Search results for " norovirus"

The effect of essential oils on norovirus surrogates

2013

Abstract Essential oils (EOs) have long been applied as flavoring agents in foods, and due to their content in antimicrobial compounds, they have potential as natural agents for food preservation. In this study the effect of three EOs, clove, oregano and zataria, was evaluated on the infectivity of norovirus surrogates, i.e. feline calicivirus (FCV) and murine norovirus (MNV). Different concentrations of EOs were individually mixed with each virus at titers of ca. 7–8 log TCID 50 /ml and incubated for 2 h at 4 °C and 37 °C. The infectivity of the recovered viruses after triplicate treatments was evaluated by cell-culture assays. 2% of oregano EO at 37 °C decreased the FCV titers by 3.75 log…

Viral gastroenteritis in children hospitalised in Sicily, Italy

2006

The aim of the present study was to describe the epidemiologic and clinical characteristics of acute viral gastroenteritis in hospitalised Italian children. A total of 215 stool specimens were collected from January to December 2003 from patients hospitalised in Palermo for acute diarrhoea. Samples were tested for group A rotavirus, astrovirus, adenovirus, norovirus, enteropathogenic bacteria, and parasites. Rotaviruses, mostly belonging to types G1-G4, were detected in 25.1% of samples, astrovirus in 7%, adenovirus in 6%, norovirus in 18.6%, and bacterial agents in 17.2%. No parasitic infections were diagnosed. Mixed infections represented 9.8% of all cases. The mean and median ages of chi…

The role of histo-blood group antigens and microbiota in human norovirus replication in zebrafish larvae

2022

Human norovirus (HuNoV) is the major agent for viral gastroenteritis, causing >700 million infections yearly. Fucose-containing carbohydrates named histo-blood group antigens (HBGAs) are known (co)receptors for HuNoV. Moreover, bacteria of the gut microbiota expressing HBGA-like structures have shown an enhancing effect on HuNoV replication in an in vitro model. Here, we studied the role of HBGAs and the host microbiota during HuNoV infection in zebrafish larvae. Using whole-mount immunohistochemistry, we visualized the fucose expression in the zebrafish gut for the HBGA Lewis X [LeX, α(1,3)-fucose] and core fucose [α(1,6)-fucose]. Costaining of HuNoV-infected larvae proved colocalization o…

Human Intestinal Enteroids to Evaluate Human Norovirus GII.4 Inactivation by Aged-Green Tea

2020

Human noroviruses are the leading cause of epidemic and sporadic acute gastroenteritis worldwide and the most common cause of foodborne illness in the United States. Several natural compounds, such as aged-green tea extract (aged-GTE), have been suggested as ingestible antiviral agents against human norovirus based on data using murine norovirus and feline calicivirus as surrogates. However, in vitro data showing their effectiveness against infectious human norovirus are lacking. We tested the activity of aged-GTE to inhibit human norovirus in a human intestinal enteroids (HIEs) model and Tulane virus in LLC-monkey kidney (LLC-MK2) cell culture. HIE monolayers pretreated with aged-GTE at di…

VALUTAZIONE DELLA PREVALENZA DI NOROVIRUS E VIRUS DELL’EPATITE A (HAV) NEI MOLLUSCHI EDULI LAMELLIBRANCHI IN SICILIA, STRATEGIE DI CONTROLLO E COMUNI…

Capacidad protectora de la leche materna frente a las infecciones por norovirus

2012

En la actualidad se asume que la leche materna es el alimento de elección para el lactante hasta los seis meses de vida, recomendándose que se ofrezca más allá de este periodo junto con la alimentación complementaria. Las ventajas nutricionales de la lactancia materna han sido ampliamente estudiadas, si bien son menos conocidas sus propiedades defensivas. La capacidad protectora frente a la adquisición de infecciones es una propiedad que ofrece un gran beneficio al niño amamantado, especialmente frente a las infecciones producidas por norovirus (causa frecuente de infección intestinal en la infancia). Entre los efectores de esta función defensiva parecen estar implicados agentes de inmunida…

Experimental and CFD evaluation of ozone efficacy against coronavirus and enteric virus contamination on public transport surfaces

2021

The limited information about the routes of the transmission of SARS-CoV-2 within the ongoing pandemic scenario mobilized the administration, industry and academy to develop sanitation and disinfection systems for public and private spaces. Ozone has been proposed as an effective disinfection method against enveloped and non-enveloped viruses, including viruses with similar morphology to SARS-CoV-2. Due to this efficacy, numerous gaseous and aqueous phase ozone applications have emerged potentially to inhibit virus persistence in aerosols, surfaces, and water. In this work, a numerical model, a RANS CFD model for ozone dispersion inside tram and underground coach has been developed includin…

A single method for recovery and concentration of enteric viruses and bacteria from fresh-cut vegetables

2011

Fresh-cut vegetables are prone to be contaminated with foodborne pathogens during growth, harvest, transport and further processing and handling. As most of these products are generally eaten raw or mildly treated, there is an increase in the number of outbreaks caused by viruses and bacteria associated with fresh vegetables. Foodborne pathogens are usually present at very low levels and have to be concentrated (i.e. viruses) or enriched (i.e. bacteria) to enhance their detection. With this aim, a rapid concentration method has been developed for the simultaneous recovery of hepatitis A virus (HAV), norovirus (NV), murine norovirus (MNV) as a surrogate for NV, Escherichia coli O157:H7, List…

Seroprevalence of Norovirus Genogroup IV Antibodies among Humans, Italy, 2010–2011

2014

Antibodies specific to genogroup IV identified in human specimens suggest zoonotic exposure.

Analysis of early strains of the norovirus pandemic variant GII.4 Sydney 2012 identifies mutations in adaptive sites of the capsid protein.

2014

AbstractGlobal surveillance for norovirus identified in 2012 the emergence of a novel pandemic GII.4 variant, termed Sydney 2012. In Italy, the novel pandemic variant was identified as early as November 2011 but became predominant only in the winter season 2012–2013. Upon sequencing and comparison with strains of global origin, the early Sydney 2012 strains were found to differ from those spreading in 2012–2013 in the capsid (ORF2) putative epitopes B, C and D, segregating into a distinct phylogenetic clade. At least three residues (333, 340 and 393, in epitopes B, C and D, respectively) of the VP1 varied among Sydney 2012 strains of different clades. These findings suggest that the spread …