototypes of lineage P[6]-Ia (bootstrap of 99%) and porcine sublineages Ib and Ic (89.2-98.1% aa similarity and mean of 95%). With regards to the NSP4, the samples clustered into genotypes A and B. Of note, of the 27 P[6] strains analyzed in the present study and classified as genotype B, 8 (29.6%) were more similar to porcine prototypes when VP8* and NSP4 genes are compared, and were recovered, one from a neonate and seven from diarrheic children. These preliminary findings reinforce that further investigations are needed to assess the relative frequencies of P[6] strains in our region, as well as to investigate the potential for interspecies transmission involving humans and animals, particularly pigs.


Assuntos
Proteínas do Capsídeo/genética , Genes Virais , Glicoproteínas/genética , Infecções por Rotavirus/virologia , Rotavirus/genética , Toxinas Biológicas/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Animais , Antígenos Virais/genética , Brasil , Pré-Escolar , Genótipo , Humanos , Lactente , Recém-Nascido , Dados de Sequência Molecular , Filogenia , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/classificação , Rotavirus/isolamento & purificação , Infecções por Rotavirus/transmissão , Homologia de Sequência de Aminoácidos , Suínos
14.
J Med Microbiol ; 56(Pt 6): 854-859, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17510274

RESUMO

Group A rotaviruses are the main cause of acute gastroenteritis in children throughout the world. The two outer capsid proteins, VP4 and VP7, define the P and G genotypes, respectively. Rotaviruses with P[8]G1, P[4]G2, P[8]G3 and P[8]G4 genotypes are predominant in infecting humans and the G9 genotype is emerging in most continents as the fifth most common G type worldwide. The inner capsid protein VP6 is responsible for subgroup (SG) specificities, allowing classification of rotaviruses into SG I, SG II, SG I+II and SG non-I-non-II. The non-structural protein 4 (NSP4) encoded by segment 10 has a role in viral morphogenesis and five genetic groups have been described, NSP4 genotypes A-E. The aim of this investigation was to characterize the NSP4 and VP6 genes of rotavirus strains recovered from hospitalized children. Thirty rotavirus strains were submitted to RT-PCR followed by sequencing and phylogenetic analysis. Among the different G and P genotype combinations, two distinct genetic groups could be recognized for the NSP4 gene. Twenty-eight clustered with NSP4 genotype B. The two P[4]G2 strains fell into NSP4 genotype A and clustered distinctly, with a 100 % bootstrap value. The strains distinguished within a group were closely related to each other at the nucleotide and amino acid levels. A phylogenetic tree was constructed for the VP6 gene including the human strains RMC100, E210, Wa, US1205 and 1076, and the animal strains Gott, NCDV, SA-11, FI-14 and EW. This is the first report on Brazilian rotavirus strains describing NSP4 genotype A strains associated with VP6 SG I, and NSP4 genotype B strains associated with VP6 SG II.


Assuntos
Antígenos Virais/genética , Proteínas do Capsídeo/genética , Glicoproteínas/genética , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/genética , Toxinas Biológicas/genética , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Brasil , Criança , Criança Hospitalizada , Análise por Conglomerados , Genótipo , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/isolamento & purificação , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
15.
J Med Microbiol ; 56(Pt 3): 313-319, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17314359

RESUMO

Acute gastroenteritis is a major source of morbidity and mortality among young children in developed and developing countries. Human adenoviruses (HAdVs), and in particular species F, are related to childhood diarrhoea worldwide. This study presents the results obtained during an investigation of HAdVs causing acute gastroenteritis in children hospitalized in Rio de Janeiro, RJ, Brazil, from April 1996 to September 2003, as well as in children with diarrhoea living in the slums of Salvador, BA, Brazil, from October 2001 to September 2003. A total of 3060 stool samples was analysed by an enzyme immunoassay for rotavirus and adenovirus (EIARA) and 61 (2%) were found to be positive. HAdV presented with low prevalence throughout the year, with a slight but not significant increase in incidence in late summer and early autumn. Children up to 2 years of age were the most frequently affected (79% of all positive samples). All positive samples were analysed further by generic and species-specific HAdV PCR protocols, confirming 100% specificity of this rapid and inexpensive EIARA. Species F was the most prevalent (65%), despite the occurrence of species A (12%), C, D and co-infection F/D (5% each) and species B and co-infections F/A, F/C and B/D (2% each). In order to type the species F strains as HAdV-40 or -41, generic PCR and a HinfI restriction digest were performed. HAdV-40 and -41 were found to represent 62% (23/37) and 38% (14/37), respectively. These results demonstrated that a combination of generic and species-specific PCRs is useful and reliable for HAdV species and type identification directly from faecal specimens. The results confirmed the endemism of human adenoviruses, mainly species F, in children as aetiological agents of diarrhoea, although the limited sensitivity of EIARA as a screening method may have underestimated their prevalence.


Assuntos
Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/classificação , Adenovírus Humanos/isolamento & purificação , Infecções Comunitárias Adquiridas/virologia , Gastroenterite/virologia , Infecções por Adenovirus Humanos/epidemiologia , Adenovírus Humanos/genética , Antígenos Virais/análise , Brasil/epidemiologia , Pré-Escolar , Infecções Comunitárias Adquiridas/epidemiologia , DNA Viral/genética , Fezes/virologia , Gastroenterite/epidemiologia , Hospitalização , Humanos , Lactente , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Análise de Sequência de DNA
16.
J Med Microbiol ; 56(Pt 4): 524-532, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17374895

RESUMO

A human rotavirus strain (NB-150) was detected in stool samples from a neonate hospitalized for mild/moderate community-acquired diarrhoea. This baby lived in the outskirts of Belém, Brazil, under poor sanitation conditions. The NB-150 strain displayed a typical long electrophoretic pattern with 11 gene segments. It had two VP7 alleles, G1 and G4, and belonged to VP6 subgroup II. A close relatedness with human rotaviruses was shown for VP7 alleles: G1 (96.9-100 % similarity at the amino acid level) and G4 (97.1-100 % similarity at the amino acid level). As for VP6, 95.1-97.5 % similarity at the amino acid level was noted. VP8* and NSP4 genes showed a close relatedness with those of porcine rotavirus strains, as follows: VP8* (95.0 % similarity at the amino acid level) and NSP4 (93.7-96.0 % similarity at the amino acid level). This is believed to be the first report in Brazil of a rotavirus infection involving a strain with G1 and G4 alleles, with VP8* and NSP4 genes of porcine origin. These findings strongly suggest the occurrence of interspecies transmission.


Assuntos
Proteínas do Capsídeo/genética , Glicoproteínas/genética , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/genética , Toxinas Biológicas/genética , Proteínas não Estruturais Virais/genética , Animais , Brasil/epidemiologia , Genótipo , Humanos , Recém-Nascido , Dados de Sequência Molecular , Filogenia , Suínos/virologia
17.
Infect Genet Evol ; 51: 28-32, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28300648

RESUMO

A newly GII.17 Kawazaki_2014 variant strain was detected recently in Brazil. Phylogenetic analysis reveals at least four independent introduction events of this lineage into this country that took place throughout 2014, coinciding with FIFA World Cup in Brazil, 2014, and Hong Kong has been identified as the most likely source of introduction. This variant emerged in Asia causing outbreaks and replacing prevalent GII.4. Emergence of GII.P17/GII.17 variant emphasizes the need for active laboratory surveillance for NoV including molecular epidemiology and studies on virus evolution.


Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Norovirus/genética , Filogenia , RNA Viral/genética , Brasil/epidemiologia , Infecções por Caliciviridae/transmissão , Infecções por Caliciviridae/virologia , Monitoramento Epidemiológico , Fezes/virologia , Gastroenterite/virologia , Genótipo , Hong Kong/epidemiologia , Humanos , Epidemiologia Molecular , Norovirus/classificação , Norovirus/isolamento & purificação , Prevalência
18.
J Virol Methods ; 228: 123-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26611226

RESUMO

Rotavirus A (RVA) and noroviruses (NoV) are the major viral agents of acute gastroenteritis (AGE) worldwide. In the present study, we aimed to evaluate the performance of a one-step duplex quantitative RT-PCR (dRT-qPCR) assay, established for detection and quantification of RVA and NoV genogroup II (GII) using a single DNA standard curve (SC), as well as to investigate the association between fecal viral load and optical density (OD) values, and viruses' genotyping. The results obtained by dRT-qPCR in 530 fecal samples from AGE cases were compared with methods employed for the diagnosis of those viruses as follows: enzyme immunoassay (EIA) and polyacrylamide gel electrophoresis (PAGE) for RVA; and qualitative PCR for NoV. By using dRT-qPCR, we detected RVA and NoV in 353 (66%), increasing the positivity rate by 22.5% for RVA and 11.5% NoV, comparing the number of positive samples. RVA and NoV GII were detected in a range of 5.17 × 10(3) to 6.56 × 10(9) and 3.76 × 10(3) to 9.13 × 10(10) genome copies per gram of feces, respectively. We observed a significant direct correlation between genome copies values and optical density, using dRT-qPCR and EIA assays, respectively (Spearman ρ=0.41; p<0.0001). Viruses characterization demonstrated a predominance of NoV GII.4 Sidney 2012 variant during October 2013 to February 2014, followed by the emergence of RVA genotype G12P[8] in 2014. The established assay using a single SC provides an early feedback concerning detection and quantification, with the advantage of detecting simultaneously RVA and NoV GII, reducing time and reagent costs.


Assuntos
Infecções por Caliciviridae/virologia , Norovirus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções por Rotavirus/virologia , Rotavirus/isolamento & purificação , Infecções por Caliciviridae/diagnóstico , Fezes/virologia , Gastroenterite/virologia , Variação Genética , Genótipo , Humanos , Norovirus/genética , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/economia , Rotavirus/genética , Infecções por Rotavirus/diagnóstico , Análise de Sequência de DNA , Carga Viral
19.
Am J Infect Control ; 44(11): 1411-1413, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27217348

RESUMO

Rotavirus A and human adenovirus dissemination were demonstrated both in a pediatric ward and in a neonatal intensive care unit (NICU) of the same pediatric hospital. Virus detection from fomites samples were higher in the pediatric ward (42.3% [137 out of 324]) than in the NICU (4.5% [7 out of 156]), revealing that cleaning processes used in our NICU are effective in reducing viral contamination, suggesting human adenovirus as a potential biomarker of contamination of hospital fomites.


Assuntos
Adenovírus Humanos/isolamento & purificação , Fômites/virologia , Hospitais Pediátricos , Unidades de Terapia Intensiva Neonatal , Rotavirus/isolamento & purificação , Humanos
20.
Vet J ; 206(1): 115-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26189893

RESUMO

Feline caliciviruses (FCVs) have occasionally been described in cats in association with enteric disease, but an etiological role for these viruses in acute gastroenteritis is still unclear. In this study, molecular characterization of FCV and feline norovirus (FNoV) was undertaken using real-time PCR (RT-PCR) and sequence analysis of the ORF1 region in fecal specimens from 29 diarrheic cats. The specimens were also screened for parvovirus, coronavirus, astrovirus and group A rotavirus. A quantitative one step RT-PCR was also performed to detect and quantitate NoV genogroup IV and the role of these animal caliciviruses in feline gastroenteritis was investigated. This is the first description of enteric FCV and FNoV in South America.


Assuntos
Infecções por Caliciviridae/veterinária , Doenças do Gato/virologia , Surtos de Doenças/veterinária , Gastroenterite/veterinária , Norovirus/isolamento & purificação , Vesivirus/isolamento & purificação , Animais , Brasil , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Doenças do Gato/epidemiologia , Gatos , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/genética , Filogenia , Vesivirus/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA