Search results for "noroviru"

Aproximaciones moleculares al estudio de las interacciones de rotavirus y norovirus con el huésped

2020

Los norovirus humanos son los principales agentes etiológicos de gastroenteritis aguda en todo el mundo. Aunque los norovirus son muy diversos (se han detectado más de 30 genotipos en humanos), durante los últimos 40 años la mayoría de los brotes y epidemias han sido causados por cepas del genotipo GII.4, lo que plantea interrogantes sobre su persistencia en la población. Entre otras posibles explicaciones, se considera que la evasión inmunológica es la principal causa de su éxito. Para estudiar en detalle el reconocimiento y la evasión de anticuerpos, analizamos un epítopo conformacional reconocido por un anticuerpo monoclonal (3C3G3) mediante mutagénesis dirigida y resonancia superficial …

Molecular Virology of Enteric Viruses (with Emphasis on Caliciviruses)

2006

Human caliciviruses are members of the family Caliciviridae and are responsible for a majority of the outbreaks of acute nonbacterial gastroenteritis. In fact, they now are considered a common cause of sporadic cases of diarrhea in the community (Glass et al., 2000b; Koopmans et al., 2002; Lopman et al., 2002; Hutson et al., 2004). These viruses were implicated in as many as 95% of the reported viral gastroenteritis outbreaks examined over a 4.5-year period in the United States (Fankhauser et al., 2002), and similar high incidence rates have been found in other studies (Maguire et al., 1999; Glass et al., 2000b; Koopmans et al., 2000; Lopman et al., 2003). Common features of the Calicivirid…

Norovirus and Foodborne Disease: A Review

2014

Investigation and control of a Norovirus outbreak of probable waterborne transmission through a municipal groundwater system

2014

During March 2011 an outbreak of gastroenteritis occurred in Santo Stefano di Quisquina, Agrigento, Sicily, Italy. Within two weeks 156 cases were identified among the 4,965 people living in the municipality. An epidemiological investigation was conducted to characterize the outbreak and target the control measures. A case was defined as a person developing diarrhea or vomiting during February 27–March 13, 2011. Stool specimens were collected from 12 cases. Norovirus (NoV) genotype GII.4 variant New Orleans 2009 was identified in stool samples from 11 of 12 cases tested (91.7%). Epidemiological investigations suggested a possible association with municipal drinking water consumption. Water …

Norovirus infections and seroprevalence of genotype gii.4-specific antibodies in a spanish population

2015

Genotype II.4 noroviruses (NoVs) are a leading cause of epidemic acute gastroenteritis in children and adults worldwide. The prevalence of different NoV genotypes causing outbreaks and sporadic cases of acute gastroenteritis in the region of Valencia, Spain, during a 4-year period (2008–11) was investigated. NoVs were detected in 42 out of 55 (76.3%) outbreaks and in 26 out of 332 (7.8%) sporadic cases of acute gastroenteritis. Genogroup GII strains were predominant in outbreaks and sporadic cases. Different genotype GII.4 variants were found (Yerseke_2006a, Den Haag_2006b, Apeldoorn_2007, and New Orleans_2009), with the latter variant detected most frequently (35.3%). A recombinant P domai…

Sequential evolution of genotype GII.4 norovirus variants causing gastroenteritis outbreaks from 2001 to 2006 in Eastern Spain.

2008

Noroviruses are the most common cause of outbreaks of viral gastroenteritis worldwide. Norovirus outbreaks were surveyed in Catalonia and the region of Valencia (Eastern Spain) between January 2001 and December 2006 as part of the European Union funded network "Food-borne viruses in Europe". During this time the etiology and epidemiological features of 194 outbreaks of acute non-bacterial gastroenteritis were investigated and norovirus was identified as causing 169 (87.1%) of them. Molecular epidemiology of viral strains was studied by RT-PCR and sequencing part of the RNA polymerase gene in ORF1 from 153 outbreak strains. The most commonly identified norovirus genotype was GII.4 (71.9% of …

Acute gastroenteritis outbreaks in Catalonia, Spain: norovirus versus Salmonella.

2008

Objective. To describe the epidemiology of norovirus (NV) and Salmonella gastroenteritis outbreaks in Catalonia between 15 October 2004 and 30 October 2005. Material and methods. Epidemiological data were obtained from outbreak reports. The aetiologic agent was investigated by culture for enteric bacteria, enzyme immunoanalyses, reverse transcription polymerase chain reaction (RT-PCR) and molecular epidemiology genotyping for NV. The x 2 test was used to compare proportions. Incidence rates and their confidence intervals (CI) were calculated assuming a Poisson distribution. Results. A total of 225 acute gastroenteritis (AG) outbreaks were reported, with 3436 persons affected and 115 hospita…

Epidemiology of foodborne Norovirus outbreaks in Catalonia, Spain

2008

Abstract Background Noroviruses are one of the principal biological agents associated with the consumption of contaminated food. The objective of this study was to analyse the size and epidemiological characteristics of foodborne outbreaks of gastroenteritis in Catalonia, a region in the northeast of Spain. Methods In all reported outbreaks of gastroenteritis associated with food consumption, faecal samples of persons affected were analysed for bacteria and viruses and selectively for parasites. Study variables included the setting, the number of people exposed, age, sex, clinical signs and hospital admissions. The study was carried out from October 2004 to October 2005. Results Of the 181 …

Increase in viral gastroenteritis outbreaks in Europe and epidemic spread of new norovirus variant.

2004

Background Highly publicised outbreaks of norovirus gastroenteritis in hospitals in the UK and Ireland and cruise ships in the USA sparked speculation about whether this reported activity was unusual. Methods We analysed data collected through a collaborative research and surveillance network of viral gastroenteritis in ten European countries (England and Wales were analysed as one region). We compiled data on total number of outbreaks by month, and compared genetic sequences from the isolated viruses. Data were compared with historic data from a systematic retrospective review of surveillance systems and with a central database of viral sequences. Findings Three regions (England and Wales,…

Caratterizzazione molecolare di norovirus GIV ed altri virus enterici in molluschi bivalvi : uno studio preliminare

2011

I virus enterici si replicano nell’intestino umano e possono essere eliminati dagli individui infetti ad elevate concentrazioni; pertanto i reflui urbani possono trasportare una grande quantità di patogeni responsabili di infezioni oro-fecali e contaminare le acque superficiali, incluse quelle marine. I molluschi bivalvi eduli sono spesso implicati nella trasmissione di malattie gastroenteriche di origine virale in quanto, essendo organismi filtratori, rappresentano un potenziale serbatoio di agenti patogeni e sostanze tossiche. Nonostante i miglioramenti delle tecniche per il trattamento delle acque reflue e la classificazione delle aree di allevamento e raccolta dei molluschi, il rischio …