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1.
Viruses ; 14(2)2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35215766

RESUMO

Few studies have shown the presence of norovirus (NoV) RNA in blood circulation but there is no data on norovirus antigenemia. We examined both antigenemia and RNAemia from the sera of children with NoV infections and studied whether norovirus antigenemia is correlated with the levels of norovirus-specific antibodies and clinical severity of gastroenteritis. Both stool and serum samples were collected from 63 children admitted to Mie National Hospital with acute NoV gastroenteritis. Norovirus antigen and RNA were detected in sera by ELISA and real-time RT-PCR, respectively. NoV antigenemia was found in 54.8% (34/62) and RNAemia in 14.3% (9/63) of sera samples. Antigenemia was more common in the younger age group (0-2 years) than in the older age groups, and most patients were male. There was no correlation between stool viral load and norovirus antigen (NoV-Ag) levels (rs = -0.063; Cl -0.3150 to 0.1967; p = 0.6251). Higher levels of acute norovirus-specific IgG serum antibodies resulted in a lower antigenemia OD value (n = 61; r = -0.4258; CI -0.62 to -0.19; p = 0.0006). Norovirus antigenemia occurred more commonly in children under 2 years of age with NoV-associated acute gastroenteritis. The occurrence of antigenemia was not correlated with stool viral load or disease severity.


Assuntos
Antígenos Virais/sangue , Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Norovirus/imunologia , Adolescente , Infecções por Caliciviridae/virologia , Pré-Escolar , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Fezes/virologia , Feminino , Gastroenterite/virologia , Humanos , Lactente , Cinética , Masculino , Epidemiologia Molecular , Norovirus/genética , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral
2.
Sci Rep ; 12(1): 2842, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181717

RESUMO

In neonates, rotavirus (RV) infection is generally nosocomial. The control of rotaviral infection within hospital settings is challenging due to prolonged shedding of the virus and contamination of the surrounding environment. There are few studies that have reported asymptomatic infection within neonates. In this study, neonates were screened for RV infection and possible clinical manifestations that may play a role in RV acquisition were analysed. Stool samples were collected from 523 hospitalized neonates admitted for > 48 h in a low-cost and higher-cost tertiary centre. RV antigen was screened using ELISA and the samples which tested positive were confirmed by semi-nested RT-PCR. RV was detected in 34% of participants and genotypes identified included G12P[11] (44.4%), G10 P[11] (42.6%), G10G12P[11] (10.1%) and G3P[8] (2.9%). ICU admissions were associated with higher viral shedding (p < 0.05). Hospitalization in the low-cost facility ICU was associated with higher RV acquisition risk (p < 0.05). RV was detected in higher rates (36.9%) among neonates with gastrointestinal manifestations. G10P[11] was the predominant genotype for several years (1988-2016) among neonates within India. The preponderance of an emerging G12P[11] genotype and heterotypic distribution was documented. RV surveillance is important to identify emerging strains and establish the road ahead in managing RV infection.


Assuntos
Gastroenterite/diagnóstico , Infecções por Rotavirus/diagnóstico , Rotavirus/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Fezes/virologia , Feminino , Gastroenterite/genética , Gastroenterite/virologia , Genótipo , Hospitalização , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase , Rotavirus/genética , Rotavirus/patogenicidade , Infecções por Rotavirus/genética , Infecções por Rotavirus/virologia
3.
J Gen Virol ; 103(1)2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35077345

RESUMO

Norovirus is the leading cause of epidemic and endemic acute gastroenteritis worldwide and the most frequent cause of foodborne illness in the United States. There is no specific treatment for norovirus infections and therapeutic interventions are based on alleviating symptoms and limiting viral transmission. The immune response to norovirus is not completely understood and mechanistic studies have been hindered by lack of a robust cell culture system. In recent years, the human intestinal enteroid/human intestinal organoid system (HIE/HIO) has enabled successful human norovirus replication. Cells derived from HIE have also successfully been subjected to genetic manipulation using viral vectors as well as CRISPR/Cas9 technology, thereby allowing studies to identify antiviral signaling pathways important in controlling norovirus infection. RNA sequencing using HIE cells has been used to investigate the transcriptional landscape during norovirus infection and to identify antiviral genes important in infection. Other cell culture platforms such as the microfluidics-based gut-on-chip technology in combination with the HIE/HIO system also have the potential to address fundamental questions on innate immunity to human norovirus. In this review, we highlight the recent advances in understanding the innate immune response to human norovirus infections in the HIE system, including the application of advanced molecular technologies that have become available in recent years such as the CRISPR/Cas9 and RNA sequencing, as well as the potential application of single cell transcriptomics, viral proteomics, and gut-on-a-chip technology to further elucidate innate immunity to norovirus.


Assuntos
Infecções por Caliciviridae/imunologia , Gastroenterite/imunologia , Intestinos/virologia , Organoides/imunologia , Gastroenterite/virologia , Humanos , Imunidade Inata , Intestinos/imunologia , Modelos Biológicos , Norovirus/patogenicidade , Norovirus/fisiologia , Organoides/virologia , Análise de Sequência de RNA , Replicação Viral
4.
Cell Rep ; 38(1): 110172, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34986351

RESUMO

During the 2013-2016 West African (WA) Ebola virus (EBOV) outbreak, severe gastrointestinal symptoms were common in patients and associated with poor outcome. Delta peptide is a conserved product of post-translational processing of the abundant EBOV soluble glycoprotein (sGP). The murine ligated ileal loop model was used to demonstrate that delta peptide is a potent enterotoxin. Dramatic intestinal fluid accumulation follows injection of biologically relevant amounts of delta peptide into ileal loops, along with gross alteration of villous architecture and loss of goblet cells. Transcriptomic analyses show that delta peptide triggers damage response and cell survival pathways and downregulates expression of transporters and exchangers. Induction of diarrhea by delta peptide occurs via cellular damage and regulation of genes that encode proteins involved in fluid secretion. While distinct differences exist between the ileal loop murine model and EBOV infection in humans, these results suggest that delta peptide may contribute to EBOV-induced gastrointestinal pathology.


Assuntos
Ebolavirus/metabolismo , Enterotoxinas/toxicidade , Gastroenterite/virologia , Doença pelo Vírus Ebola/patologia , Proteínas do Envelope Viral/toxicidade , Animais , Diarreia/virologia , Feminino , Gastroenterite/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C
5.
BMC Urol ; 22(1): 5, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033051

RESUMO

BACKGROUND: Adenovirus gastroenteritis is a common cause of diarrhea and vomiting in infants, resulting in prerenal acute kidney injury (AKI). However, postrenal AKI due to urinary stones associated with adenovirus gastroenteritis is extremely rare. Here, we describe postrenal AKI due to obstructive ammonium acid urate stones associated with adenovirus gastroenteritis. CASE PRESENTATION: A previously healthy 6-month-old boy had an 11-day history of severe diarrhea and a 5-day history of vomiting. His stool was positive for adenovirus antigens. We initiated fluid replacement therapy. On the second hospital day, he suddenly developed anuria. Abdominal computed tomography revealed bilateral hydronephrosis, left ureteral stones, and right bladder ureteral junction stones. Laboratory data showed that the creatinine level increased to 1.00 mg/dL. We diagnosed postrenal AKI due to obstructive bilateral urinary stones. Urination with stable urine volume resumed spontaneously after hydration. A few stones were found in the urine, which consisted of ammonium acid urate (> 98%). The serum creatinine level improved to 0.25 mg/dL. He was discharged nine days after admission. CONCLUSIONS: We suggest that adenovirus gastroenteritis be considered in pediatric patients with postrenal AKI due to urinary stones.


Assuntos
Injúria Renal Aguda/etiologia , Infecções por Adenoviridae/complicações , Gastroenterite/complicações , Ácido Úrico , Cálculos Urinários/complicações , Gastroenterite/virologia , Humanos , Lactente , Masculino , Ácido Úrico/análise , Cálculos Urinários/química
6.
J Extracell Vesicles ; 11(1): e12172, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34981901

RESUMO

Intestinal commensal bacteria contribute to maintaining gut homeostasis. Disruptions to the commensal flora are linked to the development and persistence of disease. The importance of these organisms is further demonstrated by the widespread ability of enteric viruses to exploit commensal bacteria to enhance viral infection. These viruses interact directly with commensal bacteria, and while the impact of this interaction on viral infection is well described for several viruses, the impact on the commensal bacteria has yet to be explored. In this article, we demonstrate, for the first time, that enteric viruses alter the gene expression and phenotype of individual commensal bacteria. Human and murine norovirus interaction with bacteria resulted in genome-wide differential gene expression and marked changes in the surface architecture of the bacterial cells. Furthermore, the interaction of the virus with bacteria led to increased production of smaller outer membrane vesicles (OMVs). Enhanced production of smaller vesicles was also observed when noroviruses were incubated with other commensal bacteria, indicating a potentially broad impact of norovirus interaction. The vesicle production observed in the in vivo model followed a similar trend where an increased quantity of smaller bacterial vesicles was observed in stool collected from virus-infected mice compared to mock-infected mice. Furthermore, changes in vesicle size were linked to changes in protein content and abundance, indicating that viral binding induced a shift in the mechanism of the OMV biogenesis. Collectively, these data demonstrate that enteric viruses induce specific changes in bacterial gene expression, leading to changes in bacterial extracellular vesicle production that can potentially impact host responses to infection.


Assuntos
Membrana Externa Bacteriana/metabolismo , Vesículas Extracelulares/metabolismo , Gastroenterite/microbiologia , Microbioma Gastrointestinal , Norovirus/fisiologia , Animais , Membrana Externa Bacteriana/ultraestrutura , Enterobacter cloacae/genética , Enterobacter cloacae/metabolismo , Gastroenterite/metabolismo , Gastroenterite/virologia , Humanos , Camundongos , Interações Microbianas
7.
Pediatrics ; 149(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34918158

RESUMO

OBJECTIVES: To inform next steps in pediatric diarrhea burden reduction by understanding the shifting enteropathogen landscape after rotavirus vaccine implementation. METHODS: We conducted a case-control study of 1788 medically attended children younger than 5 years, with and without gastroenteritis, after universal rotavirus vaccine implementation in Peru. We tested case and control stools for 5 viruses, 19 bacteria, and parasites; calculated coinfection-adjusted attributable fractions (AFs) to determine pathogen-specific burdens; and evaluated pathogen-specific gastroenteritis severity using Clark and Vesikari scales. RESULTS: Six pathogens were independently positively associated with gastroenteritis: norovirus genogroup II (GII) (AF 29.1, 95% confidence interval [CI]: 28.0-32.3), rotavirus (AF 8.9, 95% CI: 6.8-9.7), sapovirus (AF 6.3, 95% CI: 4.3-7.4), astrovirus (AF 2.8, 95% CI: 0.0-4.0); enterotoxigenic Escherichia coli heat stable and/or heat labile and heat stable (AF 2.4, 95% CI: 0.6-3.1), and Shigella spp. (AF 2.0, 95% CI: 0.4-2.2). Among typeable rotavirus cases, we most frequently identified partially heterotypic strain G12P[8] (54 of 81, 67%). Mean severity was significantly higher for norovirus GII-positive cases relative to norovirus GII-negative cases (Vesikari [12.7 vs 11.8; P < .001] and Clark [11.7 vs 11.4; P = .016]), and cases in the 6- to 12-month age range relative to cases in other age groups (Vesikari [12.7 vs 12.0; P = .0002] and Clark [12.0 vs 11.4; P = .0016]). CONCLUSIONS: Norovirus is well recognized as the leading cause of pediatric gastroenteritis in settings with universal rotavirus vaccination. However, sapovirus is often overlooked. Both norovirus and sapovirus contribute significantly to the severe pediatric disease burden in this setting. Decision-makers should consider multivalent vaccine acquisition strategies to target multiple caliciviruses in similar countries after successful rotavirus vaccine implementation.


Assuntos
Gastroenterite/microbiologia , Gastroenterite/prevenção & controle , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus , Estudos de Casos e Controles , Pré-Escolar , Diarreia/microbiologia , Diarreia/prevenção & controle , Diarreia/virologia , Fezes/microbiologia , Fezes/virologia , Gastroenterite/parasitologia , Gastroenterite/virologia , Genótipo , Humanos , Norovirus/genética , Peru , Estudos Prospectivos , Rotavirus/genética , Sapovirus/genética , Índice de Gravidade de Doença
8.
J Med Virol ; 94(2): 610-615, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34427937

RESUMO

Rotaviruses belonging to species A (RVA) remain among the most common causes of severe gastroenteritis in children aged <5 years, leading to substantial morbidity and mortality worldwide. Genome reassortment events between two human strains or human and animal strains represent one of the mechanisms which appear to generate the broad genetic variability of circulating. According to a nucleotide, sequence-based classification system, RVA strains are currently classified into three genotype constellations including Wa-like (genogroup I), DS-1-like (genogroup II), and AU-like (genogroup III). The present study reports the detection of an unusual RVA G4P[6] strain (coded as strain HSE005), which might have originated from a natural reassortment event between human and animal RVA strains. Molecular characterization of this isolate showed that it belonged to genogroup II, genotype G4P[6]. In addition, two genes (VP3 and NSP4) of this strain denoted evidence of reassortment events involving strains of distinct zoonotic evolutionary origins. Therefore, we propose that a new G4P[6] strain was identified, highlighting a possible first zoonotic transmission including a reassortment event that involved the VP3 gene.


Assuntos
Gastroenterite/virologia , Genótipo , Rotavirus/genética , Brasil , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , RNA Viral , Rotavirus/classificação , Rotavirus/isolamento & purificação
9.
J Med Virol ; 94(2): 616-624, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34528724

RESUMO

Norovirus (NoV) is the leading cause of acute gastroenteritis (AGE) worldwide. Globally, the GII.4 Sydney 2012 strain has predominated since 2012, although GII.4 variant strains have caused AGE outbreaks in China. Recent patterns of NoV genotype distributions in 6011 children with AGE in Tianjin, China were investigated. NoV was detected using real-time reverse-transcriptase polymerase chain reaction and sequencing of partial sequences of the viral capsid gene. NoV genotypes were determined, and phylogenetic analysis was conducted. Epidemiological and clinical data were compared between children infected with different NoV genotypes. NoV was detected in 27.6% of the specimens tested. GII.4 strains comprised 49.4% infections, followed by GII.3 at 39.9%. Genotypes GII.2, GII.13, GII.17, GII.1, GII.6, and GII.14 were also detected. NoV was detected during most of the year, with a peak season of cases in the winter. Diarrhea, vomiting, fever, abdominal pain, and dehydration were present in patients with NoV infection. The main genotypes were GII.4 and GII.3, with a slight increase in GII.2, beginning in March 2017. Among the GII.4 strains, GII.4 Sydney 2012 was the only epidemic strain in Tianjin. Patients with GII.4 genotypes were more likely to present with diarrhea and vomiting than those with GII.3. Children with GII. Others were prone to suffered from dehydration and abdominal pain than those with GII.3. NoV GII has become the main cause of viral AGE in Tianjin, China. The predominant genotypes of NoV were GII.4 and GII.3. Identification of emerging genotypes is crucial for the prevention and control of NoV-caused AGE.


Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/classificação , Norovirus/genética , Infecções por Caliciviridae/fisiopatologia , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Diarreia/etiologia , Feminino , Febre/etiologia , Genótipo , Humanos , Lactente , Masculino , Epidemiologia Molecular , Norovirus/isolamento & purificação , Filogenia , Estações do Ano , Vômito/etiologia
10.
Sci Rep ; 11(1): 23218, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34853333

RESUMO

Norovirus is the leading cause of outbreaks of acute viral gastroenteritis. We carried out this study to investigate outbreaks in long-term care facilities reported in 2017 and 2018 in Catalonia (Spain). The characteristics of the centers, exposed persons and the genogroups responsible were analyzed. Viral loads were estimated. The attack rate (AR) of the outbreaks studied, and the rate ratio (RR) and the odds ratio (OR) and their 95% confidence intervals as measures of association were calculated. The mean cycle thresholds were compared using the t-test for independent means. We included 30 outbreaks (4631 exposed people). The global AR was 25.93%. The RR of residents vs. staff was 2.28 (95% CI 2.0-2.6). The RR between AR in residents with total or severe dependence vs. residents with moderate, low or no-dependence was 1.23 (95% CI 1.05-1.45). The AR were higher in smaller centers than in larger ones (38.47% vs. 19.25% and RR 2; 95% CI 1.82-2.2). GII was responsible for 70% of outbreaks. No association was found between the genogroup and presenting symptoms (OR 0.96; 95% CI 0.41-2.26). Viral loads were higher in symptomatic than in asymptomatic patients (p = 0.001).


Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Norovirus/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/virologia , Surtos de Doenças , Feminino , Gastroenterite/diagnóstico , Gastroenterite/virologia , Humanos , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Casas de Saúde , Estudos Prospectivos , Espanha/epidemiologia , Adulto Jovem
11.
Sci Rep ; 11(1): 23266, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34853390

RESUMO

Human astrovirus (HAstV) is one of the common causes of acute gastroenteritis in children. The investigation of molecular epidemiology of HAstV is essential for monitoring the emergence and/or re-emergence of new HAstV genotypes, as well as understanding the evolution of HAstV circulating in children suffering from acute gastroenteritis. The present study aimed to investigate the prevalence and distribution of HAstVs strains circulating in children hospitalized with acute gastroenteritis in Chiang Mai, Thailand during 2017-2020. A total of 1500 fecal specimens collected from children with acute gastroenteritis were screened for HAstV by RT-PCR that targeted the partial RdRp in ORF1b and strains were characterized by sequencing and phylogenetic analysis. Of the 1500 fecal samples, 39 (2.6%) were positive for HAstV. Of these, both classic and novel HAstV genotypes, including classic HAstV1-HAstV5, novel HAstV-MLB1, MLB2, and HAstV-VA2, were detected. The data in this study revealed a high divergence of HAstV genotypes circulating in pediatric patients admitted to the hospitals with acute gastroenteritis in Chiang Mai, Thailand during 2017-2020.


Assuntos
Infecções por Astroviridae/virologia , Gastroenterite/virologia , Variação Genética , Mamastrovirus/genética , Doença Aguda , Adolescente , Infecções por Astroviridae/epidemiologia , Criança , Pré-Escolar , Fezes/virologia , Genótipo , Hospitalização , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , Filogenia , Prevalência , RNA Viral/genética , Especificidade da Espécie , Tailândia/epidemiologia
12.
J Infect Dev Ctries ; 15(11): 1701-1707, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34898499

RESUMO

INTRODUCTION: Most hospitals rely on rapid antigen-detection kits for the diagnosis of rotavirus infection. Several small studies reviewed the sensitivity and specificity of some of these kits. These studies showed discrepancy in results obtained for sensitivity and specificity that varied according to the type of kit used, area of study, and type of test used as standard for diagnosis of rotavirus infection. The objective of the study is to determine the sensitivity and specificity of five commonly used rotavirus immunoassay kits in comparison to RT-PCR as standard. METHODOLOGY: Stool samples (N = 1,414) collected from children under 5 years of age hospitalized with gastroenteritis were tested for rotavirus by immunoassay kits and RT-PCR in a prospective hospital-based surveillance study conducted at 7 centers in Lebanon. Concordance and discrepancy between the two methods was used to calculate sensitivity and specificity, using RT-PCR as the "gold standard". RESULTS: The sensitivity and specificity were respectively 95.08% and 86.62% for the SD Bioline® (Standard Diagnostics, Inc, South Korea) kit calculated on 645 samples, 65.86% and 45.90% for the VIROTECT® (Trinity Biotech, Ireland) kit calculated on 327 samples, 83.9% and 64.2% for the Rota-Strip (C-1001) (Coris Bioconcept, Belgium) calculated on 95 samples, 52.3% and 10.9% for the Acon® (Acon Laboratories, Inc, California, USA) kit calculated on 122 samples, 68.1% and 20% for the VIKIA® Rota-Adéno (Biomerieux, France) kit calculated on 32 samples. CONCLUSION: A wide discrepancy was detected between the calculated and advertised sensitivity and specificity for most of the kits.


Assuntos
Gastroenterite/diagnóstico , Imunoensaio/normas , Kit de Reagentes para Diagnóstico/normas , Infecções por Rotavirus/diagnóstico , Pré-Escolar , Fezes/virologia , Gastroenterite/virologia , Humanos , Lactente , Estudos Prospectivos , Kit de Reagentes para Diagnóstico/virologia , Reação em Cadeia da Polimerase em Tempo Real , Rotavirus , Sensibilidade e Especificidade
13.
Viruses ; 13(12)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34960668

RESUMO

Human Norovirus is currently the main viral cause of acute gastroenteritis (AGEs) in most countries worldwide. Nearly 50 years after the discovery of the "Norwalk virus" by Kapikian and colleagues, the scientific and medical community continue to generate new knowledge on the full biological and disease spectrum of Norovirus infection. Nevertheless, several areas remain incompletely understood due to the serious constraints to effectively replicate and propagate the virus. Here, we present a narrated historic perspective and summarize our current knowledge, including insights and reflections on current points of interest for a broad medical community, including clinical and molecular epidemiology, viral-host-microbiota interactions, antivirals, and vaccine prototypes. We also include a reflection on the present and future impacts of the COVID-19 pandemic on Norovirus infection and disease.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/prevenção & controle , Gastroenterite/epidemiologia , Gastroenterite/prevenção & controle , Norovirus/fisiologia , Antivirais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Infecções por Caliciviridae/microbiologia , Infecções por Caliciviridae/virologia , Gastroenterite/microbiologia , Gastroenterite/virologia , Microbioma Gastrointestinal , Interações Hospedeiro-Patógeno , Humanos , Norovirus/genética , Norovirus/imunologia , SARS-CoV-2 , Vacinas Virais/imunologia
14.
Viruses ; 13(12)2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34960760

RESUMO

Rotavirus is the major cause of severe gastroenteritis in children aged <5 years. Introduction of the G1P[8] Rotarix® rotavirus vaccine in Malawi in 2012 has reduced rotavirus-associated hospitalisations and diarrhoeal mortality. However, the impact of rotavirus vaccine on the severity of gastroenteritis presented in children requiring hospitalisation remains unknown. We conducted a hospital-based surveillance study to assess the impact of Rotarix® vaccination on the severity of gastroenteritis presented by Malawian children. Stool samples were collected from children aged <5 years who required hospitalisation with acute gastroenteritis from December 2011 to October 2019. Gastroenteritis severity was determined using Ruuska and Vesikari scores. Rotavirus was detected using enzyme immunoassay. Rotavirus genotypes were determined using nested RT-PCR. Associations between Rotarix® vaccination and gastroenteritis severity were investigated using adjusted linear regression. In total, 3159 children were enrolled. After adjusting for mid-upper arm circumference (MUAC), age, gender and receipt of other vaccines, all-cause gastroenteritis severity scores were 2.21 units lower (p < 0.001) among Rotarix®-vaccinated (n = 2224) compared to Rotarix®-unvaccinated children (n = 935). The reduction in severity score was observed against every rotavirus genotype, although the magnitude was smaller among those infected with G12P[6] compared to the remaining genotypes (p = 0.011). Each one-year increment in age was associated with a decrease of 0.43 severity score (p < 0.001). Our findings provide additional evidence on the impact of Rotarix® in Malawi, lending further support to Malawi's Rotarix® programme.


Assuntos
Gastroenterite/prevenção & controle , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Rotavirus/imunologia , Pré-Escolar , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Gastroenterite/patologia , Gastroenterite/virologia , Genótipo , Hospitalização , Humanos , Lactente , Malaui/epidemiologia , Masculino , Rotavirus/classificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/patologia , Infecções por Rotavirus/virologia , Índice de Gravidade de Doença , Vacinação , Vacinas Atenuadas/administração & dosagem
15.
Viruses ; 13(12)2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34960634

RESUMO

Metagenomics based on the next-generation sequencing (NGS) technique is a target-independent assay that enables the simultaneous detection and genomic characterization of all viruses present in a sample. There is a limited amount of data about the virome of individuals with gastroenteritis (GI). In this study, the enteric virome of 250 individuals (92% were children under 5 years old) with GI living in the northeastern and northern regions of Brazil was characterized. Fecal samples were subjected to NGS, and the metagenomic analysis of virus-like particles (VLPs) identified 11 viral DNA families and 12 viral RNA families. As expected, the highest percentage of viral sequences detected were those commonly associated with GI, including rotavirus, adenovirus, norovirus (94.8%, 82% and 71.2%, respectively). The most common co-occurrences, in a single individual, were the combinations of rotavirus-adenovirus, rotavirus-norovirus, and norovirus-adenovirus (78%, 69%, and 62%, respectively). In the same way, common fecal-emerging human viruses were also detected, such as parechovirus, bocaporvirus, cosavirus, picobirnavirus, cardiovirus, salivirus, and Aichivirus. In addition, viruses that infect plants, nematodes, fungi, protists, animals, and arthropods could be identified. A large number of unclassified viral contigs were also identified. We show that the metagenomics approach is a powerful and promising tool for the detection and characterization of different viruses in clinical GI samples.


Assuntos
Gastroenterite/virologia , Metagenômica , Viroma/genética , Vírus/genética , Doença Aguda , Adenoviridae/genética , Adolescente , Adulto , Idoso , Bacteriófagos/genética , Brasil/epidemiologia , Criança , Pré-Escolar , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Norovirus/genética , Rotavirus/genética , Vírus/classificação , Vírus/isolamento & purificação , Adulto Jovem
16.
Microbiol Spectr ; 9(3): e0217821, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34937184

RESUMO

Human bocavirus (HBoV) has been recognized as one of the common pathogens which cause respiratory disease and acute gastroenteritis in children worldwide. Recently, our studies reported the detection of HBoV in children with acute gastroenteritis and in oysters in Thailand. However, studies on the presence of HBoV in environmental waters in Thailand have not yet been conducted. In this study, 126 environmental water samples collected from November 2016 to July 2018 were investigated. Detection of HBoV was based on amplification of the VP1/VP2 region of the HBoV genome by nested PCR followed by nucleotide sequencing and phylogenetic analysis. HBoV was detected in 34 out of 126 samples (27.0%). All four HBoV genotypes, HBoV1 to HBoV4, were detected. HBoV2 was the most frequently detected genotype (61.8%), followed by HBoV1 (23.5%), HBoV4 (8.8%), and HBoV3 (5.9%). The highest detection rate of HBoV was observed during the warmest months in Thailand: April 2017 and March 2018. Phylogenetic analysis of VP1/VP2 nucleotide sequences of HBoV genotypes revealed that all four of the genotypes detected in environmental waters were closely related to genotypes detected in patients with acute gastroenteritis, which had been reported previously in the same geographical area. This study reports the existence of multiple HBoV genotypes in environmental waters and provides evidence of a considerably high magnitude of HBoV contamination in these waters. These findings demonstrate the potential risk of waterborne transmission of HBoV to humans. IMPORTANCE Recently, we reported the detection of HBoV genotypes 1, 2, and 3 in pediatric patients with acute gastroenteritis, and the detection of HBoV1 and 2 in oysters in Thailand. In this study, we reported the detection of HBoV1, 2, 3, and 4 contamination in environmental waters within the same geographic area. Phylogenetic analysis demonstrated that the HBoV genotypes detected in environmental waters and in oysters were closely related to HBoV detected in patients. These findings imply that HBoV contamination in oysters and in environmental waters could be a potential sources of foodborne and waterborne transmission to humans.


Assuntos
Água Doce/virologia , Gastroenterite/virologia , Bocavirus Humano/genética , Infecções por Parvoviridae/virologia , Gastroenterite/epidemiologia , Genótipo , Bocavirus Humano/classificação , Bocavirus Humano/isolamento & purificação , Humanos , Infecções por Parvoviridae/epidemiologia , Filogenia , Tailândia/epidemiologia
17.
Viruses ; 13(11)2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34834961

RESUMO

Nested PCRs with circovirus/cyclovirus pan-rep (replicase gene) primers detected eukaryotic circular Rep-encoding single-stranded DNA (CRESS DNA) viruses in three (samples CN9E, CN16E and CN34) of 18 canine parvovirus-2-positive fecal samples from household dogs with hemorrhagic gastroenteritis on the Caribbean island of Nevis. The complete genomes of CRESS DNA virus CN9E, CN16E and CN34 were determined by inverse nested PCRs. Based on (i) genome organization, (ii) location of the putative origin of replication, (iii) pairwise genome-wide sequence identities, (iv) the presence of conserved motifs in the putative replication-associated protein (Rep) and the arginine-rich region in the amino terminus of the putative capsid protein (Cp) and (v) a phylogenetic analysis, CN9E, CN16E and CN34 were classified as cycloviruses. Canine-associated cycloviruses CN16E and CN34 were closely related to each other and shared low genome-wide nucleotide (59.642-59.704%), deduced Rep (35.018-35.379%) and Cp (26.601%) amino acid sequence identities with CN9E. All the three canine-associated cycloviruses shared < 80% genome-wide pairwise nucleotide sequence identities with cycloviruses from other animals/environmental samples, constituting two novel species (CN9E and CN16E/34) within the genus Cyclovirus. Considering the feeding habits of dogs, we could not determine whether the cycloviruses were of dietary origin or infected the host. Interestingly, the CN9E putative Rep-encoding open reading frame was found to use the invertebrate mitochondrial genetic code with an alternative initiation codon (ATA) for translation, corroborating the hypothesis that cycloviruses are actually arthropod-infecting viruses. To our knowledge, this is the first report on the detection and complete genome analysis of cycloviruses from domestic dogs.


Assuntos
Circoviridae/classificação , Circoviridae/isolamento & purificação , Doenças do Cão/virologia , Gastroenterite/virologia , Filogenia , Sequência de Aminoácidos , Animais , Proteínas do Capsídeo/genética , Circoviridae/genética , Vírus de DNA/genética , DNA Viral/genética , Cães , Fezes/virologia , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta , Parvovirus Canino/classificação , Parvovirus Canino/genética , Parvovirus Canino/isolamento & purificação , São Cristóvão e Névis , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
18.
Viruses ; 13(11)2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34834968

RESUMO

Noroviruses are responsible for almost a fifth of all cases of gastroenteritis worldwide. The calicivirus capsid is composed of 180 copies of VP1 with a molecular weight of ~58 kDa. This coat protein is divided into the N-terminus (N), the shell (S) and C-terminal protruding (P) domains. The S domain forms a shell around the viral RNA genome, while the P domains dimerize to form protrusions on the capsid surface. The P domain is subdivided into P1 and P2 subdomains, with the latter containing the binding sites for cellular receptors and neutralizing antibodies. Reviewed here are studies on murine norovirus (MNV) showing that the capsid responds to several physiologically relevant cues; bile, pH, Mg2+, and Ca2+. In the initial site of infection, the intestinal tract, high bile and metal concentrations and low pH cause two significant conformational changes: (1) the P domain contracts onto the shell domain and (2) several conformational changes within the P domain lead to enhanced receptor binding while blocking antibody neutralization. In contrast, the pH is neutral, and the concentrations of bile and metals are low in the serum. Under these conditions, the loops at the tip of the P domain are in the open conformation with the P domain floating on a linker or tether above the shell. This conformational state favors antibody binding but reduces interactions with the receptor. In this way, MNV uses metabolites and environmental cues in the intestine to optimize cellular attachment and escape antibody binding but presents a wholly different structure to the immune system in the serum. To our knowledge, this is the first example of a virus shapeshifting in this manner to escape the immune response.


Assuntos
Gastroenterite/imunologia , Gastroenterite/virologia , Norovirus/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Bile , Sítios de Ligação , Capsídeo/metabolismo , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Microscopia Crioeletrônica , Genoma Viral , Camundongos , Modelos Moleculares , Norovirus/genética , Ligação Proteica , Domínios Proteicos
19.
Mar Drugs ; 19(11)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34822462

RESUMO

Norovirus infections belong to the most common causes of human gastroenteritis worldwide and epidemic outbreaks are responsible for hundreds of thousands of deaths annually. In humans, noroviruses are known to bind to gastrointestinal epithelia via recognition of blood-group active mucin-type O-glycans. Considering the involvement of l-α-fucose residues in these glycans, their high valency on epithelial surfaces far surpasses the low affinity, though specific interactions of monovalent milk oligosaccharides. Based on these findings, we attempted to identify polyfucoses (fucans) with the capacity to block binding of the currently most prevalent norovirus strain GII.4 (Sydney, 2012, JX459908) to human and animal gastrointestinal mucins. We provide evidence that inhibitory effects on capsid binding are exerted in a competitive manner by α-fucosyl residues on Fucus vesiculosus fucoidan, but also on the galacto-fucan from Undaria pinnatifida and their oligo-fucose processing products. Insight into novel structural aspects of fucoidan and derived oligosaccharides from low-mass Undaria pinnatifida were revealed by GCMS and MALDI mass spectrometry. In targeting noroviral spread attenuation, this study provides first steps towards a prophylactic food additive that is produced from algal species.


Assuntos
Antivirais/farmacologia , Fucus , Norovirus/efeitos dos fármacos , Polissacarídeos/farmacologia , Undaria , Animais , Antivirais/química , Organismos Aquáticos , Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Trato Gastrointestinal , Humanos , Polissacarídeos/química
20.
PLoS One ; 16(11): e0259145, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34727123

RESUMO

There is a large burden of norovirus disease in child-care centers in Australia and around the world. Despite the ubiquity of norovirus outbreaks in child-care centers, little is known about the extent of this burden within the child-care center and the surrounding household clusters. Therefore, we performed an in-depth analysis of a gastroenteritis outbreak to examine the patterns of transmissions, household attack rates and the basic reproduction number (R0) for Norovirus in a child-care facility. We used data from parental interviews of suspected cases sent home with gastroenteritis at a child-care center between 24th of August and 18th of September 2020. A total of 52 persons in 19 household clusters were symptomatic in this outbreak investigation. Of all transmissions, 23 (46.9%) occurred in the child-care center, the rest occurring in households. We found a household attack rate of 36.5% (95% CI 27.3, 47.1%). Serial intervals were estimated as mean 2.5 ± SD1.45 days. The R0, using time-dependent methods during the growth phase of the outbreak (days 2 to 8) was 2.4 (95% CI 1.50, 3.50). The count of affected persons of a child-care center norovirus outbreak is approximately double the count of the total symptomatic staff and attending children. In the study setting, each symptomatic child-care attendee likely infected one other child-care attendee or staff and just over one household contact on average.


Assuntos
Norovirus , Criança , Pré-Escolar , Gastroenterite/virologia , Humanos , Lactente
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