Outbreak Of Norovirus Gastroenteritis Research Articles

Prevention, protocols, and lab capacity: lessons from a norovirus outbreak in the Algarve.

This brief report presents the findings of an epidemiological investigation into a large-scale outbreak of norovirus gastroenteritis that occurred in a hotel in Algarve, Portugal, in August 2022. A total of 244 cases were reported, primarily affecting Portuguese families, with the parents aged 40-50 years and the children aged 0-19 years. Reported symptoms included vomiting, nausea, abdominal pain, and diarrhoea. Norovirus genotype GI.3 [P3] was detected in stool samples from eight probable cases, while food samples tested negative for norovirus and common pathogenic bacteria. The investigation data collected suggest that the source of the outbreak was likely in the hotel's common areas, with subsequent person-to-person transmission in other areas. The final report emphasizes the importance of improving outbreak prevention and control measures, including the development of a foodborne outbreak investigation protocol, the establishment of an outbreak response team, and the enhancement of regional laboratory capacity.

Norovirus Gastroenteritis Outbreak in Kurdistan Province, Iran: Contamination of the Water Supply System

Background: Noroviruses are the most common known causes of non-bacterial acute gastroenteritis worldwide. Norovirus gastroenteritis usually presents with vomiting and diarrhea in the winter. Methods: This cross-sectional study was conducted to evaluate the outbreak of gastroenteritis in one of the villages of Kurdistan Province, Iran, from February 1 to 12, 2019. In this period, 149 people developed joint illness and symptoms of diarrhea, vomiting, and abdominal cramps, whose information was recorded. Data analysis was done with Stata7 software. Results: The attack rate of the total population in the village was 31.17% (26.5% in men and 36.24% in women). The median age of the patients was 26.5 years. The mean patients’ age on the first days of the outbreak was less than on the other days, and this relationship was statistically significant (P=0.003). The most common symptoms were non-bloody diarrhea (57.71%), vomiting (52.34%), abdominal cramps (26.17%), and nausea (24.83%). According to the shape of the epidemic curve, the outbreak was a community-wide outbreak caused by the norovirus. Conclusion: Based on clinical evidence, epidemiological examination, and human and water samples analyses, outbreaks occurred due to the consumption of drinking water contaminated with norovirus. To prevent similar outbreaks, it is recommended to fix the bugs observed in the water supply system and implement the water safety program.

A norovirus gastroenteritis outbreak in an Australian child-care center: A household-level analysis.

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.

Norovirus gastroenteritis outbreaks in military units: a systematic review

IntroductionNorovirus gastroenteritis is one of the most frequent causes of personnel unavailability in military units, being associated with significant morbidity and degradation of their operational effectiveness. The disease is usually...

An Outbreak of Norovirus Gastroenteritis in a Long-term Care Hospital: Relation with Tube Feeding

An Outbreak of Norovirus Gastroenteritis in a Long-term Care Hospital: Relation with Tube Feeding

Outbreak of Norovirus Gastroenteritis Associated With Ice Cream Contaminated by Frozen Raspberries From China-Minnesota, United States, 2016.

Norovirus is the etiology for about 60% of foodborne outbreaks identified in Minnesota. Contamination of food during preparation by food handlers is by far the most common cause of these outbreaks. Norovirus outbreaks due to commercially distributed foods are rarely reported in the United States, and only 2 have been previously identified in Minnesota, both due to oysters. In August 2016, we investigated an outbreak of norovirus gastroenteritis in Minnesota that was linked to consumption of commercially distributed ice cream at multiple venues. Sanitarians from local public health agencies visited the facilities involved for follow-up, and case-control studies were conducted. The outbreak was identified by linking multiple independent illness reports to a centralized foodborne illness complaint system and subsequently confirmed though genotyping of stool specimens. A total of 15 cases from 4 venues were reported. Raspberry chocolate chip ice cream was statistically associated with illness in 2 analytic studies (6 of 7 cases vs 0 of 7 controls; odds ratio, undefined; P = .005). Norovirus GII.17[P17] (GII.17 Kawasaki) strains from case stool specimens matched norovirus found in frozen raspberries imported from China that were used to make the implicated ice cream. To our knowledge, this is the first norovirus outbreak due to commercially distributed frozen berries identified in the United States. To detect norovirus outbreaks associated with commercially distributed food vehicles, investigators should thoroughly investigate all norovirus outbreaks (including stool testing and genotyping), coordinate complaint and response activities across agencies and jurisdictions, and consider testing food for norovirus when appropriate.

Clinical pictures, treatments, and resource use of norovirus gastroenteritis in long-term care facilities: a survey with a chart review in Japan

BackgroundOutbreaks of norovirus infection can have detrimental impacts on long-term care facilities. This study investigated the incidence, clinical picture, treatment and resource use of norovirus gastroenteritis in long-term care facilities.MethodsNineteen facilities in Osaka and Kyoto, Japan participated in questionnaire surveys conducted between 2009 and 2011 regarding the incidence of norovirus gastroenteritis. From clinical charts, the characteristics, symptoms, and treatment of infected residents were analyzed. Total drug cost per infected resident was calculated by multiplying the unit price for each drug by the daily dose and the number of days administered and summing the costs for each drug (USD 1 = JPY 100).ResultsOver the 3-year period, 8 outbreaks of norovirus gastroenteritis occurred in 6 facilities. The mean clinical course of 107 infected residents in five facilities that granted permission to examine patients’ medical records was 4 days, with all but one resident presenting with vomiting and/or diarrhea, and 84 (79%) also presenting with associated symptoms. Of 107 infected residents, 72 (67%) were isolated. The proportion of infected residents isolated varied from 50 to 100% depending on the facility. Of the infected residents, 81 (76%) received some type of medication, the most common being infusion (67 patients, 63%) and antibiotics (30 patients, 28%). The median total cost of all drugs administered was USD 4.4, and the median drug cost per infected resident per day was USD 2.0. Total drug cost over the entire treatment period was the highest for antibiotics, at USD 8.6.ConclusionClinical course was similar to those of norovirus cases examined at other long-term care facilities. The majority of infected residents received some type of medication. Although the economic burden was not large, not a few infected residents were given antibiotics, which are ineffective for norovirus.

Norovirus detection in environmental samples in norovirus outbreaks in closed and semi-closed settings

Environmental surfaces are a potential vehicle for the transmission of norovirus outbreaks in closed and semi-closed settings. Testing of environmental samples may help control outbreaks. To assess the level of environmental contamination by norovirus in acute gastroenteritis outbreaks in closed or semi-closed settings (nursing homes, schools, kindergartens, youth accommodations, hospitals and social health centres) in the Barcelona region between January 2017 and March 2019. A prospective surveillance study was carried out. Environmental samples (529) were collected in 46 of the 50 outbreaks of acute norovirus gastroenteritis from environmental surfaces of common areas, bathrooms and kitchens in closed and semi-closed settings when the outbreak was notified and 10 days later. Instructions for taking environmental samples were distributed to public health inspectors. Norovirus was detected by reverse transcription polymerase chain reaction. Environmental samples were positive for norovirus in 31 (67.4%) outbreaks. Norovirus was most frequently detected on elevator buttons (4/17, 24%), toilet handles (16/66, 24%) and handrail bars (7/34, 21%). Positive samples from the first sampling were mainly found in bathrooms and greater viral persistence in the second sampling was found on elevator buttons and TV remote controls. Nursing homes were the setting with the most types of environmental surfaces contaminated (82% in first samples and 55% in second samples). The probability of virus detection is independent of the time between notification of the outbreak or symptom onset and sample collection. Our results suggest possible defects in cleaning protocols and disinfection in closed and semi-closed settings.

某驻训部队一起因生活用水污染引起的诺如病毒胃肠炎调查分析

某驻训部队一起因生活用水污染引起的诺如病毒胃肠炎调查分析

Detection of Norovirus from fresh and vended Periwinkles (Tympanotonus fuscatus var radula) in Nigeria

The major enteric viral pathogens comprising the Rotavirus, Norovirus, Adenovirus and Astrovirus are commonly implicated in outbreaks of viral gastroenteritis and can be found in several fecally contaminated milieu. Consumption of oysters and other sea foods have been incriminated in food borne outbreaks of Norovirus gastroenteritis. As there are paucity of data from Nigeria, on the contraction of viral gastroenteritis via consumption of seafood, this study was aimed at detecting these viruses from commercially vended periwinkles, a popularly consumed seafood delicacy in Nigeria. Between October 2018 and March 2019 fresh periwinkle samples were collected by convenience sampling, from traders in two (2) major markets in Lagos State, Nigeria. At each market, 10 samples were collected and pooled weekly and tested for concurrent presence of four enteric viruses using Enzyme Immuno-Assay Combo kit. Results obtained were analysed using descriptive statistics and Chi square at α0.05. Out of the 48 batches analysed, only the Norovirus was found in seven (7) batches at a prevalence of 14.6% in the study area. The highest rate of detection occurred in December 2018 from Oyingbo market, while the highest monthly rate occurred in Ikotun market. No statistically significant association was found in Norovirus detection from periwinkles at the two market sites (χ2 = 0.167, p = 0.6826). Similarly, no statistically significant association in the rate of Norovirus detection and the month of sample collection (χ2 = 8.864, p = 0.115, df = 5). This is the first report of Noroviruses from food sources in Nigeria. The results obtained from this study indicated that periwinkles serve as reservoirs of Norovirus and can be a potential source for the outbreak of gastroenteritis and diarrhea disease in the study area.Keywords: Periwinkles; Norovirus; Foodborne gastroenteritis

Sentinel physicians network in Reunion: an essential and key actor for epidemiological surveillance

Abstract Issue/Problem The surveillance of seasonal infectious diseases in Reunion is based on a Sentinel physician’s network of 52 volunteers, which is coordinated by the Indian Ocean regional office. Description of the problem The main objectives are to identify and monitor outbreaks of infectious diseases like influenza-like-illness (ILI) gastroenteritis, dengue, and conjunctivitis. A virological surveillance set up to characterize circulating respiratory viruses from a nasal swab collected by the physicians. Swabs are tested by RT-PCR for influenza in the reference laboratory. Results The surveillance demonstrated that the influenza season during the 2018 austral winter ran from September to October. More than 55 000 consultations related to ILI were estimated. The virological surveillance confirmed the circulation of A (H3N2) principally in 2018. The physician’s network identified the first cases of chikungunya in Réunion Island in 2005 and data collected by this physician’s network provide the epidemic trends with weekly estimation’s of total numbers of consultations in the Reunion Island. More than 25 000 community consultations of dengue-like-illness have been estimated. The physician’s network took part in the surveillance of conjunctivitis outbreak in 2016 and identified an outbreak of norovirus gastroenteritis in Reunion Island in 2007 and 2012. Lessons This network is an essential tool for disease surveillance and control activities. Key messages The network provides provisional virological and severity data on circulating influenza several months before the onset of influenza season in mainland France. The network is engaged and active which enables the early detection of any emergent diseases.

Outbreaks of Norovirus and Acute Gastroenteritis Associated with British Columbia Oysters, 2016-2017.

Two outbreaks of norovirus and acute gastroenteritis took place in Canada between November 2016 and April 2017. Both outbreaks were linked to oysters from British Columbia (BC) coastal waters. This paper describes the multi-agency investigations to identify the source and control the outbreak. Public health officials conducted interviews to determine case exposures. Traceback was conducted by collecting oyster tags from restaurants and analyzing them to determine the most common farms. Oyster samples were collected from case homes, restaurants, and harvest sites and tested for the presence of norovirus. Potential environmental pollution sources were investigated to identify the source of the outbreak. Four hundred and 49 cases were identified as part of the two outbreak waves. The oysters were traced to various geographically dispersed farms in BC coastal waters. Twelve farms were closed as a result of the investigations. No environmental pollution sources could be identified as the cause of the outbreak. Similarities in the timeframe, genotype, and geographic distribution of identified oyster farms indicate that they may have been one continuous event. Genotype data indicate that human sewage contamination was the likely cause of the outbreak, although no pollution source was identified.

The coordinating role of the human norovirus minor capsid protein VP2 is essential to functional change and nuclear localization of the major capsid protein VP1.

Global outbreaks of norovirus (NOV) gastroenteritis are associated with the most prevalent genotype, GII.4. Mutations in the protruding domain 2 (P2 domain) of the norovirus major capsid protein (VP1) result in the emergence of various NOV variants, however, it is unclear whether the minor capsid protein (VP2) also affects the generation of VP1 variants. In this study, using a human 293T expression system, we investigated the interactions of VP1 and VP2 of three GII.4 strains, focusing on the changes in expression and cellular localization. We found that co-transfection with VP1 and VP2 leads to a significant increase in expression of both proteins compared to that in cells transfected with VP1 or VP2 alone. In contrast to VP1 expressed in the absence of VP2, which was dispersed throughout the cytosol, VP2 expressed in the absence of VP1 was found to be located in the nucleus. This could be attributed to a predicted specific nuclear localization signal found in this gene. When both proteins were expressed, VP1 was found together with VP2 in the nucleus. These results thus suggest that the VP2 of GII.4 NOVs affects the function and cellular location of VP1 and that, with the cooperation of VP2, VP1 could play a critical role in affecting cell functions by impairing the downstream transcriptional signaling and chromatin remodeling in the cell nuclei.

Country-wide surveillance of norovirus outbreaks in the Portuguese Army, 2015–2017

IntroductionGastrointestinal infections are among the most common foodborne and waterborne diseases in military populations, with direct implications in operational efficiency and force readiness. Through the surveillance system of reportable acute...

Analysis of frozen strawberries involved in a large norovirus gastroenteritis outbreak using next generation sequencing and digital PCR

Virus-contaminated frozen berries have been frequently identified as cause of foodborne disease outbreaks. To provide new tools for virus detection and characterization in berries, next generation sequencing (NGS) and reverse transcription-digital PCR (RT-dPCR) techniques were tested here with strawberries previously involved in a large-scale norovirus (NoV) gastroenteritis outbreak in Germany. By NGS, about 29 million sequence reads were generated, which mainly showed identities to sequences from the plant matrix and from the bacterial flora. Most abundant virus sequences originated from plant-specific viruses, whereas sequences with high identity to human viruses were rare. Only two sequence reads showed homologies to human NoV. They were identical to GII.P16/GII.13 NoV sequences from patients and a strawberry sample independently analyzed during the outbreak. Quantification of the GII NoV RNA of the berries using RT-dPCR confirmed a low mean virus amount of 185 copies/25 g, which is similar to independently assessed RT-qPCR results (257 copies/25 g). The study shows that identification of human-pathogenic viruses in naturally contaminated frozen berries is possible using NGS technologies. However, the method needs to be further optimized in order to enable convenient and reproducible detection of a low amount of human-pathogenic virus sequences in a background of highly abundant nucleic acids of other sources.

Waterborne Norovirus outbreak at a seaside resort likely originating from municipal water distribution system failure.

In May 2016 a Norovirus (NoV) gastroenteritis outbreak involved a high school class visiting a seaside resort near Taormina (Mascali, Sicily). Twenty-four students and a teacher were affected and 17 of them showed symptoms on the second day of the journey, while the others got ill within the following 2 days. Symptoms included vomiting, diarrhoea and fever, and 12 students required hospitalisation. Stool samples tested positive for NoV genome by Real-Time polymerase chain reaction assay in all 25 symptomatic subjects. The GII.P2/GII.2 NoV genotype was linked to the outbreak by ORF1/ORF2 sequence analysis. The epidemiological features of the outbreak were consistent with food/waterborne followed by person-to-person and/or vomit transmission. Food consumed at a shared lunch on the first day of the trip was associated to illness and drinking un-bottled tap water was also considered as a risk factor. The analysis of water samples revealed the presence of bacterial indicators of faecal contamination in the water used in the resort as well as in other areas of the municipal water network, linking the NoV gastroenteritis outbreak to tap water pollution from sewage leakage. From a single water sample, an amplicon whose sequence corresponded to the capsid genotype recovered from patients could be obtained.

Erratum to: The Presence of Norovirus and Adenovirus on Environmental Surfaces in Relation to the Hygienic Level in Food Service Operations Associated with a Suspected Gastroenteritis Outbreak.

Norovirus (NoV) gastroenteritis outbreaks appear frequently in food service operations (FSOs), such as in restaurants and canteens. In this study the presence of NoV and adenovirus (AdV) genomes was investigated on the surfaces of premises, especially in kitchens, of 30 FSOs where foodborne gastroenteritis outbreaks were suspected. The objective was to establish a possible association between the presence of virus genomes on surfaces and a visual hygienic status of the FSOs. NoV genome was found in 11 and AdV genome in 8 out of 30 FSOs. In total, 291 swabs were taken, of which 8.9% contained NoV and 5.8% AdV genome. The presence of NoV genomes on the surfaces was not found to associate with lower hygiene level of the premises when based on visual inspection; most (7/9) of the FSOs with NoV contamination on surfaces and a completed evaluation form had a good hygiene level (the best category). Restaurants had a significantly lower proportion of NoV-positive swabs compared to other FSOs (canteens, cafeteria, schools etc.) taken together (p = 0.00014). The presence of a designated break room for the workers was found to be significantly more common in AdV-negative kitchens (p = 0.046). Our findings suggest that swabbing is necessary for revealing viral contamination of surfaces and emphasis of hygiene inspections should be on the food handling procedures, and the education of food workers on virus transmission.

An outbreak of foodborne norovirus gastroenteritis linked to a restaurant in Melbourne, Australia, 2014.

IntroductionIn May 2014 an outbreak of norovirus occurred among patrons of a restaurant in Melbourne, Australia. Investigations were conducted to identify the infectious agent, mode of transmission and source of illness, and to implement controls to prevent further transmission.MethodsA retrospective case-control study was conducted to test the hypothesis that food served at the restaurant between 9 and 15 May 2014 was the vehicle for infection. A structured questionnaire was used to collect demographic, illness and food exposure data from study participants. To ascertain whether any food handlers had experienced gastroenteritis symptoms and were a possible source of infection, investigators contacted and interviewed staff who had worked at the restaurant between 9 and 16 May 2014.ResultsForty-six cases (including 16 laboratory-confirmed cases of norovirus) and 49 controls were interviewed and enrolled in the study. Results of the analysis revealed a statistically significant association with illness and consumption of grain salad (OR: 21.6, 95% CI: 1.8–252.7, P = 0.015) and beetroot dip (OR: 22.4, 95% CI: 1.9–267.0, P = 0.014). An interviewed staff member who reported an onset of acute gastrointestinal illness on 12 May 2014 had prepared salads on the day of onset and the previous two days.DiscussionThe outbreak was likely caused by person-to-food-to-person transmission. The outbreak emphasizes the importance of the exclusion of symptomatic food handlers and strict hand hygiene practices in the food service industry to prevent contamination of ready-to-eat foods and the kitchen environment.

Emergence of new recombinant noroviruses GII.p16-GII.4 and GII.p16-GII.2, France, winter 2016 to 2017.

An early increase in outbreaks of norovirus gastroenteritis characterised at the French National Reference Centre occurred this winter season. They were concurrent with an unusual pattern of circulating strains, with three predominant genotypes: the re-emergent variant GII.P4 2009-GII.4 2012 found in 28% of norovirus outbreaks and two new emergent recombinant strains GII.P16-GII.4 2012 and GII.P16-GII.2 never before observed in France, found in 24% and 14% of norovirus outbreaks, respectively.

The Presence of Norovirus and Adenovirus on Environmental Surfaces in Relation to the Hygienic Level in Food Service Operations Associated with a Suspected Gastroenteritis Outbreak

Norovirus (NoV) gastroenteritis outbreaks appear frequently in food service operations (FSOs), such as in restaurants and canteens. In this study the presence of NoV and adenovirus (AdV) genomes was investigated on the surfaces of premises, especially in kitchens, of 30 FSOs where foodborne gastroenteritis outbreaks were suspected. The objective was to establish a possible association between the presence of virus genomes on surfaces and a visual hygienic status of the FSOs. NoV genome was found in 11 and AdV genome in 8 out of 30 FSOs. In total, 291 swabs were taken, of which 8.9% contained NoV and 5.8% AdV genome. The presence of NoV genomes on the surfaces was not found to associate with lower hygiene level of the premises when based on visual inspection; most (7/9) of the FSOs with NoV contamination on surfaces and a completed evaluation form had a good hygiene level (the best category). Restaurants had a significantly lower proportion of NoV-positive swabs compared to other FSOs (canteens, cafeteria, schools etc.) taken together (p = 0.00014). The presence of a designated break room for the workers was found to be significantly more common in AdV-negative kitchens (p = 0.046). Our findings suggest that swabbing is necessary for revealing viral contamination of surfaces and emphasis of hygiene inspections should be on the food handling procedures, and the education of food workers on virus transmission.