Outbreak Of Norovirus Gastroenteritis Research Articles

Widespread Outbreak of Norovirus Gastroenteritis among Evacuees of Hurricane Katrina Residing in a Large "Megashelter" in Houston, Texas: Lessons Learned for Prevention

After Hurricane Katrina, an estimated 200,000 persons were evacuated to the Houston metropolitan area, >27,000 of whom were housed in 1 large "megashelter," the Reliant Park Complex. We investigated an outbreak of gastroenteritis reported among the evacuees who resided in the Reliant Park Complex to assess the spread of the infectious agent, norovirus, and to implement and evaluate the effectiveness of interventions used for control. Public health authorities conducted surveillance of gastroenteritis among evacuees treated at the Reliant Park Medical Clinic during 2-12 September 2005. Basic demographic and clinical data were recorded. Specimens of stool and vomitus were collected and tested for bacteria, parasites, and viruses. Shelter census data were used to estimate the daily incidence of disease. During a period of 11 days, >1000 patients were treated at the clinic for gastroenteritis, which accounted for 17% of all clinic visits. Norovirus was the sole enteric pathogen identified, but multiple different strains were involved. Among the evacuees residing in the Reliant Park Complex, the incidence of gastroenteritis was estimated to be 4.6 visits per 1000 persons per day, and among the evacuees who resided there for 9 days, 1 (4%) of 24 persons would have been ill. Intensive public health measures were promptly instituted but did not definitively slow the progression of the outbreak of norovirus gastroenteritis. Our investigation underscores the difficulties in managing such outbreaks in crowded settings and the need for rapid, sensitive laboratory assays to detect norovirus. Additional research is needed to establish more effective measures to control and prevent this highly contagious gastrointestinal illness.

Molecular Epidemiology of Norovirus Outbreaks in Norway during 2000 to 2005 and Comparison of Four Norovirus Real-Time Reverse Transcriptase PCR Assays

During the period from January 2000 to August 2005 a total of 204 outbreaks of norovirus gastroenteritis were diagnosed at the Norwegian Institute of Public Health. A clear increase in the norovirus activity was seen in healthcare institutions during the winter seasons. Polymerase sequence analysis of norovirus strains from 122 outbreaks showed that 112 were caused by GII strains (91.8%). Two norovirus variants seen during the study period-GIIb and GII.4-were predominant between January 2000 and September 2002, whereas GII.4 was predominant from September 2002 onward. The highest norovirus activity was seen during the 2002-2003 and 2004-2005 seasons with the emergence of new GII.4 variants. This study describes the molecular epidemiology of norovirus strains circulating in Norway during the five previous seasons and compares four norovirus real-time reverse transcriptase PCR assays. A suitable assay for routine diagnostics is suggested.

Four outbreaks of norovirus gastroenteritis after consuming raspberries, Sweden, June-August 2006

So far in 2006, in Sweden, there have been four outbreaks of norovirus gastroenteritis where raspberries were the suspected vehicle of infection. The first outbreak occurred at the end of June,

Management of a Gastroenteritis Outbreak Due to Norovirus

ISSUE: An increasing number of outbreaks of Norovirus (NV) gastroenteritis are occurring in hospitals but there are few published descriptions of how to manage a NV outbreak in hospital settings. We describe the process we used to contain a NV outbreak. PROJECT: An outbreak of acute gastroenteritis involving both healthcare workers (HCWs) and patients suggested NV as the possible cause. Accordingly, stool specimens were sent to reference laboratories for NV polymerase chain reaction (PCR) assays. A multidisciplinary ad hoc committee, which included representatives from Hospital Administration, Admitting, Infection Control and Environmental Services was formed, and met 3 to 5 times per week during the outbreak. Following a literature review, a case definition was developed. Nursing Managers faxed a list of symptomatic HCWs and patients to Infection Control daily using a standardized form. Affected HCWs were furloughed until 48 hours after their last episode of vomiting or diarrhea. Symptomatic patients were cohorted on several “affected wards” where universal glove and gown precautions were used. A cardiology ward with the greatest number of cases was closed to admissions, and later vacated and cleaned thoroughly. A 1:10 bleach solution was used to disinfect rooms of affected patients, communal bathrooms and kitchen areas. RESULTS: The outbreak lasted approximately 6 weeks and affected 165 health care workers and 124 patients. Of the 30 stool specimens tested, 3 were positive for NV. Twelve elective cardiac procedures were cancelled or delayed when the cardiology ward was closed. Problems encountered included: long turn-around times to obtain NV PCR results, difficulties in communicating rapidly changing information to HCWs, lack of sufficient telemetry beds during closure of the cardiology ward, food service workers who reported for work despite having diarrhea, and complaints by some HCWs regarding the strong odor of bleach. LESSONS LEARNED: Frequent meetings of the ad hoc multidisciplinary committee, close attention to hand hygiene, isolation precautions, cleaning procedures, closure of a ward with ongoing transmission, and daily active surveillance for signs and symptoms of viral gastroenteritis were important measures in containing the outbreak.

Rapid control of norovirus gastroenteritis outbreak in an acute paediatric ward

To provide a practical action plan for effective infection control of norovirus outbreak in acute paediatric wards. We report the infection control measures that were implemented to terminate and to prevent nosocomial spread of norovirus gastroenteritis in an open-designed paediatric ward. Nine children, one visitor, and one medical student were affected in a norovirus gastroenteritis outbreak in an acute paediatric ward. Vomiting was the main presenting symptom. The outbreak was rapidly terminated three days after implementation of stringent infection control measures and there was no second wave of attack. These measures included strict contact precautions, prompt isolation and cohorting of symptomatic patients, vigorous environmental cleansing with concentrated disinfectant (hypochlorite solution 1000 ppm), meticulous handling of waste products, and efficient contact tracing of exposed patients, family members, and medical students. Prompt implementation of stringent infection control measures and contact tracing can rapidly terminate the norovirus outbreak and prevent a second wave of infection. Children with unexplained vomiting and those with contact history of gastroenteritis should be properly triaged, isolated, and investigated for possible infective causes, including norovirus-induced gastroenteritis.

Rapid control of norovirus gastroenteritis outbreak in an acute paediatric ward

Abstract Aim: To provide a practical action plan for effective infection control of norovirus outbreak in acute paediatric wards. Methods: We report the infection control measures that were implemented to terminate and to prevent nosocomial spread of norovirus gastroenteritis in an open‐designed paediatric ward. Results: Nine children, one visitor, and one medical student were affected in a norovirus gastroenteritis outbreak in an acute paediatric ward. Vomiting was the main presenting symptom. The outbreak was rapidly terminated three days after implementation of stringent infection control measures and there was no second wave of attack. These measures included strict contact precautions, prompt isolation and cohorting of symptomatic patients, vigorous environmental cleansing with concentrated disinfectant (hypochlorite solution 1000 ppm), meticulous handling of waste products, and efficient contact tracing of exposed patients, family members, and medical students. Conclusion: Prompt implementation of stringent infection control measures and contact tracing can rapidly terminate the norovirus outbreak and prevent a second wave of infection. Children with unexplained vomiting and those with contact history of gastroenteritis should be properly triaged, isolated, and investigated for possible infective causes, including norovirus‐induced gastroenteritis.

Molecular Subtyping and the Transformation of Public Health

Molecular Subtyping and the Transformation of Public Health

P14.11 Infection Control for Norovirus Gastroenteritis Outbreak in Acute Open-Designed Paediatric Ward

P14.11 Infection Control for Norovirus Gastroenteritis Outbreak in Acute Open-Designed Paediatric Ward

An outbreak of norovirus gastroenteritis associated with wedding cakes

We sought to determine the source of a norovirus outbreak among attendees of 46 weddings taking place during a single weekend. Norovirus-compatible illness was experienced by 332 (39%) of wedding guests surveyed; the outbreak affected up to 2700 persons. Illness was associated with eating wedding cake provided by a bakery common to the weddings (adjusted RR 4.5, P<0.001). A cake requiring direct hand contact during its preparation accounted for the majority of illness. At least two bakery employees experienced norovirus-compatible illness during the week preceding the weddings. Identical sequence types of norovirus were detected in stool specimens submitted by two wedding guests, a wedding hall employee, and one of the ill bakery employees. It is likely that one or more food workers at the bakery contaminated the wedding cakes through direct and indirect contact. These findings reinforce the necessity of proper food-handling practices and of policies that discourage food handlers from working while ill.

Norovirus contamination found in oysters worldwide

Noroviruses (Norwalk-like viruses) are recognized as major causes of acute gastroenteritis worldwide. Outbreaks of norovirus gastroenteritis are often associated with consumption of oysters. In this study, oysters imported into Hong Kong from 11 countries over a 3-year period were screened by RT-PCR. Overall, 53 out of 507 (10.5%) samples were positive for norovirus-RNA, and a wide variety of strains were found. Two novel genetic clusters were detected, which could indicate novel human or animal norovirus strains. However, whether these two new clusters are of human or animal origin is not known. Thirteen outbreaks, in which oysters were implicated as the source of infection were investigated: Norovirus RNA sequences could be detected in oysters from six outbreaks, but only in one outbreak the strains isolated from patients and oysters matched (>98% homology). Therefore, RT-PCR was of use in detecting norovirus contamination of oysters implicated in an outbreak, but was less useful in demonstrating an actual molecular epidemiological link with human cases. It was shown that contamination by noroviruses could be demonstrated in oysters worldwide, and therefore oysters may serve as an important vehicle for introducing novel norovirus strains.

Norovirus Transmission on Cruise Ship

An outbreak of norovirus gastroenteritis affected passengers on two consecutive cruises of ship X and continued on 4 subsequent cruises despite a 1-week sanitization. We documented transmission by food and person-to-person contact; persistence of virus despite sanitization onboard, including introductions of new strains; and seeding of an outbreak on land.

Oyster-associated outbreaks of Norovirus gastroenteritis in Singapore

Outbreaks of gastroenteritis associated with the consumption of raw imported half-shelled frozen oysters occurred in Singapore between 16 Dec 2003 and 04 Jan 2004. A total of 305 cases were reported with clinical symptoms of diarrhoea (94%), abdominal cramps (72%), vomiting (69%) and fever (54%). The median incubation period was 30.8 h and the duration of illness was 2–3 days. The overall relative risk of oyster consumption was 14.1 (95% CI: 8.3–24.0, P<0.001). Stool and oyster samples tested negative for common bacterial pathogens, including Vibrio parahaemolyticus. However, stool samples were positive for the presence of Norovirus group II RNA via RT PCR while oyster samples indicated the presence of Norovirus particles by electron microscopy. The clinical and epidemiological features were suggestive of Norovirus gastroenteritis and were subsequently confirmed by laboratory tests of stools and implicated oysters. Steps have been taken to ensure that food outlets do not thaw frozen oysters and serve them raw.

An Outbreak of Norovirus Gastroenteritis on an Israeli Military Base

Noroviruses (NVs) are a predominant cause of viral gastroenteritis outbreaks, but they are difficult to identify because they cannot be cultivated in cell culture. Therefore, reverse-transcriptase polymerase chain reaction (RT-PCR) assays are widely used in the testing of clinical stool specimens for NV. However, testing of perianal swabs in the context of an outbreak is considered to be an insensitive method for identification of NV using the RT-PCR technique. An outbreak of acute gastroenteritis involving 159 soldiers on a training base of the Israel Defense Force in December 1999 allowed us to evaluate this identification method. An epidemiologic investigation, a sanitation survey and a case-control study of exposure to different food items served up to 48 h preceding the outbreak were conducted. Stool samples in the form of post-defecation perianal swabs were collected from 24 ill personnel and three non-ill food handlers. Swabs were tested for the presence of NV by RT-PCR assay. Epidemiologic data were consistent with a pointsource food-borne outbreak which was associated with consumption of fresh vegetable salad in the base mess hall (OR = 4.38, 95% CI 1.51-13.35). Both epidemiologic and clinical features were suggestive of gastroenteritis caused by NV, and upon laboratory analysis perianal swabs from four of 24 cases were positive for NV. The combination of practical specimen collection with perianal post-defecation swabs, and the utilization of a molecular epidemiology approach, can simplify the rapid identification of outbreaks caused by NVs.

Asymptomatic and symptomatic excretion of noroviruses during a hospital outbreak of gastroenteritis.

During an investigation of a hospital outbreak of norovirus gastroenteritis identified as being caused by a recombinant genogroup II (rGII-3a) strain, fecal specimens collected from asymptomatic staff and patients were tested by nested PCR. A GII-4 norovirus strain, the predominant strain associated with outbreaks in hospitals over the last few years, was detected in 26 and 33% of asymptomatic staff and patients, respectively. No rGII-3a (Harrow/Mexico) norovirus strains were detected in the samples of asymptomatic staff or patients.

Diversity of enterovirus sequences detected in oysters by RT-heminested PCR

Oysters harvested in western France, from five sites associated with outbreaks of food-borne norovirus gastroenteritis between February 2000 and March 2001, were assayed for enterovirus RNA by reverse transcriptase-heminested polymerase chain reaction (RT-heminested PCR). Forty percent (21/52) of shellfish samples (pool of seven oysters) were contaminated by enteroviruses. Infectious coxsackieviruses serotype A21 were isolated from three of these positive samples. Amplicons corresponding to 65 base sequences in the 5′ untranslated region of the enteroviral genome were analyzed by direct sequencing. Interpretable results were obtained from 18 amplicons, but mixtures of sequences confused the results from 3 samples. Sequences isolated from samples from the different sites were different but similarities were observed between sequences detected in shellfish from two sites at different dates. Sequences were also compared to sequences of human, bovine and porcine enteroviruses. Both human and animal origins of enterovirus contamination of shellfish seemed likely.

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

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. 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. Three regions (England and Wales, Germany, and the Netherlands) had sustained epidemiological and viral characterisation data from 1995 to 2002. In all three, we noted a striking increase in norovirus outbreaks in 2002 that coincided with the detection and emergence of a new predominant norovirus variant of genogroup II4, which had a consistent mutation in the polymerase gene. Eight of nine regions had an annual peak in 2002 and the new genogroup II4 variant was detected in nine countries. Also, the detection of the new variant preceded an atypical spring and summer peak of outbreaks in three countries. Our data from ten European countries show a striking increase and unusual seasonal pattern of norovirus gastroenteritis in 2002 that occurred concurrently with the emergence of a novel genetic variant. In addition to showing the added value of an international network for viral gastroenteritis outbreaks, these observations raise questions about the biological properties of the variant and the mechanisms for its rapid dissemination.

Nosocomial outbreak of norovirus gastroenteritis and investigation of ABO histo-blood group type in infected staff and patients

The blood groups were analysed of staff and patients ( N=45) infected during two nosocomial outbreaks of norovirus gastroenteritis at a German University hospital. Persons with O phenotype were significantly less affected than was expected from the normal distribution of blood group types in Southwest Germany (OR 2.45; 95% CI 1.22–4.95; P=0.01).

GIP006 Nosocomial outbreak of Norovirus gastroenteritis and investigation of ABO histo-blood group type in infected staff and patients

Noroviruses, an important cause of acute gastroenteritis, possess a highly divergent genome which was classified into five genogroups and dozens of genotypes. However, changes in genotype distribution over time were poorly understood, particularly in developing countries. We therefore conducted a molecular epidemiological study which characterized the norovirus strains detected in 4437 Nepalese children with acute diarrhea between November 2005 and January 2011 to gain insight into how their genotypes changed over time. Of the 356 samples positive for noroviruses, 277 (78%) were successfully genotyped into 22 capsid genotypes; GII.4 (n = 113), GII.3 (n = 38) and GII.13 (n = 37) were the majority. Interestingly, GII.13 accounted for only 1.7% (4/230) between 2005 and 2008 (period 1) but increased substantially to 26.2% (33/126) between 2009 and 2011 (period 2). Phylogenetic analysis of the VP1 nucleotide sequences of 35 GII.13 strains indicated that they clustered into two lineages named NPL2008 and NPL2009 to which two period 1 strains and 33 period 2 strains belonged, respectively. Lineage NPL2009 contained GII.13 strains that were detected in a large-scale gastroenteritis outbreak in Germany in 2012. Both Nepalese and German VP1 sequences carried two substitutions, H378N and V394Q, in the putative histo-blood group antigen (HBGA)-binding sites. As to the polymerase genotypes of Nepalese strains, the period 1 strains possessed GII.Pm, but the period 2 strains possessed GII.P13, GII.P16, and GII.P21. Together with recent reports on the predominance of GII.P13/GII.13 and GII.P16/GII.13 in India and GII.P16/GII.13 in European countries, this study predicts that genotype GII.13 which was previously regarded as a minor genotype has a potential to become an epidemiologically important genotype.

Book Reviews

To study norovirus gastroenteritis infection among residents and health care workers (HCWs) during an outbreak in a nursing home by investigating the attack rate and positive diagnostic rate for norovirus by reverse transcription–polymerase chain reaction (RT-PCR).All members in a Chang Gung Memorial Hospital–affiliated nursing home from November 17, 2006, to November 25, 2006, including 236 residents and 125 HCWs, whose available medical records were available were consecutively included in the retrospective analysis. Fecal specimens of symptomatic residents and HCWs were tested for norovirus by RT-PCR. In addition, routine stool analysis and a stool culture study were conducted to identify the bacterial and parasitic agents. The fecal specimens of asymptomatic residents and HCWs were tested only for norovirus by RT-PCR.The outbreak was controlled within 9 days during the outbreak period. There were 51 symptomatic cases, 41 residents and 10 HCWs, during the norovirus outbreak. The odds ratio (OR) of the attack rate in the residents was approximately 2.4 times higher than that in the HCWs (OR: 2.4; 95% confidence interval [CI]: 1.2–5.0; P = .015). Norovirus was detected in 59 (30.6%) of 193 residents and in 11 (10.5%) of 105 HCWs who provided stool specimens for the study by RT-PCR. The OR of the positive diagnostic rate for norovirus by RT-PCR in the residents was approximately 3.8 times higher than that in the HCWs (OR: 3.8; 95% CI: 1.9–7.5; P < .001).During an outbreak of norovirus gastroenteritis in a nursing home, the infection can be easily transmitted from person to person and affects both residents and HCWs. In addition, residents had a higher risk of norovirus gastroenteritis infection than HCWs.

Outbreaks of infectious ectromelia in laboratory and wild mice

The Journal of Pathology and BacteriologyVolume 37, Issue 2 p. 253-256 Research Article Outbreaks of infectious ectromelia in laboratory and wild mice C. A. McGaughey, C. A. McGaughey Departments of Bacteriology and Pathology, Victoria University of ManchesterSearch for more papers by this authorRaymond Whitehead, Raymond Whitehead Departments of Bacteriology and Pathology, Victoria University of ManchesterSearch for more papers by this author C. A. McGaughey, C. A. McGaughey Departments of Bacteriology and Pathology, Victoria University of ManchesterSearch for more papers by this authorRaymond Whitehead, Raymond Whitehead Departments of Bacteriology and Pathology, Victoria University of ManchesterSearch for more papers by this author First published: 1933 https://doi.org/10.1002/path.1700370207Citations: 8AboutRelatedInformationPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessClose modalShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume37, Issue21933Pages 253-256 RelatedInformation RecommendedEpidemiology of acute gastroenteritis outbreaks caused by Noroviruses in Okayama, JapanMasako Hamano, Mitsutaka Kuzuya, Ritsushi Fujii, Hajime Ogura, Masao Yamada, Journal of Medical VirologyTwo gastroenteritis outbreaks caused by sapovirus in Shenzhen, ChinaJinjin Wang MD, Yuan Li PhD, Xiangxu Kong MD, Huiying Li PhD, Qing Zhang BA, Miao Jin PhD, Yongjie Wang PhD, Zhaojun Duan PhD, Journal of Medical VirologyMolecular epidemiology of norovirus gastroenteritis outbreaks in North Carolina, United States: 1995–2000F.C. Tseng, J.S. Leon, J.N. MacCormack, J.-M. Maillard, C.L. Moe, Journal of Medical VirologyMolecular epidemiology of norovirus outbreaks in Argentina, 2013‐2018Juan I. Degiuseppe, Leslie Barclay, Karina A. Gomes, Veronica Costantini, Jan Vinjé, Juan A. Stupka, Journal of Medical VirologyMolecular epidemiology of norovirus gastroenteritis outbreaks in New Zealand from 2002–2009Gail E. Greening, Joanne Hewitt, Malet Rivera-Aban, Dawn Croucher, Journal of Medical Virology