1
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Johnson SS, Jackson KC, Mietchen MS, Sbai S, Schwartz EJ, Lofgren ET. Excess Risk of COVID-19 to University Populations Resulting from In-Person Sporting Events. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18168260. [PMID: 34444008 PMCID: PMC8394285 DOI: 10.3390/ijerph18168260] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 12/19/2022]
Abstract
Background: One of the consequences of COVID-19 has been the cancelation of collegiate sporting events. We explore the impact of sports on COVID-19 transmission on a college campus. Methods: Using a compartmental model representing the university, we model the impact of influxes of 10,000 visitors attending events and ancillary activities (dining out, visiting family, shopping, etc.) on 20,000 students. We vary the extent visitors interact with the campus, the number of infectious visitors, and the extent to which the campus has controlled COVID-19 absent events. We also conduct a global sensitivity analysis. Results: Events caused an increase in the number of cases ranging from a 25% increase when the campus already had an uncontrolled COVID-19 outbreak and visitors had a low prevalence of COVID-19 and mixed lightly with the campus community to an 822% increase where the campus had controlled their COVID-19 outbreak and visitors had both a high prevalence of COVID-19 and mixed heavily with the campus community. The model was insensitive to parameter uncertainty, save for the duration a symptomatic individual was infectious. Conclusion: Sporting events represent a threat to the health of the campus community. This is the case even in circumstances where COVID-19 seems controlled both on-campus and among the general population.
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Affiliation(s)
- Stephanie S. Johnson
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA 99164, USA; (S.S.J.); (K.C.J.); (M.S.M.)
| | - Katelin C. Jackson
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA 99164, USA; (S.S.J.); (K.C.J.); (M.S.M.)
| | - Matthew S. Mietchen
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA 99164, USA; (S.S.J.); (K.C.J.); (M.S.M.)
| | - Samir Sbai
- School of Electrical Engineering and Computer Science, Washington State University, Pullman, WA 99164, USA;
| | - Elissa J. Schwartz
- Department of Mathematics and Statistics, Washington State University, Pullman, WA 99164, USA;
- School of Biological Sciences, Washington State University, Pullman, WA 99164, USA
| | - Eric T. Lofgren
- Paul G. Allen School for Global Health, Washington State University, Pullman, WA 99164, USA; (S.S.J.); (K.C.J.); (M.S.M.)
- Correspondence:
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2
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Kirchner M, Goulter RM, Chapman BJ, Clayton J, Jaykus LA. Cross-Contamination on Atypical Surfaces and Venues in Food Service Environments. J Food Prot 2021; 84:1239-1251. [PMID: 33545714 DOI: 10.4315/jfp-20-314] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 02/02/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT Cross-contamination of raw food to other surfaces, hands, and foods is a serious issue in food service. With individuals eating more meals away from home, contracting a foodborne illness from a food service establishment is an increasing concern. However, most studies have concentrated on hands or food contact surfaces and neglected atypical and unusual surfaces (surfaces that are not typically identified as a source of cross-contamination) and venues. This review was conducted to identify atypically cross-contaminated surfaces and atypical venues where cross-contamination could occur that have not been examined thoroughly in the literature. Most surfaces that could be at risk for cross-contamination are frequently touched, are rarely cleaned and sanitized, and can support the persistence and/or growth of foodborne pathogens. These surfaces include menus, spice and condiment containers, aprons and coveralls, mobile devices and tablets, and money. Venues that are explored, such as temporary events, mobile vendors, and markets, are usually limited in space or infrastructure, have low compliance with proper hand washing, and provide the opportunity for raw and ready-to-eat foods to come into contact with one another. These factors create an environment in which cross-contamination can occur and potentially impact food safety. A more comprehensive cleaning and sanitizing regime encompassing these surfaces and venues could help mitigate cross-contamination. This review highlights key surfaces and venues that have the potential to be cross-contaminated and have been underestimated or not fully investigated. These knowledge gaps indicate where further work is needed to fully understand the role of these surfaces and venues in cross-contamination and how it can be prevented. HIGHLIGHTS
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Affiliation(s)
- Margaret Kirchner
- Department of Food, Bioprocessing and Nutrition Science, North Carolina State University, Raleigh, North Carolina 27695
| | - Rebecca M Goulter
- Department of Food, Bioprocessing and Nutrition Science, North Carolina State University, Raleigh, North Carolina 27695
| | - Benjamin J Chapman
- Department of Agricultural and Human Sciences, North Carolina State University, Raleigh, North Carolina 27695
| | | | - Lee-Ann Jaykus
- Department of Food, Bioprocessing and Nutrition Science, North Carolina State University, Raleigh, North Carolina 27695
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Li M, Yang Y, Lu Y, Zhang D, Liu Y, Cui X, Yang L, Liu R, Liu J, Li G, Qu J. Natural Host-Environmental Media-Human: A New Potential Pathway of COVID-19 Outbreak. ENGINEERING (BEIJING, CHINA) 2020; 6:1085-1098. [PMID: 33520330 PMCID: PMC7834166 DOI: 10.1016/j.eng.2020.08.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 07/21/2020] [Accepted: 08/07/2020] [Indexed: 05/05/2023]
Abstract
Identifying the first infected case (patient zero) is key in tracing the origin of a virus; however, doing so is extremely challenging. Patient zero for coronavirus disease 2019 (COVID-19) is likely to be permanently unknown. Here, we propose a new viral transmission route by focusing on the environmental media containing viruses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or RaTG3-related bat-borne coronavirus (Bat-CoV), which we term the "environmental quasi-host." We reason that the environmental quasi-host is likely to be a key node in helping recognize the origin of SARS-CoV-2; thus, SARS-CoV-2 might be transmitted along the route of natural host-environmental media-human. Reflecting upon viral outbreaks in the history of humanity, we realize that many epidemic events are caused by direct contact between humans and environmental media containing infectious viruses. Indeed, contacts between humans and environmental quasi-hosts are greatly increasing as the space of human activity incrementally overlaps with animals' living spaces, due to the rapid development and population growth of human society. Moreover, viruses can survive for a long time in environmental media. Therefore, we propose a new potential mechanism to trace the origin of the COVID-19 outbreak.
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Affiliation(s)
- Miao Li
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yunfeng Yang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yun Lu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Dayi Zhang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yi Liu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Xiaofeng Cui
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Lei Yang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Ruiping Liu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Jianguo Liu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Guanghe Li
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiuhui Qu
- School of Environment, Tsinghua University, Beijing 100084, China
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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4
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Bhatta MR, Marsh Z, Newman KL, Rebolledo PA, Huey M, Hall AJ, Leon JS. Norovirus outbreaks on college and university campuses. JOURNAL OF AMERICAN COLLEGE HEALTH : J OF ACH 2020; 68:688-697. [PMID: 31084526 PMCID: PMC11268439 DOI: 10.1080/07448481.2019.1594826] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 11/30/2018] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
Objective: To describe norovirus outbreaks at colleges and universities. Participants: None. Conducted September 2016 to March 2018. Methods: College and university norovirus outbreaks reported to the US National Outbreak Reporting System (NORS, 2009-2016) or published and indexed by EMBASE, PubMed, and Web of Science (1985-2017) were analyzed. Results: Seventy-seven norovirus outbreaks were reported to NORS and 23 were identified in the systematic literature review. Outbreaks occurred more frequently during the beginning of the school year (September-February). NORS outbreaks were more often spread by person-to-person transmission (61%) and, in published outbreaks, by food (57%). The reported exposures of published outbreaks were campus dining (n = 8) and ill food service workers (n = 7). Higher attack rates were associated with smaller on-campus population size, social networks or residences, and specific food exposures. Common control measures were communal area disinfection and health/hygiene education. Conclusions: Recommendations summarized to prevent and control norovirus outbreaks at colleges or universities.
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Affiliation(s)
- Manasa R Bhatta
- College of Arts and Sciences, Emory University, Atlanta, Georgia, USA
| | - Zach Marsh
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA
| | - Kira L Newman
- Internal Medicine Residency Program, University of Washington, Seattle, Washington, USA
| | - Paulina A Rebolledo
- Hubert Department of Global Health, Emory University Rollins School of Public Health, Atlanta, Georgia, USA
- Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Michael Huey
- Student Health Services, Emory University and Department of Family and Preventive Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Aron J Hall
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- Hubert Department of Global Health, Emory University Rollins School of Public Health, Atlanta, Georgia, USA
| | - Juan S Leon
- Hubert Department of Global Health, Emory University Rollins School of Public Health, Atlanta, Georgia, USA
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5
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Rushton SP, Sanderson RA, Reid WDK, Shirley MDF, Harris JP, Hunter PR, O'Brien SJ. Transmission routes of rare seasonal diseases: the case of norovirus infections. Philos Trans R Soc Lond B Biol Sci 2020; 374:20180267. [PMID: 31104607 DOI: 10.1098/rstb.2018.0267] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Norovirus (NoV) is the most commonly recognized cause of acute gastroenteritis, with over a million cases globally per year. While usually self-limiting, NoV poses a substantial economic burden because it is highly contagious and there are multiple transmission routes. Infection occurs through inhalation of vomitus; faecal-oral spread; and food, water and environmental contamination. While the incidence of the disease is predictably seasonal, much less is known about the relative contribution of the various exposure pathways in causing disease. Additionally, asymptomatic excretion and viral shedding make forecasting disease burden difficult. We develop a novel stochastic dynamic network model to investigate the contributions of different transmission pathways in multiple coupled social networks representing schools, hospitals, care-homes and family households in a community setting. We analyse how the networks impact on transmission. We used ward-level demographic data from Northumberland, UK to create a simulation cohort. We compared the results with extant data on NoV cases from the IID2 study. Connectivity across the simulated cohort was high. Cases of NoV showed marked seasonality, peaking in early winter and declining through the summer. For the first time, we show that fomites and food appear to be the most important exposure routes in determining the population burden of disease. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'. This theme issue is linked with the earlier issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'.
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Affiliation(s)
- Stephen P Rushton
- 1 Modelling, Evidence and Policy Research Group, School of Natural and Environmental Science, Newcastle University , Newcastle upon Tyne NE1 7RU , UK
| | - Roy A Sanderson
- 1 Modelling, Evidence and Policy Research Group, School of Natural and Environmental Science, Newcastle University , Newcastle upon Tyne NE1 7RU , UK
| | - William D K Reid
- 2 Ecology Research Group, School of Natural and Environmental Science, Newcastle University , Newcastle upon Tyne NE1 7RU , UK
| | - Mark D F Shirley
- 1 Modelling, Evidence and Policy Research Group, School of Natural and Environmental Science, Newcastle University , Newcastle upon Tyne NE1 7RU , UK
| | - John P Harris
- 3 Public Health and Policy, University of Liverpool , Liverpool L69 3GL , UK.,4 National Institute for Health Research, Health Protection Research Unit in Gastrointestinal Infections , Liverpool L69 3GL , UK
| | - Paul R Hunter
- 4 National Institute for Health Research, Health Protection Research Unit in Gastrointestinal Infections , Liverpool L69 3GL , UK.,5 Norwich Medical School, University of East Anglia , Norwich 33 NR4 7TJ , UK
| | - Sarah J O'Brien
- 1 Modelling, Evidence and Policy Research Group, School of Natural and Environmental Science, Newcastle University , Newcastle upon Tyne NE1 7RU , UK.,2 Ecology Research Group, School of Natural and Environmental Science, Newcastle University , Newcastle upon Tyne NE1 7RU , UK.,4 National Institute for Health Research, Health Protection Research Unit in Gastrointestinal Infections , Liverpool L69 3GL , UK
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6
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Abstract
On 16 March 2018, a nursing home notified a possible acute gastroenteritis outbreak that affected 11 people. Descriptive and case-control studies and analysis of clinical and environmental samples were carried out to determine the characteristics of the outbreak, its aetiology, the transmission mechanism and the causal food. The extent of the outbreak in and outside the nursing home was determined and the staff factors influencing propagation were studied by multivariate analysis. A turkey dinner on March 14 was associated with the outbreak (OR 4.22, 95% CI 1.11-16.01). Norovirus genogroups I and II were identified in stool samples. The attack rates in residents, staff and household contacts of staff were 23.49%, 46.22% and 22.87%, respectively. Care assistants and cleaning staff were the staff most frequently affected. Cohabitation with an affected care assistant was the most important factor in the occurrence of cases in the home (adjusted OR 6.37, 95% CI 1.13-36.02). Our results show that staff in close contact with residents and their household contacts had a higher risk of infection during the norovirus outbreak.
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7
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8
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Teng JLL, Martelli P, Chan WM, Lee HH, Hui SW, Lau CCY, Tse H, Yuen KY, Lau SKP, Woo PCY. Two novel noroviruses and a novel norovirus genogroup in California sea lions. J Gen Virol 2018; 99:777-782. [PMID: 29722646 DOI: 10.1099/jgv.0.001071] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In this study, two novel noroviruses (NoVs) were discovered from faecal samples from California sea lions from an oceanarium in Hong Kong, and named California sea lion NoV 1 (Csl/NoV1) and California sea lion NoV 2 (Csl/NoV2). Whole-genome sequencing showed that the genome organization and amino acid motifs of both Csl/NoV1 and Csl/NoV2 were typical of those of other NoVs in their open reading frames (ORFs). Csl/NoV1 possessed only 52.6-52.8 % amino acid identity in VP1 to the closest matches in genogroup GII. Therefore, Csl/NoV1 should constitute a novel genogroup of NoV. Shifting of the phylogenetic position of Csl/NoV1 in the RdRp, VP1 and VP2 trees was observed, which may have been due to recombination events and/or biased mutations. Csl/NoV2 possessed 55.4-56.2 % amino acid identity in VP1 to its closest relatives in genogroup GVI, which means that it represents a new genotype in genogroup GVI. Further studies will reveal what diseases these NoVs can cause in marine mammals.
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Affiliation(s)
- Jade L L Teng
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong SAR
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong SAR
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong SAR
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
| | | | - Wan-Mui Chan
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
| | - Hwei Huih Lee
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
| | | | - Candy C Y Lau
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
| | - Herman Tse
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong SAR
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong SAR
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong SAR
| | - Kwok-Yung Yuen
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong SAR
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong SAR
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong SAR
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong SAR
| | - Susanna K P Lau
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong SAR
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong SAR
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong SAR
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong SAR
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
| | - Patrick C Y Woo
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The University of Hong Kong, Hong Kong SAR
- State Key Laboratory of Emerging Infectious Diseases, Hong Kong SAR
- Research Centre of Infection and Immunology, The University of Hong Kong, Hong Kong SAR
- Carol Yu Centre for Infection, The University of Hong Kong, Hong Kong SAR
- Department of Microbiology, The University of Hong Kong, Hong Kong SAR
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9
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Cavanagh K, Johnstone T, Huhtinen E, Najjar Z, Lorentzos P, Shadbolt C, Shields J, Gupta L. Foodborne Illness Outbreak Investigation in a High-Profile Sports Club. SPORTS MEDICINE-OPEN 2017. [PMID: 28647923 PMCID: PMC5483224 DOI: 10.1186/s40798-017-0088-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
A foodborne illness outbreak involving an elite sports team was investigated by a public health unit in Sydney, Australia. An epidemiological association was established between gastrointestinal illness and the consumption of food supplied by an external caterer, with a lamb meal most strongly associated with illness. Genetically identical Salmonella isolates were identified from clinical specimens, residual food items, and an environmental swab taken from the catering premises. The training schedule and other club operations were significantly affected by this outbreak. Increased susceptibility due to regular shared activities and the potential for significant impact upon performance indicates that sports clubs must ensure that food suppliers comply with the highest standards of hygiene. Collaboration with public health authorities assists in source identification and prevention of further transmission.
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Affiliation(s)
- Kwendy Cavanagh
- Sydney Local Health District Public Health Unit, King George V Building, Missenden Road, Camperdown, NSW, 2050, Australia
| | - Travers Johnstone
- Sydney Local Health District Public Health Unit, King George V Building, Missenden Road, Camperdown, NSW, 2050, Australia
| | - Essi Huhtinen
- Sydney Local Health District Public Health Unit, King George V Building, Missenden Road, Camperdown, NSW, 2050, Australia
| | - Zeina Najjar
- Sydney Local Health District Public Health Unit, King George V Building, Missenden Road, Camperdown, NSW, 2050, Australia
| | | | - Craig Shadbolt
- New South Wales (NSW) Food Authority, 6 Avenue of the Americas, Newington, NSW, 2127, Australia
| | - John Shields
- New South Wales (NSW) Food Authority, 6 Avenue of the Americas, Newington, NSW, 2127, Australia
| | - Leena Gupta
- Sydney Local Health District Public Health Unit, King George V Building, Missenden Road, Camperdown, NSW, 2050, Australia.
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10
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Abstract
PURPOSE OF REVIEW Runner's diarrhea is an acute exercise-induced diarrhea. Usually, this is not a pathological situation but it can affect performance. This review focuses on the discussion of the main causes of runner's diarrhea and nutritional recommendations to prevent it. RECENT FINDINGS Although based on limited data, multiple transportable carbohydrate intake during exercise instead of glucose alone can be recommended for preventing the urge to defecate and (possibly) diarrhea. Additionally, avoiding ingestion of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is related to a lower incidence of reported gastrointestinal problems. There is, however, still no study that associates FODMAPs and runner's diarrhea. Gluten-free diets seem to have no impact on exercise-induced intestinal damage and there is no evidence to recommend this diet for the prevention of diarrhea in nonceliac athletes. SUMMARY The main causes of diarrhea in runners are ischemic, mechanical, and nutritional factors. For the prevention of diarrhea, it has been recommended that dehydration and the ingestion of fiber, fat, protein, high concentrated carbohydrate beverages, FODMAPs, caffeine, bicarbonate, and nonsteroidal anti-inflammatory drugs be avoided. However, the causes of diarrhea and nutritional strategies to prevent it are based on limited research and more studies are definitely needed.
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11
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Woods JW, Calci KR, Marchant-Tambone JG, Burkhardt W. Detection and molecular characterization of norovirus from oysters implicated in outbreaks in the US. Food Microbiol 2016; 59:76-84. [DOI: 10.1016/j.fm.2016.05.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 05/13/2016] [Accepted: 05/13/2016] [Indexed: 10/21/2022]
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12
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Navarro G, Sala RM, Segura F, Arias C, Anton E, Varela P, Peña P, Llovet T, Sanfeliu I, Canals M, Serrate G, Nogueras A. An Outbreak of Norovirus Infection in a Long-Term-Care Unit in Spain. Infect Control Hosp Epidemiol 2016; 26:259-62. [PMID: 15796277 DOI: 10.1086/502536] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractBackground:Norovirus belongs to the Caliciviridae family and causes outbreaks of infectious enteritis by fecal-oral transmission. In Spain, there have been few outbreaks reported due to this virus. We describe an outbreak on a long-term-care hospital ward.Methods:Cases were classified as probable, confirmed, and secondary. Stool cultures were performed. Polymerase chain reaction detection of norovirus was also performed.Results:The outbreak occurred from December 7 to 28, 2001, involving 60 cases (32 patients, 19 staff members, 8 patients' relatives, and 1 relative of a staff member). Most (82%) of the cases were female. The most frequently involved ages were 20 to 39 years for staff members and 70 to 89 years for patients. The incubation period of secondary cases in patients' families had a median of 48 hours (range, 1 to 7 days). Clinical symptoms included diarrhea (85%), vomiting (75%), fever (37%), nausea (23%), and abdominal pain (12%). Median duration of the disease was 48 hours (range, 1 to 7 days). All cases resolved and the outbreak halted with additional hygienic measures. Stool cultures were all negative for enteropathogenic bacteria and rotaviruses. In 16 of 23 cases, the norovirus genotype 2 antigen was detected.Conclusion:This outbreak of gastroenteritis due to norovirus genotype 2 affected patients, staff members, and their relatives in a long-term-care facility and was controlled in 21 days.
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Affiliation(s)
- Gemma Navarro
- Unitat d'Epidemiologia I Avaluacio, Corporacio Parc Tauli, Parc Tauli s/n, 08208 Sabadell, Barcelona, Spain.
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13
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Response to the Questions Posed by the Food Safety and Inspection Service, the Centers for Disease Control and Prevention, the National Marine Fisheries Service, and the Defense Health Agency, Veterinary Services Activity Regarding Control Strategies for Reducing Foodborne Norovirus Infections. J Food Prot 2016; 79:843-89. [PMID: 27296435 DOI: 10.4315/0362-028x.jfp-15-215] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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14
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Abstract
We investigated an outbreak of norovirus that affected students and teachers of a high school in Lleida, Spain through various transmission mechanisms. A case-control epidemiological study of the risk of disease and the relative importance of each mode of transmission was carried out. Cases and controls were selected from a systematic sample of students and teachers present at the school on 28 January. Faecal samples were taken from three food handlers and 16 cases. The influence of each factor was studied using the adjusted odds ratio (aOR) and the estimated population attributable risk (ePAR) with 95% confidence intervals (CI). We interviewed 210 people (42 cases, 168 controls). The proportion of symptoms in these individuals was nausea 78·6%, vomiting 59·5%, diarrhoea 45·2%, and fever 19·0%. The epidemic curve showed transmission for at least 4 days. The risk of disease was associated with exposure to food (aOR 5·8) in 66·1% of cases and vomit (aOR 4·7) in 24·8% of cases. Faecal samples from 11 patients and two food handlers were positive for norovirus GII.12 g. Vomit may co-exist with other modes of transmission in norovirus outbreaks and could explain a large number of cases.
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15
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Abstract
Risk is an inherent component of human existence, as is our creation of ways to avoid or minimize such risks. The formal process of assessing the likelihood and magnitude of risk, using that information to manage risk, and then communicating the process to others, forms the basis for risk analysis. This chapter provides an overview of the steps of risk analysis with a focus on risk assessment for foodborne viruses, particularly quantitative efforts that model and estimate the risks these viruses pose to human health. Most risk assessments in food and environmental virology performed in the last decade have focused on water, fresh produce, molluscan shellfish, and prepared foods. Recent examples of enteric virus risk modeling efforts are discussed in detail, as are several of the difficulties and intricacies of performing risk assessments for foodborne viruses compared to bacteria and other agents. This is a relatively new area of study, but one that will continue to grow as national and international agencies continue to adopt and require the methodology for food safety and the protection of human health.
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16
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Fischer SA. Emerging and Rare Viral Infections in Transplantation. TRANSPLANT INFECTIONS 2016. [PMCID: PMC7122901 DOI: 10.1007/978-3-319-28797-3_49] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Immunocompromised patients such as those undergoing solid organ or hematopoietic stem cell transplantation are at substantial risk for infection with numerous pathogens. Infections with cytomegalovirus (CMV), herpes simplex virus (HSV), Epstein–Barr virus (EBV), and human herpesvirus-6 (HHV-6) are well-described complications of transplantation. As viruses previously believed to be quiescent through widespread vaccination (e.g., measles and mumps) reemerge and molecular diagnostic techniques are refined, rare and emerging viral infections are increasingly diagnosed in transplant recipients. This chapter will review the clinical manifestations, diagnosis, and potential antiviral therapies for these viruses in the transplant population.
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17
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Arthur SE, Gibson KE. Physicochemical stability profile of Tulane virus: a human norovirus surrogate. J Appl Microbiol 2015; 119:868-75. [PMID: 26104882 DOI: 10.1111/jam.12878] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/12/2015] [Accepted: 06/13/2015] [Indexed: 11/28/2022]
Abstract
AIMS Human norovirus (HuNoV) is estimated to cause 19-21 million illnesses each year in the US. A major limitation in HuNoV research is the lack of an in vitro culture system; therefore, surrogate viruses including murine norovirus (MNV) and feline calicivirus (FCV) are used to study HuNoV. Here, we aim to establish the physiochemical properties of Tulane virus (TV)—a newer HuNoV surrogate. METHODS AND RESULTS For thermal inactivation, TV was exposed to 37°C for 2 h, and 56, 63 and 72°C for 30 min. For ethanol tolerance, TV was treated with 60, 70 and 90% ethanol at room temperature (RT) for 5 min. Tulane virus pH stability at pH 2, 3, 7, 9 and 10 was performed at RT for 90 min. At 37°C, there was no significant reduction in TV after 2 h. However, at 56, 63 and 72°C, D-values of 4·03, 1·18, and 0·24 min, were calculated respectively. The D-values obtained for TV ethanol tolerance were 1·46, 1·93, and 0·35 min at 60, 70 and 90% respectively. Less than 1 log10 plaque forming units (PFU) reduction was observed for TV at all pH levels except pH 10 where about a 2-log10 PFU reduction was observed. Tulane virus was also tolerant to chlorine disinfection on a solid surface with D-values of 15·82 and 5·42 min at 200 and 1000 ppm respectively. CONCLUSIONS Tulane virus is likely a suitable surrogate to study HuNoV thermal stability as well as ethanol tolerance below 90%. Tulane virus also is a promising surrogate to study HuNoV pH stability and chlorine tolerance. SIGNIFICANCE AND IMPACT OF THE STUDY Based on current work, in vitro studies demonstrate that TV is an overall more conservative and suitable surrogate for the study of HuNoV physicochemical properties.
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Affiliation(s)
- S E Arthur
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - K E Gibson
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
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Ryu S, You HJ, Kim YW, Lee A, Ko GP, Lee SJ, Song MJ. Inactivation of norovirus and surrogates by natural phytochemicals and bioactive substances. Mol Nutr Food Res 2014; 59:65-74. [PMID: 25410634 DOI: 10.1002/mnfr.201400549] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/13/2014] [Accepted: 11/13/2014] [Indexed: 01/11/2023]
Abstract
Human norovirus is the leading cause of sporadic gastroenteritis, which is responsible for more than 90% of all nonbacterial gastroenteritis outbreaks. While norovirus infections typically cause mild and self-limiting symptoms lasting 24-48 h, chronic persistent infections can cause severe symptoms. Although recent advances have been made in understanding the molecular characteristics of norovirus infection, no norovirus-specific antiviral drugs, or vaccines are available. Conventional intervention methods used to inactivate norovirus, such as treatment with disinfecting agents (e.g. ethanol, hypochlorite, and quaternary ammonium formulations), have shown a lack of efficacy against human norovirus when they are applied to foods and in food preparation processes. Therefore, alternative antiviral or inactivating agents such as phytochemicals have received attention as potential norovirus inhibitors due to their relatively low toxicity and lack of side effects, which allows them to be prepared as food-safe formulations. Evidence from studies using viral surrogates suggests that numerous phytochemicals and foods containing flavonoids and polyphenols have anti-norovirus activity, and future studies will be necessary to confirm the effectiveness of such compounds against human norovirus and the molecular mechanisms through which they produce antiviral effects.
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Affiliation(s)
- Seungbo Ryu
- Department of Biosystems and Biotechnology, Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
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Xue C, Fu Y, Zhu W, Fei Y, Zhu L, Zhang H, Pan L, Xu H, Wang Y, Wang W, Sun Q. An outbreak of acute norovirus gastroenteritis in a boarding school in Shanghai: a retrospective cohort study. BMC Public Health 2014; 14:1092. [PMID: 25335780 PMCID: PMC4221699 DOI: 10.1186/1471-2458-14-1092] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 10/13/2014] [Indexed: 02/07/2023] Open
Abstract
Background More than 200 students and teachers at a boarding school in Shanghai developed acute gastroenteritis in December, 2012. The transmission mode remained largely unknown. An immediate epidemiological investigation was conducted to identify it. Methods Using a retrospective cohort design, we investigated demographic characteristics, school environment, and previous contacts with people who had diarrhea and/or vomiting, drinking water conditions, recalls of food consumption in the school cafeteria, hand-washing habits and eating habits. Rectal swabs of the new cases and food handlers as well as water and food samples were collected to test potential bacteria and viruses. Norovirus was detected by real-time reverse transcription-polymerase chain reaction (RT-PCR). Results A total of 278 cases developed gastrointestinal symptoms in this outbreak, and the overall attack rate was 13.9%. The main symptoms included vomiting (50.0%), abdominal cramps (40.3%), nausea (27.0%), diarrhea (6.8%) and fever (6.8%). Twenty rectal swab samples were detected as Norovirus–positive, including 11 from student cases and 9 from asymptomatic food handlers (non-cases). Among environmental surface samples from the kitchen, 8 samples were also detected as Norovirus-positive. The genotypes of viral strains were the same (GII) in patients, asymptomatic food handlers and environmental surfaces. Other samples, including rectal swabs, water samples and food samples were negative for any bacteria and other tested viruses. Asymptomatic food handlers may have contaminated the cooked food during the food preparation. Conclusion The study detected that the outbreak was caused by Norovirus and should be controlled by thorough disinfection and excluding asymptomatic food handlers from food preparation. Early identification of the predominant mode of transmission in this outbreak was necessary to prevent new cases. Furthermore, good hygiene practices such as regular hand washing and efficient daily disinfection should be promoted to prevent such infection and outbreaks.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Qiao Sun
- Research Base of Key Laboratory of Surveillance and Early warning on Infectious Disease in China CDC, Shanghai Pudong District Center for Disease Control and Prevention, 3039 Zhangyang Road, Shanghai 200136, China.
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Abstract
Norovirus is the most frequent cause of acute infectious gastroenteritis and it is difficult to control in crowded environments like hospitals and nursing homes. Transmission depends on oral intake of virus deposited in the environment by infectious subjects. Data from volunteer studies indicate that virus concentrations in stool are highly variable, but systematic studies of the time-course of shedding and its individual variation are lacking. This paper quantifies norovirus shedding in a large population of 102 subjects, including asymptomatic shedders, and uses a longitudinal model to generalize shedding patterns. Enhanced surveillance for studies of transmission of norovirus in hospital outbreaks has yielded a considerable number of faecal samples from symptomatic and asymptomatic shedders, both from patients and staff. Norovirus concentrations were determined by real-time PCR. A quantitative dynamic model was fitted to the shedding data, in a multilevel Bayesian framework, to study the time-course of shedding and its variation. The results indicate that shedding in asymptomatic subjects is similar to that in symptomatic infections, both showing considerable variation in peak levels (average 105-109 /g faeces) as well as duration of virus shedding (average 8-60 days). Patients appear to shed higher numbers of virus than staff, for slightly longer durations, but the differences are too small to be significant. Given equal shedding, the greater contribution of symptomatic cases to transmission must be caused by their higher efficiency in spreading these viruses. The results of this study will be helpful for risk studies that need to quantify the deposition of virus in the environment.
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Guo Z, Huang J, Shi G, Su CH, Niu JJ. A food-borne outbreak of gastroenteritis caused by norovirus GII in a university located in Xiamen City, China. Int J Infect Dis 2014; 28:101-6. [PMID: 25263502 DOI: 10.1016/j.ijid.2014.06.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 06/30/2014] [Accepted: 06/30/2014] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVES We investigated a diarrhea outbreak that occurred at a university in China to identify the etiological agent of the outbreak, source of infection, mode of transmission, and risk factors. METHODS In this case-control study, we compared the food sources and examined the food and water items consumed between the probable and confirmed cases and the asymptomatic control students, who were selected randomly and frequency-matched by class and age at a ratio of 1:2. RESULTS Out of 7141 students (excluding teachers), 87 (1.2%) developed an illness. Thirty-three of 44 (75%) cases and 11 of 88 (13%) control students had consumed bread products supplied by an unlicensed small bakery (odds ratio 21, 95% confidence interval 8-60). Norovirus GII was detected in seven patients and in a food handler at the bread workshop and his 8-month-old son. CONCLUSIONS The outbreak of gastroenteritis was caused mainly by bread products contaminated with norovirus GII. A food handler with an asymptomatic norovirus GII infection was the possible source of infection.
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Affiliation(s)
- Zhinan Guo
- Xiamen Center for Disease Control and Prevention, Fujian, People's Republic of China
| | - Jianwei Huang
- Xiamen Center for Disease Control and Prevention, Fujian, People's Republic of China
| | - Guoqing Shi
- Chinese Field Epidemiology Training Program, Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Cheng-hao Su
- Xiamen Center for Disease Control and Prevention, Fujian, People's Republic of China
| | - Jian Jun Niu
- Zhongshan Hospital, Xiamen University, Xiamen, Fujian, People's Republic of China.
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23
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Cunliffe NA, Glass RI, Nakagomi O. Rotavirus and Other Viral Diarrhoea. MANSON'S TROPICAL INFECTIOUS DISEASES 2014. [PMCID: PMC7149922 DOI: 10.1016/b978-0-7020-5101-2.00019-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Lee RM, Lessler J, Lee RA, Rudolph KE, Reich NG, Perl TM, Cummings DAT. Incubation periods of viral gastroenteritis: a systematic review. BMC Infect Dis 2013; 13:446. [PMID: 24066865 PMCID: PMC3849296 DOI: 10.1186/1471-2334-13-446] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 09/12/2013] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Accurate knowledge of incubation period is important to investigate and to control infectious diseases and their transmission, however statements of incubation period in the literature are often uncited, inconsistent, and/or not evidence based. METHODS In a systematic review of the literature on five enteric viruses of public health importance, we found 256 articles with incubation period estimates, including 33 with data for pooled analysis. RESULTS We fit a log-normal distribution to pooled data and found the median incubation period to be 4.5 days (95% CI 3.9-5.2 days) for astrovirus, 1.2 days (95% CI 1.1-1.2 days) for norovirus genogroups I and II, 1.7 days (95% CI 1.5-1.8 days) for sapovirus, and 2.0 days (95% CI 1.4-2.4 days) for rotavirus. CONCLUSIONS Our estimates combine published data and provide sufficient quantitative detail to allow for these estimates to be used in a wide range of clinical and modeling applications. This can translate into improved prevention and control efforts in settings with transmission or the risk of transmission.
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Affiliation(s)
- Rachel M Lee
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Justin Lessler
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Rose A Lee
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Kara E Rudolph
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Nicholas G Reich
- Division of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusettes Amherst, Amherst, USA
| | - Trish M Perl
- Department of Medicine, Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Derek AT Cummings
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
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25
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Dicaprio E, Ma Y, Hughes J, Li J. Epidemiology, prevention, and control of the number one foodborne illness: human norovirus. Infect Dis Clin North Am 2013; 27:651-74. [PMID: 24011835 PMCID: PMC7126578 DOI: 10.1016/j.idc.2013.05.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Erin Dicaprio
- Department of Food Science and Technology, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, 110 Parker Food Science and Technology Building, 2015 Fyffe Road, Columbus, OH 43210, USA
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Mesquita JR, Costantini VP, Cannon JL, Lin SC, Nascimento MSJ, Vinjé J. Presence of antibodies against genogroup VI norovirus in humans. Virol J 2013; 10:176. [PMID: 23735311 PMCID: PMC3680240 DOI: 10.1186/1743-422x-10-176] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 05/31/2013] [Indexed: 02/06/2023] Open
Abstract
Background Noroviruses are important enteric pathogens in humans and animals. Recently, we reported a novel canine norovirus (CaNoV) in dogs with diarrhea belonging to a new genogroup (GVI). No data are available on exposure of humans to this virus. Methods Sera from 373 small animal veterinarians and 120 age-matched population controls were tested for IgG antibodies to CaNoV by a recombinant virus like particle based enzyme-linked immunosorbent assay. Results Antibodies to CaNoV were found in 22.3% of the veterinarians and 5.8% of the control group (p < 0.001). Mean corrected OD450 values for CaNoV antibodies were significantly higher in small animal veterinarians compared to the control group. Conclusions These findings suggest that CaNoV may infect humans and small animal veterinarians are at an increased risk for exposure to this virus. Additional studies are needed to assess if this virus is able to cause disease in humans.
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Affiliation(s)
- João Rodrigo Mesquita
- Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Porto, Portugal
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Li Y, Guo H, Xu Z, Zhou X, Zhang H, Zhang L, Miao J, Pan Y. An outbreak of norovirus gastroenteritis associated with a secondary water supply system in a factory in south China. BMC Public Health 2013; 13:283. [PMID: 23537289 PMCID: PMC3679847 DOI: 10.1186/1471-2458-13-283] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Accepted: 03/15/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Between September 17 and October 3, 2009, hundreds of workers employed in a manufacturing factory in Shenzhen, a city in south China developed a sudden onset of acute gastroenteritis. A retrospective cohort study is designed to identify the risk factors and control this outbreak. METHODS Information on demographic characteristics, working place, the history of contact with a person having diarrhea and/or vomiting, drink water preference and frequency, eating in the company cafeteria or outside the company, hand-washing habits and eating habits is included. Furthermore, in order to find the contamination source, we investigated the environment around the underground reservoir and collected water samples from the junction between municipal supply water system and underground reservoir to test potential bacteria and virus, examine the seepage tracks on the wall of the underground reservoir from the side of septic tank, and check the integrity and attitude of this lid. Relative risk was presented and Chi-square test was performed. All the analyses were performed with OpenEpi software version 2.3.1 online. RESULTS The cohort study demonstrated that the workers who had direct drink water were 3.0 fold more likely to suffer from acute gastroenteritis than those who consumed commercial bottled water. The direct drinking water, water of the tank of buildings, and the underground reservoir were positive only for norovirus. Norovirus was also detected from stool and rectal swab samples from patients with acute gastroenteritis. The underground reservoir was found to be the primary contamination source. Further environmental investigation showed that the norovirus contaminated substance entered into the underground reservoir via access holes in lid covering this underground reservoir. CONCLUSION This acute gastroenteritis outbreak was caused by the secondary supply system contaminated by norovirus in this factory. The outbreak of gastroenteritis cases caused by norovirus frequently occurred in China due to a lack of surveillance and supervision, and due to faults in the construction of such water systems. Therefore, more attentions should pay to the secondary supply water system in China.
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Affiliation(s)
- Yuan Li
- Department of infectious disease prevention and control, Shenzhen bao’an center for disease control and prevention, 116 Longjinger Road, Shenzhen 51810, China
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Multiple outbreaks of a novel norovirus GII.4 linked to an infected post-symptomatic food handler. Epidemiol Infect 2013; 141:1585-97. [DOI: 10.1017/s0950268813000095] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
SUMMARYMultiple norovirus outbreaks following catered events in Auckland, New Zealand, in September 2010 were linked to the same catering company and investigated. Retrospective cohort studies were undertaken with attendees of two events: 38 (24·1%) of 158 surveyed attendees developed norovirus-compatible illness. Attendees were at increased risk of illness if they had consumed food that had received manual preparation following cooking or that had been prepared within 45 h following end of symptoms in a food handler with prior gastroenteritis. All food handlers were tested for norovirus. A recombinant norovirus GII.e/GII.4 was detected in specimens from event attendees and the convalescent food handler. All catering company staff were tested; no asymptomatic norovirus carriers were detected. This investigation improved the characterization of norovirus risk from post-symptomatic food handlers by narrowing the potential source of transmission to one individual. Food handlers with gastroenteritis should be excluded from the workplace for 45 h following resolution of symptoms.
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Abstract
We report two genome sequences of novel noroviruses isolated from fecal swab specimens of brown rats in Hong Kong. The complete genome is approximately 7.5 kb in length and consists of 3 overlapping open reading frames encoding ORF1 polyprotein, VP1, and VP2, respectively. Sequence analysis suggested that these noroviruses should be classified in genogroup V, but they are distinct from other known rodent noroviruses and represent a novel cluster within the genogroup.
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Mathijs E, Stals A, Baert L, Botteldoorn N, Denayer S, Mauroy A, Scipioni A, Daube G, Dierick K, Herman L, Van Coillie E, Uyttendaele M, Thiry E. A review of known and hypothetical transmission routes for noroviruses. FOOD AND ENVIRONMENTAL VIROLOGY 2012; 4:131-52. [PMID: 23412887 DOI: 10.1007/s12560-012-9091-z] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 10/06/2012] [Indexed: 05/04/2023]
Abstract
Human noroviruses (NoVs) are considered a worldwide leading cause of acute non-bacterial gastroenteritis. Due to a combination of prolonged shedding of high virus levels in feces, virus particle shedding during asymptomatic infections, and a high environmental persistence, NoVs are easily transmitted pathogens. Norovirus (NoV) outbreaks have often been reported and tend to affect a lot of people. NoV is spread via feces and vomit, but this NoV spread can occur through several transmission routes. While person-to-person transmission is without a doubt the dominant transmission route, human infective NoV outbreaks are often initiated by contaminated food or water. Zoonotic transmission of NoV has been investigated, but has thus far not been demonstrated. The presented review aims to give an overview of these NoV transmission routes. Regarding NoV person-to-person transmission, the NoV GII.4 genotype is discussed in the current review as it has been very successful for several decades but reasons for its success have only recently been suggested. Both pre-harvest and post-harvest contamination of food products can lead to NoV food borne illness. Pre-harvest contamination of food products mainly occurs via contact with polluted irrigation water in case of fresh produce or with contaminated harvesting water in case of bivalve molluscan shellfish. On the other hand, an infected food handler is considered as a major cause of post-harvest contamination of food products. Both transmission routes are reviewed by a summary of described NoV food borne outbreaks between 2000 and 2010. A third NoV transmission route occurs via water and the spread of NoV via river water, ground water, and surface water is reviewed. Finally, although zoonotic transmission remains hypothetical, a summary on the bovine and porcine NoV presence observed in animals is given and the presence of human infective NoV in animals is discussed.
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Affiliation(s)
- Elisabeth Mathijs
- Department of Infectious and Parasitic diseases, Virology and Viral diseases, Faculty of Veterinary Medicine, University of Liège, Boulevard du Colonster 20, 4000, Liège, Belgium
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Abstract
We report the complete genome sequences of two novel isolates of norovirus isolated from the fecal swab specimens of dogs in Hong Kong. The complete viral genome is approximately 7.6 kb in length and consists of 3 overlapping open reading frames encoding the ORF1 polyprotein, VP1, and VP2, respectively. Analysis of the VP1 sequence suggested that these noroviruses are divergent from known noroviruses and may represent a novel phylogenetic clade within the genus.
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Li J, Predmore A, Divers E, Lou F. New Interventions Against Human Norovirus: Progress, Opportunities, and Challenges. Annu Rev Food Sci Technol 2012; 3:331-52. [DOI: 10.1146/annurev-food-022811-101234] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jianrong Li
- Department of Food Science and Technology, College of Food, Agricultural and Environmental Sciences, The Ohio State University, Columbus, Ohio 43210
- Division of Environmental Health Sciences, College of Public Health, The Ohio State University, Columbus, Ohio 43210;
| | - Ashley Predmore
- Department of Food Science and Technology, College of Food, Agricultural and Environmental Sciences, The Ohio State University, Columbus, Ohio 43210
| | - Erin Divers
- Department of Food Science and Technology, College of Food, Agricultural and Environmental Sciences, The Ohio State University, Columbus, Ohio 43210
| | - Fangfei Lou
- Department of Food Science and Technology, College of Food, Agricultural and Environmental Sciences, The Ohio State University, Columbus, Ohio 43210
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Kovač K, Diez-Valcarce M, Raspor P, Hernández M, Rodríguez-Lázaro D. Effect of high hydrostatic pressure processing on norovirus infectivity and genome stability in strawberry puree and mineral water. Int J Food Microbiol 2012; 152:35-9. [DOI: 10.1016/j.ijfoodmicro.2011.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 10/04/2011] [Accepted: 10/08/2011] [Indexed: 10/16/2022]
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34
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Desai R, Yen C, Wikswo M, Gregoricus NA, Provo JE, Parashar UD, Hall AJ. Transmission of norovirus among NBA players and staff, winter 2010-2011. Clin Infect Dis 2011; 53:1115-7. [PMID: 22042874 DOI: 10.1093/cid/cir682] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In December 2010, 24 players and staff members from 13 National Basketball Association teams were affected with gastroenteritis symptoms. Four of 5 stool specimens from ill players and staff tested positive for norovirus genogroup II. We document evidence of transmission both within teams and, potentially, between teams in 2 instances.
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Affiliation(s)
- Rishi Desai
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
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35
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Mahar JE, Kirkwood CD. Characterization of norovirus strains in Australian children from 2006 to 2008: Prevalence of recombinant strains. J Med Virol 2011; 83:2213-9. [DOI: 10.1002/jmv.22215] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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MacCannell T, Umscheid CA, Agarwal RK, Lee I, Kuntz G, Stevenson KB. Guideline for the prevention and control of norovirus gastroenteritis outbreaks in healthcare settings. Infect Control Hosp Epidemiol 2011; 32:939-69. [PMID: 21931246 DOI: 10.1086/662025] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Taranisia MacCannell
- Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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de Laval F, Nivoix P, Pommier de Santi V, Caballe D, Garnotel E, Maslin J. Severe Norovirus Outbreak Among Soldiers in the Field: Foodborne Followed by Person-to-Person Transmission. Clin Infect Dis 2011; 53:399-400. [DOI: 10.1093/cid/cir380] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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38
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Norovirus outbreak associated with undercooked oysters and secondary household transmission. Epidemiol Infect 2011; 140:276-82. [PMID: 21524343 DOI: 10.1017/s0950268811000665] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
During December 2009, over 200 individuals reported gastrointestinal symptoms after dining at a North Carolina restaurant. An outbreak investigation included a case-control study of restaurant patrons, a secondary household transmission study, environmental assessment of the restaurant facilities and operations, and laboratory analysis of stool and food samples. Illness was primarily associated with consumption of steamed oysters (odds ratio 12, 95% confidence interval 4·8-28) and 20% (8/41 households) reported secondary cases, with a secondary attack rate of 14% among the 70 susceptible household contacts. Norovirus RNA was detected in 3/5 stool specimens from ill patrons; sequencing of RT-PCR products from two of these specimens identified identical genogroup II genotype 12 sequences. Final cooked temperatures of the steamed oysters were generally inadequate to inactivate norovirus, ranging from 21°C to 74°C. Undercooked contaminated oysters pose a similar risk for norovirus illness as raw oysters and household contacts are at risk for secondary infection.
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Abstract
Public health planning in advance of the 2010 Olympic and Paralympic Winter Games included an assessment of potential public health risks for athletes attending the Games and mitigation activities to reduce those risks, including provision of vaccination recommendations to athletes. Physicians providing care to athletes who will attend large sporting events at home or abroad should consider their need for routine and additional vaccinations well in advance of the event to permit completion of vaccination schedules, ensure development of immunity, and avoid adverse vaccine reactions in the final stages of athlete training. Specific vaccinations recommended will vary depending on the location of the event and time of year it is scheduled. Other simple prevention measures for athletes include hand washing recommendations, avoiding high-risk foods, practicing safe sex, and taking simple precautions to reduce the risk of injuries. No major public health problems occurred during the 2010 Winter Games, but a measles outbreak began in Vancouver coincident in time with the Games; no known cases occurred among participating athletes.
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40
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Kovač K, Diez-Valcarce M, Hernandez M, Raspor P, Rodríguez-Lázaro D. High hydrostatic pressure as emergent technology for the elimination of foodborne viruses. Trends Food Sci Technol 2010. [DOI: 10.1016/j.tifs.2010.08.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Recent epidemiologic studies have shown that norovirus is one of the most frequent causes of acute nonbacterial gastroenteritis. Reverse-transcription polymerase chain reaction and nucleotide sequencing are the means by which the hundreds of norovirus strains have been identified, named, and classified into genogroups and genetic clusters. They are also the means by which a particular strain is traced from the source of an outbreak throughout its spread. These molecular techniques have been combined with classic epidemiology to investigate norovirus outbreaks in diverse settings, including hospitals, nursing homes, dining locations, schools, daycare centers, and vacation venues. Outbreaks are difficult to control because of the apparent ease of transmission through food, water, person-to-person contact, and environmental surfaces. Almost all patients with norovirus gastroenteritis recover completely, but hospital and nursing home outbreaks have been associated with morbidity and mortality. The diagnostic and management approach to an individual patient is to use clinical and epidemiologic findings to rule out "not norovirus." At the first sign that there is an outbreak, strict compliance with cleaning, disinfection, and work release guidelines is important to prevent further spread.
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Affiliation(s)
- Richard Goodgame
- Baylor College of Medicine, 1 Baylor Plaza, Room 525-D, Houston, TX 77030, USA.
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Wadl M, Scherer K, Nielsen S, Diedrich S, Ellerbroek L, Frank C, Gatzer R, Hoehne M, Johne R, Klein G, Koch J, Schulenburg J, Thielbein U, Stark K, Bernard H. Food-borne norovirus-outbreak at a military base, Germany, 2009. BMC Infect Dis 2010; 10:30. [PMID: 20163705 PMCID: PMC2831023 DOI: 10.1186/1471-2334-10-30] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Accepted: 02/17/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Norovirus is often transmitted from person-to-person. Transmission may also be food-borne, but only few norovirus outbreak investigations have identified food items as likely vehicles of norovirus transmission through an analytical epidemiological study.During 7-9 January, 2009, 36 persons at a military base in Germany fell ill with acute gastroenteritis. Food from the military base's canteen was suspected as vehicle of infection, norovirus as the pathogen causing the illnesses. An investigation was initiated to describe the outbreak's extent, to verify the pathogen, and to identify modes of transmission and source of infection to prevent further cases. METHODS For descriptive analysis, ill persons were defined as members of the military base with acute onset of diarrhoea or vomiting between 24 December 2008, and 3 February 2009, without detection of a pathogen other than norovirus in stools. We conducted a retrospective cohort study within the headquarters company. Cases were military base members with onset of diarrhoea or vomiting during 5-9 January. We collected information on demographics, food items eaten at the canteen and contact to ill persons or vomit, using a self-administered questionnaire. We compared attack rates (AR) in exposed and unexposed persons, using bivariable and multivariable logistic regression modelling. Stool specimens of ill persons and canteen employees, canteen food served during 5-7 January and environmental swabs were investigated by laboratory analysis. RESULTS Overall, 101/815 (AR 12.4%) persons fell ill between 24 December 2008 and 3 February 2009. None were canteen employees. Most persons (n = 49) had disease onset during 7-9 January. Ill persons were a median of 22 years old, 92.9% were male. The response for the cohort study was 178/274 (72.1%). Of 27 cases (AR 15.2%), 25 had eaten at the canteen and 21 had consumed salad. Salad consumption on 6 January (aOR: 8.1; 95%CI: 1.5-45.4) and 7 January (aOR: 15.7; 95%CI: 2.2-74.1) were independently associated with increased risk of disease.Norovirus was detected in 8/28 ill persons' and 4/25 canteen employees' stools, 6/55 environmental swabs and 0/33 food items. Sequences were identical in environmental and stool samples (subtype II.4 2006b), except for those of canteen employees. Control measures comprised cohort isolation of symptomatic persons, exclusion of norovirus-positive canteen employees from work and disinfection of the canteen's kitchen. CONCLUSIONS Our investigation indicated that consumption of norovirus-contaminated salad caused the peak of the outbreak on 7-9 January. Strict personal hygiene and proper disinfection of environmental surfaces remain crucial to prevent norovirus transmission.
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Affiliation(s)
- Maria Wadl
- Postgraduate Training for Applied Epidemiology, Germany.
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Nishimura N, Nakayama H, Yoshizumi S, Miyoshi M, Tonoike H, Shirasaki Y, Kojima K, Ishida S. Detection of noroviruses in fecal specimens by direct RT-PCR without RNA purification. J Virol Methods 2010; 163:282-6. [DOI: 10.1016/j.jviromet.2009.10.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Revised: 10/14/2009] [Accepted: 10/19/2009] [Indexed: 12/29/2022]
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ter Waarbeek HLG, Dukers-Muijrers NHTM, Vennema H, Hoebe CJPA. Waterborne gastroenteritis outbreak at a scouting camp caused by two norovirus genogroups: GI and GII. J Clin Virol 2010; 47:268-72. [PMID: 20056481 DOI: 10.1016/j.jcv.2009.12.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2009] [Revised: 12/03/2009] [Accepted: 12/07/2009] [Indexed: 11/18/2022]
Abstract
BACKGROUND A cross-border gastroenteritis outbreak at a scouting camp was associated with drinking water from a farmer's well. OBJECTIVES A retrospective cohort study was performed to identify size and source of the outbreak, as well as other characteristics. STUDY DESIGN Epidemiological investigation included standardized questionnaires about sex, age, risk exposures, illness and family members. Stool and water (100mL) samples were analyzed for bacteria, viruses and parasites. RESULTS Questionnaires were returned by 84 scouts (response rate 82%), mean age of 13 years. The primary attack rate was 85% (diarrhoea and/or vomiting). Drinking water was the strongest independent risk factor showing a dose-response effect with 50%, 75%, 75%, 93% and 96% case prevalence for 0, 1, 2-3, 4-5 and >5 glasses consumed, respectively. Norovirus (GI.2 Southampton and GII.7 Leeds) was detected in 51 stool specimens (75%) from ill scouts. Water analysis showed fecal contamination, but no norovirus. The secondary attack rate was 20%. CONCLUSIONS This remarkable outbreak was caused by a point-source infection with two genogroups of noroviruses most likely transmitted by drinking water from a well. Finding a dose-response relationship was striking. Specific measures to reduce the risk of waterborne diseases, outbreak investigation and a good international public health network are important.
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Affiliation(s)
- Henriëtte L G ter Waarbeek
- Department of Infectious Diseases, Public Health Service South Limburg, 6160 HA Geleen, The Netherlands.
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Abstract
PURPOSE OF REVIEW Physical exercise can be both beneficial and harmful for the gastrointestinal tract in a dose-effect relationship between its intensity and health. Mild-to-moderate intensity exercises play a protective role against colon cancer, diverticular disease, cholelithiasis and constipation, whereas acute strenuous exercise may provoke heartburn, nausea, vomiting, abdominal pain, diarrhea and even gastrointestinal bleeding. This review focuses on mechanisms involved in those symptoms and their associations with type of exercises in humans. RECENT FINDINGS One quarter to one half of elite athletes are hampered by the gastrointestinal symptoms that may deter them from participation in training and competitive events. Vigorous exercise-induced gastrointestinal symptoms are often attributed to altered motility, mechanical factor or altered neuroimmunoendocrine secretions. Training, lifestyle modifications, meal composition, adequate hydration and avoidance of excessive use of some medications are the recommendations. SUMMARY Strenuous exercise and dehydrated states would be the causes of gastrointestinal symptoms referred by 70% of the athletes. Gut ischemia would be the main cause of nausea, vomiting, abdominal pain and (bloody) diarrhea. The frequency is almost twice as high during running than during other endurance sports as cycling or swimming and 1.5-3.0 times higher in the elite athletes than the recreational exercisers.
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Affiliation(s)
- Erick Prado de Oliveira
- Centre for Physical Exercise and Nutrition Metabolism, UNESP School of Medicine, Public Health Department, Botucatu City, São Paulo State, Brazil
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Armbrust S, Kramer A, Olbertz D, Zimmermann K, Fusch C. Norovirus infections in preterm infants: wide variety of clinical courses. BMC Res Notes 2009; 2:96. [PMID: 19490612 PMCID: PMC2695820 DOI: 10.1186/1756-0500-2-96] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Accepted: 06/02/2009] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Norovirus is an important cause of nonbacterial acute gastroenteritis in all ages. Atypical courses are described. Clinical symptoms are diarrhea, vomiting, nausea, abdominal cramps, fever and malaise. Apart from three recent short reports we describe for the first time an outbreak of norovirus in a tertiary Neonatal Intensive Care Unit. FINDINGS The typical symptoms of norovirus infection are in part also seen in premature born infants but with a different pattern and a huge variety of clinical courses. Vomiting is not the main symptom of norovirus infection in premature infants but distended abdomen and other symptoms such as apnea, gastric remainders or sepsis like appearance. The course in premature born patients could be explained by an immunocompromised mice model. Extensive hygienic measures were necessary to control the outbreak without closing the Neonatal Intensive Care Unit. CONCLUSION Norovirus infection in premature infants shows an impressive pattern of a wide variety of clinical courses. Only the consequent use of different hygienic pattern can lead to elimination of norovirus.
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Affiliation(s)
- Sven Armbrust
- Department of Neonatology, University-Children's Hospital, 17475 Greifswald, Germany
| | - Axel Kramer
- Institute for Hygiene and Environmental Medicine, Ernst Moritz Arndt University Greifswald, 17475 Greifswald, Germany
| | - Dirk Olbertz
- Department of Neonatology, Suedstadt Clinic, 18059 Rostock, Germany
| | - Kathrin Zimmermann
- Friedrich Loeffler Institute for Medical Microbiology, Ernst Moritz Arndt University Greifswald, 17475 Greifswald, Germany
| | - Christoph Fusch
- Department of Neonatology, University-Children's Hospital, 17475 Greifswald, Germany
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Todd ECD, Greig JD, Bartleson CA, Michaels BS. Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 6. Transmission and survival of pathogens in the food processing and preparation environment. J Food Prot 2009; 72:202-19. [PMID: 19205488 DOI: 10.4315/0362-028x-72.1.202] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This article, the sixth in a series reviewing the role of food workers in foodborne outbreaks, describes the source and means of pathogen transfer. The transmission and survival of enteric pathogens in the food processing and preparation environment through human and raw food sources is reviewed, with the main objective of providing information critical to the reduction of illness due to foodborne outbreaks. Pathogens in the food preparation area can originate from infected food workers, raw foods, or other environmental sources. These pathogens can then spread within food preparation or processing facilities through sometimes complex pathways and may infect one or more workers or the consumer of foods processed or prepared by these infected workers. The most frequent means of worker contamination is the fecal-oral route, and study results have indicated that toilet paper may not stop transmission of pathogens to hands. However, contact with raw foods of animal origin, worker aerosols (from sneezes), vomitus, and exposed hand lesions also have been associated with outbreaks. Transfer of pathogens has been documented through contaminated fabrics and carpets, rings, currency, skin surfaces, dust, and aerosols and though person-to-person transmission. Results of experiments on pathogen survival have indicated that transmission depends on the species, the inoculum delivery route, the contact surface type, the duration and temperature of exposure, and the relative humidity. Generally, viruses and encysted parasites are more resistant than enteric bacteria to adverse environmental conditions, but all pathogens can survive long enough for transfer from a contaminated worker to food, food contact surfaces, or fellow workers.
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Affiliation(s)
- Ewen C D Todd
- Food Safety Policy Center, Michigan State University, East Lansing, Michigan 48824, USA.
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Noroviruses: a comprehensive review. J Clin Virol 2008; 44:1-8. [PMID: 19084472 DOI: 10.1016/j.jcv.2008.10.009] [Citation(s) in RCA: 524] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 10/10/2008] [Accepted: 10/14/2008] [Indexed: 02/08/2023]
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