Outbreaks Of Acute Viral Gastroenteritis Research Articles

Norovirus outbreaks in long-term care facilities in Catalonia from 2017 to 2018

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).

Wastewater-Based Epidemiology of Enteric Viruses and Surveillance of Acute Gastrointestinal Illness Outbreaks in a Resource-Limited Region.

Acute gastrointestinal illness (AGI) continues to be an important cause of morbidity and mortality among all ages. This study applied the principles of wastewater-based epidemiology for the preventive identification of potential outbreaks of acute viral gastroenteritis and hepatitis A by analyzing the presence of human enteric viruses in influents of small municipal wastewater treatment plants (WWTPs) handling domestic sewage, together with public health reports of acute diarrheal and hepatitis A disease in Costa Rica during 2013. Raw wastewater samples were collected during four seasonal periods with different rainfall levels. The presence of five human enteric viruses (rotavirus A, norovirus GI, norovirus GII, enterovirus, and hepatitis A virus) was studied by endpoint and real-time polymerase chain reaction in influents of five WWTPs. Cases of AGI were analyzed using historical public health reports of endemic levels and quartile ranges for each administrative and territorial area where the WWTPs are located and for its surrounding counties. A tendency for a higher rate of positive viral tests was present 1 week before an increase of AGI cases. Epidemiological weeks categorized as Outbreak (above the 75th percentile) and Success (below the 25th percentile) showed statistically significant differences in terms of positive viral test rates (Wilcoxon test, P = 0.05). Virological monitoring of wastewater in small WWTPs is an appropriate model for epidemiological surveillance of diarrheal and hepatitis A diseases in low- and middle-resource countries.

Epidemiology of Aichi virus in fecal samples from outpatients with acute gastroenteritis in Northwestern Spain

BackgroundIn recent years, Aichi virus (AiV) has been involved in acute viral gastroenteritis outbreaks. However, the common pathogenesis of AiV releases more in subclinical infections underestimating the impact of AiV in human health. ObjectivesThe present study describes the presence and genetic diversity of AiV in patients with gastroenteritis in Northwestern Spain. Study design: A total of 2667 stool samples, obtained between July 2010 and June 2011, from diarrheic outpatients were studied for detection and molecular characterization of AiV using PCR techniques followed by sequencing and phylogenetic analyses. ResultsThe virus was detected in 124 (5.0%) of the samples among all age groups. Coinfections were also detected, from the 124 positive samples, 72 (58.1%) were positive only for AiV, whereas mixed contaminations with Norovirus genogroup I or genogroup II, Sapovirus, or other enteric pathogens were detected in 52 (41.9%) samples. A total of 70 positive samples could be genotyped, being characterized as genotype A (58.6%) or B (41.4%). AiV was detected from August to April, being the highest number of AiV positive samples detected during autumn and winter seasons. ConclusionsThis survey remarks the importance of emerging enteric viruses in patients who require medical assistance, and offers more information about the real importance of AiV as gastroenteritis agent.

Norovirus Detection at Oualidia Lagoon, a Moroccan Shellfish Harvesting Area, by Reverse Transcription PCR Analysis.

Norovirus (NoV) is the leading cause of acute viral gastroenteritis outbreaks in the world. These outbreaks are frequently associated with bivalve shellfish consumption, particularly because these products are often eaten raw or only slightly cooked. In Morocco, regulations concerning the acceptable levels of enteric bacteria indicator organisms in these products have been put in place. However, these regulations do not take into account the risk of viral contamination, and many gastroenteritis outbreaks have been linked to the ingestion of bivalve shellfish from areas that comply with the current food safety criteria. The aim of this study was to investigate NoV presence in shellfish samples (n = 104) collected at four sites owcff Oualidia lagoon (Moroccan Atlantic coast) from November 2015 to February 2017. Samples were analysed using real-time RT-PCR in accordance with the ISO 15216-2 method. NoVs of the genogroup II were detected in 7% of samples that were all collected during the winter months. Moreover, 71% of NoV-positive samples were harvested at sites upstream of the lagoon. These results highlight the need of regularly monitoring viral contamination in bivalve shellfish to limit the risk of viral gastroenteritis outbreaks.

Acute Viral Gastroenteritis: Viruses Other Than Norovirus

Acute Viral Gastroenteritis: Viruses Other Than Norovirus Abstract. Norovirus is the leading cause of acute viral gastroenteritis. Norovirus is highly contagious, thus outbreaks of norovirus in hospitals and long-term care facilities are feared. Usually, stool samples of patients with a potentially viral gastroenteritis are first checked for the presence of norovirus. In recent years, sapovirus and astrovirus were increasingly reported as cause of acute gastroenteritis. Outbreaks of acute viral gastroenteritis caused by sapovirus or astrovirus are hardly distinguishable from those caused by norovirus because of a similar clinical presentation. Molecular analyses of stool specimen are needed for accurate diagnosis of the viral cause of acute gastroenteritis. It is worth to further investigate stool samples of patients suspected of acute viral gastroenteritis not only for norovirus, but also for sapovirus and astrovirus.

Prevalence, levels and seasonal variations of human enteric viruses in six major rivers in Alberta, Canada

The prevalence and seasonal variation of 7 viruses in 6 major rivers in Alberta were assessed using a combination of qPCR, cell culture and integrated cell culture with qPCR (ICC-qPCR). Water samples were collected monthly from rivers at different sites upstream and downstream of major urban centers. Seven viruses including rotavirus, adenovirus, astrovirus, norovirus, sapovirus, JC virus and enterovirus, were detected in at least one of the water samples at each site using qPCR. Rotavirus was most common with concentration ranging from 2.3 to 4.5 log10 genomic equivalent (GE) copies/L. Norovirus, sapovirus, astrovirus, adenoviruses and JC virus peaked during the winter (November to March). Viruses were most prevalent at the Bow River sampling site downstream of the City of Calgary, followed by the North Saskatchewan River site downstream of the City of Edmonton and the Red Deer River site downstream of the City of Red Deer. The detection rates and quantity of viruses had significant difference in the sampling sites between upstream and downstream of major urban centers (p < 0.001). 14% of the samples tested positive using viral culture indicating the presence of infectious viruses in river. Sequencing analysis identified human rotavirus in 75% of the samples collected from downstream versus 37% of the samples collected from upstream sites (p < 0.02). Multivariate binary regression showed that human activity in watersheds is a significant determinant of viruses in Alberta's Rivers. The discharge from wastewater treatment plants may be the possible sources of viral contamination. Seasonal coincidence of acute viral gastroenteritis outbreaks and monthly peak occurrence of enteric viruses in river water implies potential impact of waterborne viruses on human health.

The prevalence of non-GII.4 norovirus genotypes in acute gastroenteritis outbreaks in Jinan, China.

Noroviruses (NoVs) are the leading cause of acute viral gastroenteritis outbreaks. From June 2015 to March 2017, fifteen outbreaks of acute gastroenteritis (AGE) were reported to the Jinan Center for Disease Control and Prevention in China. To identify the circulating NoV genotypes associated with outbreaks in Jinan, China, 414 specimens from the 15 outbreaks were collected and analyzed for the causative viruses, and phylogenetic analysis was performed on the NoV-positive strains. The NoV detection rate was 57.5% (238/414), and a total of 14 outbreaks were caused by NoVs (eight by infection with genogroup II (GII), five by mixed infection with GI and GII, and one by mixed infection with GII and rotavirus (RoV)-A). A total of 75 NoV sequences were obtained from 13 NoV-positive outbreaks and classified into seven genotypes (38 GII.17, 13 GII.2, 4 GII.3, 4 GII.1, 10 GI.6, 5 GI.5 and 1 GI.3), while GII.4 was not identified. The most prevalent genotype changed yearly during the 2015–2017 period. Phylogenetic analysis demonstrated that these NoV genotypes had high homology with the strains circulating worldwide, especially strains from Asian countries and cities. Our study illustrated that multiple non-GII.4 NoV genotypes were prevalent in outbreaks of AGE in Jinan, China. Year-round surveillance of multiple NoV genotypes could help health authorities reduce the impact of NoV outbreaks on public health.

Economic costs of outbreaks of acute viral gastroenteritis due to norovirus in Catalonia (Spain), 2010-2011.

BackgroundTo determine the direct and indirect costs of outbreaks of acute viral gastroenteritis (AVG) due to norovirus in closed institutions (hospitals, social health centers or nursing homes) and the community in Catalonia in 2010–11.MethodsInformation on outbreaks were gathered from the reports made by epidemiological surveillance units. Direct costs (medical visits, hospital stays, drug treatment, sample processing, transport, diagnostic tests, monitoring and control of the outbreaks investigated) and indirect costs (lost productivity due to work absenteeism, caregivers time and working hours lost due to medical visits) were calculated.ResultsTwenty-seven outbreaks affecting 816 people in closed institutions and 74 outbreaks affecting 1,940 people in the community were detected. The direct and indirect costs of outbreaks were € 131,997.36 (€ 4,888.79 per outbreak) in closed institutions and € 260,557.16 (€ 3,521.04 per outbreak) in community outbreaks. The cost per case was € 161.76 in outbreaks in closed institutions and € 134.31 in community outbreaks. The main costs were surveillance unit monitoring (€ 116,652.93), laboratory diagnoses (€ 119,950.95), transport of samples (€ 69,970.90), medical visits (€ 25,250.50) and hospitalization (€ 13,400.00).ConclusionsThe cost of outbreaks of acute viral gastroenteritis due to norovirus obtained in this study was influenced by the number of people affected and the severity of the outbreak, which determined hospitalizations and work absenteeism. Urgent reporting of outbreaks would allow the implementation of control measures that could reduce the numbers affected and the duration of the illness and thus the costs derived from them.

Molecular characteristics of norovirus in 3 outbreak-episodes of gastroenteritis in Zhejiang from 2008 to 2009

To study the molecular characteristic of norovirus in 3 outbreaks of gastroenteritis in Zhejiang province. During January 2008 and December 2009, fecal specimens of patients were collected from 3 outbreaks of acute viral gastroenteritis. Noroviruses were detected by Real-time RT-PCR. Part of the positive samples were randomly selected and detected by RT-PCR. PCR products were sequenced. Sequence analysis was undertaken based on partial sequence of RNA dependent RNA polymerase (RdRp) and capsid protein gene. Some positive samples were amplified by 3'RACE (rapid amplification of cDNA 3'ends), 3200 bp in length. The exact whole ORF2, ORF3 and 3'untranslation regions (UTR) gene of norovirus were identified. There were in total 3 outbreaks of viral gastroenteritis caused by norovirus being reported. A total of 62 stools were obtained from cases with acute gastroenteritis. Noroviruses were detected in 41 cases including 27 strains of genogroup I norovirus and 9 strains of genogroup II norovirus, 5 strains of genogroup I + II norovirus. Four genotypes including GI.8, GII.b, GI.2/GI.6 recombination together with co-infection of GI.8 and GII.b were detected. Norovirus was confirmed as the major cause of outbreaks of viral gastroenteritis in Zhejiang province and multiple genotype of norovirus were identified from the outbreaks. It was the first time to have found a recombinant of GI.6 capsid and GI.2 polymerase norovirus as well as the co-infection of GI.8 and GII.b norovirus in the same sample.

Viral Etiology of Diarrhea Outbreaks in Child Care Centers

Infectious Diseases| May 01 2009 Viral Etiology of Diarrhea Outbreaks in Child Care Centers AAP Grand Rounds (2009) 21 (5): 55. https://doi.org/10.1542/gr.21-5-55 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Viral Etiology of Diarrhea Outbreaks in Child Care Centers. AAP Grand Rounds May 2009; 21 (5): 55. https://doi.org/10.1542/gr.21-5-55 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search toolbar search search input Search input auto suggest filter your search All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Topics: child day care centers, diarrhea, disease outbreaks, stool specimen Source: Lyman WH, Walsh JF, Kotch JB, et al. Prospective study of etiologic agents of acute gastroenteritis outbreaks in child care centers. J Pediatr. 2009;154(2):253–257; doi:10.1016/j.jpeds.2008.07.057 Investigators from the University of North Carolina-Chapel Hill and the Centers for Disease Control in Atlanta prospectively studied the etiology of outbreaks of acute viral gastroenteritis (AGE) in North Carolina child care centers (CCC) between October 2005 and March 2007. AGE was defined as at least two episodes of diarrhea within 24 hours and an outbreak was defined as two or more children with diarrhea in the same classroom on the same day. The etiology of a confirmed outbreak was defined as at least two positive fecal specimens for the same virus, or if multiple viruses were identified, at least two environmental samples testing positive for the same virus as that detected in the fecal sample. Outbreak information and clinical and environmental specimens were collected from child care health consultants, county health departments, and the North Carolina State Laboratory for Public Health. Stool samples were screened for rotavirus, astrovirus, adenovirus, and two calicviruses, norovirus and sapovirus, using both real-time reverse transcription-polymerase chain reaction (RT-PCR) and PCR. RT-PCR was used for genotyping. If no viral cause was identified, bacterial cultures were performed for Yersinia, Salmonella, Shigella, and Campylobacter. Fifty-three of the 94 statewide health consultants participated in the first season and 41 in the second. Twenty-nine outbreaks were identified, 23 between October and May in the first season (2005–2006), and six between November and mid-March in the second season (2006–2007). Seventy-seven fecal specimens were collected (mean 2.7 samples per outbreak). Sixty percent of the children were 12 to 36 months of age and 36% were <12 months of age. A single virus was determined to be the etiology for 13 (45%) outbreaks (rotavirus in five, astrovirus and norovirus each in three, and sapovirus in two). Of these, three had multiple viruses detected in fecal specimens but only a single virus was detected in two environmental samples. In three other outbreaks multiple viruses were detected in fecal specimens, but no single etiologic agent could be identified based on environmental sampling. In four outbreaks only a single virus-positive fecal specimen was detected. In nine (31%) outbreaks no virus was identified. In these, bacterial cultures were also negative. Rotavirus outbreaks occurred between February and April while norovirus outbreaks occurred throughout the study period. Environmental swabs were collected from 22 outbreaks that had a positive stool specimen, and 13 (59%) of these tested positive for a virus. In 12 outbreaks the virus was the same as in stool specimens. The authors conclude that viruses are the major cause of AGE outbreaks in CCC and that widespread environmental contamination occurs during such outbreaks. Dr. Rathore has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device. Almost half of the outbreaks of AGE in this study could be... You do not currently have access to this content.

Aetiology and epidemiology of viral gastroenteritis outbreaks in Catalonia (Spain) in 2004–2005

Background Acute infectious gastroenteritis causes substantial morbidity and economic loss. Objective The aetiology, epidemiology, and clinical features of acute viral gastroenteritis outbreaks reported during 1 year in Catalonia were investigated. Study Design This was a population-based study in which enzyme immunoassay and reverse transcriptase-polymerase chain reaction (RT-PCR) techniques were used to determine the presence of virus in stool specimens from outbreaks clinically and epidemiologically compatible with a viral aetiology and negative for bacteria, parasites and toxins. Results Sixty outbreaks affecting 1791 people were evaluated. Fifty-five outbreaks were positive for norovirus, four were positive for norovirus and other microorganisms (adenovirus, astrovirus, S. Typhimurium and V. parahaemolyticus in one each). Thirty-seven percentage of the outbreaks occurred in collective catering; 18.3% in nursing homes; 10% in hospitals and long-term-care facilities. Foodborne transmission accounted for 50% of outbreaks. Norovirus genotype GGII.4 accounted for 42% of all the outbreaks, being more prevalent in nursing homes, hospital and long-term-care facilities. Conclusions The large number of norovirus outbreaks and resulting health service demand and absenteeism indicate that acute gastroenteritis caused by norovirus is an important health problem in Catalonia. Preventive measures should target education and control of food handlers, and immediate specific control measures should be adopted in institutions.

Correlation of norovirus variants with epidemics of acute viral gastroenteritis in Hong Kong

Norovirus (NV) (formerly called Norwalk-like virus) is the most common etiological agent of acute viral gastroenteritis outbreaks worldwide. Recent reports have shown that two new GII.4 variants caused epidemics in Europe. To investigate if it is also the case in Hong Kong, a molecular epidemiological study was undertaken between January 2002 and June 2005. During this period, there was a substantial increase in acute cases of gastroenteritis caused by NV. Phylogenetic analysis showed that GII.2 and GII.4 are the major circulating genotypes. Two new GII.4 variants (variants C and D) were identified in 2002 and 2004, which quickly became the predominant strains. They were almost identical to the variants causing epidemics in Europe recently. Since geographically distinct areas were involved within a short period of time, it is possible that GII.4 has a particular propensity for causing pandemics.

Antigenic relatedness among the Norwalk‐like agents by serum antibody rises

The Norwalk, Snow Mountain (SMA), and Hawaii agents are etiologically associated with separate outbreaks of acute viral gastroenteritis. Previous cross-challenge of volunteers, immune electron microscopy, and/or enzyme-immunoassay analysis suggested that these agents are antigenically distinct. We examined paired sera from human volunteers challenged with these agents for the presence of homologous and heterologous serum antibody titer rises to the agents. Two-way cross-reactions occurred between Hawaii agent and SMA. A one-way cross-reaction occurred between Norwalk agent and SMA, as volunteers challenged with Norwalk agent had heterologous serum antibody titer rises to SMA, but the reverse did not occur. The Norwalk and Hawaii agents had minimal cross-reaction, with only one volunteer challenged with Hawaii agents having a heterologous rise to Norwalk agent. These observations indicate varying degrees of antigenic relatedness among these agents.