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Strakova N, Michova H, Shagieva E, Ovesna P, Karpiskova R, Demnerova K. Genotyping of Campylobacter jejuni and prediction tools of its antimicrobial resistance. Folia Microbiol (Praha) 2024; 69:207-219. [PMID: 37816942 PMCID: PMC10876727 DOI: 10.1007/s12223-023-01093-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 09/09/2023] [Indexed: 10/12/2023]
Abstract
Although Campylobacter jejuni is the pathogen responsible for the most common foodborne illness, tracing of the infection source remains challenging due to its highly variable genome. Therefore, one of the aim of the study was to compare three genotyping methods (MLST, PFGE, and mP-BIT) to determine the most effective genotyping tool. C. jejuni strains were divided into 4 clusters based on strain similarity in the cgMLST dendrogram. Subsequently, the dendrograms of the 3 tested methods were compared to determine the accuracy of each method compared to the reference cgMLST method. Moreover, a cost-benefit analysis has showed that MLST had the highest inverse discrimination index (97%) and required less workflow, time, fewer consumables, and low bacterial sample quantity. PFGE was shown to be obsolete both because of its low discriminatory power and the complexity of the procedure. Similarly, mP‑BIT showed low separation results, which was compensated by its high availability. Therefore, our data showed that MLST is the optimal tool for genotyping C. jejuni. Another aim was to compare the antimicrobial resistance to ciprofloxacin, erythromycin, and tetracycline in C. jejuni strains isolated from human, water, air, food, and animal samples by two gene sequence-based prediction methods and to compare them with the actual susceptibility of C. jejuni strains using the disc diffusion method. Both tools, ResFinder and RGI, synchronously predict the antimicrobial susceptibility of C. jejuni and either can be used.
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Affiliation(s)
- Nicol Strakova
- Veterinary Research Institute, Hudcova 296/70, Brno, Czech Republic.
| | - Hana Michova
- Laboratory of Food Microbiology, Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Czech Republic
| | - Ekaterina Shagieva
- Laboratory of Food Microbiology, Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Czech Republic
| | - Petra Ovesna
- Institute of Biostatistics and Analyses, Masaryk University, Brno, Czech Republic
| | - Renata Karpiskova
- Department of Public Health, Medical Faculty, Masaryk University, Brno, Czech Republic
| | - Katerina Demnerova
- Laboratory of Food Microbiology, Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Czech Republic
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Gitter A, Mena KD, Lisle JT. Informing ASR Treatment Practices in a Florida Aquifer through a Human Health Risk Approach. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6833. [PMID: 37835103 PMCID: PMC10572346 DOI: 10.3390/ijerph20196833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/05/2023] [Accepted: 09/21/2023] [Indexed: 10/15/2023]
Abstract
Aquifer storage and recovery (ASR) can augment water supplies and hydrologic flows under varying climatic conditions. However, imposing drinking water regulations on ASR practices, including pre-treatment before injection into the aquifer, remains arguable. Microbial inactivation data-Escherichia coli, Pseudomonas aeruginosa, poliovirus type 1 and Cryptosporidium parvum-were used in a human health risk assessment to identify how the storage time of recharged water in the Floridan Aquifer enhances pathogen inactivation, thereby mitigating the human health risks associated with ingestion. We used a quantitative microbial risk assessment to evaluate the risks for a gastrointestinal infection (GI) and the associated disability-adjusted life years (DALYs) per person per year. The risk of developing a GI infection for drinking water no longer exceeded the suggested annual risk threshold (1 × 10-4) by days 31, 1, 52 and 80 for each pathogen, respectively. DALYs per person per year no longer exceeded the World Health Organization threshold (1 × 10-6) by days 27, <1, 43 and 72. In summary, storage time in the aquifer yields a significant reduction in health risk. The findings emphasize that considering microbial inactivation, caused by storage time and geochemical conditions within ASR storage zones, is critical for recharge water treatment processes.
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Affiliation(s)
- Anna Gitter
- Department of Epidemiology, Human Genetics and Environmental Sciences, University of Texas Health Science Center-Houston School of Public Health, Houston, TX 77030, USA;
| | - Kristina D. Mena
- Department of Epidemiology, Human Genetics and Environmental Sciences, University of Texas Health Science Center-Houston School of Public Health, Houston, TX 77030, USA;
| | - John T. Lisle
- U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL 33701, USA;
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Bhatt A, Dada AC, Prajapati SK, Arora P. Integrating life cycle assessment with quantitative microbial risk assessment for a holistic evaluation of sewage treatment plant. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160842. [PMID: 36509266 DOI: 10.1016/j.scitotenv.2022.160842] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 11/12/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
An integrated approach was employed in the present study to combine life cycle assessment (LCA) with quantitative microbial risk assessment (QMRA) to assess an existing sewage treatment plant (STP) at Roorkee, India. The midpoint LCA modeling revealed that high electricity consumption (≈ 576 kWh.day-1) contributed to the maximum environmental burdens. The LCA endpoint result of 0.01 disability-adjusted life years per person per year (DALYs pppy) was obtained in terms of the impacts on human health. Further, a QMRA model was developed based on representative sewage pathogens, including E. coli O157:H7, Giardia sp., adenovirus, norovirus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The public health risk associated with intake of pathogen-laden aerosols during treated water reuse in sprinkler irrigation was determined. A cumulative health risk of 0.07 DALYs pppy was obtained, where QMRA risks contributed 86 % of the total health impacts. The annual probability of illness per person was highest for adenovirus and norovirus, followed by SARS-CoV-2, E. coli O157:H7 and Giardia sp. Overall, the study provides a methodological framework for an integrated LCA-QMRA assessment which can be applied across any treatment process to identify the hotspots contributing maximum environmental burdens and microbial health risks. Furthermore, the integrated LCA-QMRA approach could support stakeholders in the water industry to select the most suitable wastewater treatment system and establish regulations regarding the safe reuse of treated water.
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Affiliation(s)
- Ankita Bhatt
- Department of Hydro and Renewable Energy, Indian Institute of Technology Roorkee, Uttarakhand, India
| | | | - Sanjeev Kumar Prajapati
- Department of Hydro and Renewable Energy, Indian Institute of Technology Roorkee, Uttarakhand, India
| | - Pratham Arora
- Department of Hydro and Renewable Energy, Indian Institute of Technology Roorkee, Uttarakhand, India.
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Epidemiology of Norovirus in the First 2 Years of Life in an Australian Community-based Birth Cohort. Pediatr Infect Dis J 2022; 41:878-884. [PMID: 36223234 DOI: 10.1097/inf.0000000000003667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Noroviruses are a leading cause of acute gastroenteritis across all age groups in Australia. We explored the epidemiology of symptomatic and asymptomatic norovirus infection and assessed risk factors and the related healthcare burden in Australian children during their first 2 years of life. METHODS Participants in the Observational Research in Childhood Infectious Diseases birth cohort provided weekly stool swabs, daily gastrointestinal symptoms (vomiting and loose stools) observations and healthcare data. Swabs were batch-tested for norovirus genogroups (GI and GII) using real-time polymerase chain reaction assays. RESULTS Overall, 158 children returned 11,124 swabs. There were 221 infection episodes, of which 183 (82.8%) were GII. The incidence rate was 0.90 infections per child-year [95% confidence interval (CI): 0.74-1.09]. The symptomatic infection incidence rate was 0.39 per child-year (95% CI: 0.31-0.48), peaking between ages 6 and 11 months [0.58 (95% CI: 0.41-0.81)]. Incidence increased significantly with age and childcare attendance. Of 209 episodes with symptom diary data, 82 (39.2%) were symptomatic; of these 70 (85.4%) were associated with vomiting and 29 (35.4%) with diarrhea. Forty-one percent of symptomatic episodes required healthcare, including 4 emergency department presentations and 1 hospitalization. Children with initial infections had almost twice the risk of seeking primary healthcare compared to subsequent infections (adjusted risk ratio 1.92; 95% CI: 1.01-3.65). CONCLUSIONS Norovirus infections, particularly GII, are common in Australian children 6-23 months of age. Estimates of norovirus incidence, including symptomatic infections and healthcare utilization in community settings in young children, are crucial for planning norovirus vaccine programs and determining vaccine effectiveness.
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Deere D, Ryan U. Current assumptions for quantitative microbial risk assessment (QMRA) of Norovirus contamination of drinking water catchments due to recreational activities: an update. JOURNAL OF WATER AND HEALTH 2022; 20:1543-1557. [PMID: 36308498 DOI: 10.2166/wh.2022.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Contamination of drinking water from Norovirus (NoV) and other waterborne viruses is a major public health concern globally. Increasingly, quantitative microbial risk assessment (QMRA) is being used to assess the various risks from waterborne pathogens and evaluate control strategies. As urban populations grow and expand, there is increasing demand for recreational activities in drinking water catchments. QMRA relies on context-specific data to map out the pathways by which viruses can enter water and be transferred to drinking water consumers and identify risk factors and appropriate controls. This review examines the current evidence base and assumptions for QMRA analysis of NoV and other waterborne viral pathogens and recommends numerical values based on the most recent evidence to better understand the health risks associated with recreators in Australian drinking water sources; these are broadly applicable to all drinking water sources where recreational access is allowed. Key issues include the lack of an agreed upon data and dose-response models for human infectious NoV genotypes, faecal shedding by bathers, the extent of NoV infectivity and aggregation, resistance (secretor status) to NoV and the extent of secondary transmission.
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Affiliation(s)
- Dan Deere
- Water Futures and Water Research Australia, Sydney, Australia
| | - Una Ryan
- Harry Butler Institute, Murdoch University, Perth, Australia E-mail:
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Ryan U, Hill K, Deere D. Review of generic screening level assumptions for quantitative microbial risk assessment (QMRA) for estimating public health risks from Australian drinking water sources contaminated with Cryptosporidium by recreational activities. WATER RESEARCH 2022; 220:118659. [PMID: 35635918 DOI: 10.1016/j.watres.2022.118659] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 04/26/2022] [Accepted: 05/21/2022] [Indexed: 06/15/2023]
Abstract
As urban communities continue to grow, demand for recreational access (including swimming) in drinking water sources have increased, yet relatively little is understood about the public health implications this poses for drinking water consumers. Preventative risk-based approaches to catchment management, informed by quantitative microbial risk assessment (QMRA), requires accurate input data to effectively model risks. A sound understanding of the knowledge gaps is also important to comprehend levels of uncertainty and help prioritise research needs. Cryptosporidium is one of the most important causes of waterborne outbreaks of gastroenteritis globally due to its resistance to chlorine. This review was undertaken by Water Research Australia to provide the most up-to-date information on current Cryptosporidium epidemiological data and underlying assumptions for exposure assessment, dose response and risk assessment for generic components of QMRA for Cryptosporidium and highlights priorities for common research. Key interim recommendations and guidelines for numerical values for relatively simple screening level QMRA modelling are provided to help support prospective studies of risks to drinking water consumers from Cryptosporidium due to body-contact recreation in source water. The review does not cover site-specific considerations, such as the levels of activity in the source water, the influence of dilution and inactivation in reservoirs, or water treatment. Although the focus is Australia, the recommendations and numerical values developed in this review, and the highlighted research priorities, are broadly applicable across all drinking source water sources that allow recreational activities.
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Affiliation(s)
- U Ryan
- Harry Butler Institute, Murdoch University, 90 South Street, Perth, Australia.
| | - Kelly Hill
- Water Research Australia, 250 Victoria Square, Adelaide, South Australia, Australia
| | - Dan Deere
- Water Futures, Sydney, Australia and Water Research Australia, Australia
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Haldar K, Kujawa-Roeleveld K, Hofstra N, Datta DK, Rijnaarts H. Microbial contamination in surface water and potential health risks for peri-urban farmers of the Bengal delta. Int J Hyg Environ Health 2022; 244:114002. [PMID: 35759864 DOI: 10.1016/j.ijheh.2022.114002] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 06/08/2022] [Accepted: 06/11/2022] [Indexed: 11/18/2022]
Abstract
Ensuring safe irrigation practices is vital to sustaining food production in water-scarce delta areas. Bangladesh and many other developing countries discharge untreated wastewater into their surrounding surface water bodies, serving as the primary irrigation source. This indirect irrigation of wastewater is believed to pose threats to the farmers, consumers and market vendors and may also affect crop and soil quality. To assess the risk, peri-urban farmers who use surrounding water bodies of Khulna city, Bangladesh, for crop irrigation were selected for the study. The microbial and heavy metal concentrations were measured in water samples collected from various locations over different seasons. For heavy metals As, Co, Ni, Cd, Cr, Cu and Pb, concentrations were below the detection limit, whereas Al, Fe, Mn, Ti and Zn were present but below the FAO recommendation limit for safe irrigation. The mean concentrations of microbial parameters were above the thresholds of WHO guidelines for crop irrigation intended for human consumption. Significant temporal variations in Faecal Coliform, E. coli and Enterococcus concentrations in the water samples were observed. The annual risk of infection for farmers was determined using the screening-level Quantitative Microbial Risk Assessment (QMRA). The results indicated that the annual probability of infection with pathogenic E. coli in different seasons ranges between 5 × 10-3 to 5 × 10-2, above the WHO's acceptable threshold for annual risk of infection for safe water reuse in agriculture. During the farmers' survey, around 45% reported health-related issues and more than 26% reported suffering from water-borne diseases after getting in contact with polluted surface water. This illustrates the actuality of the risks in practice. To ensure safe irrigation, the health risks need to be reduced below the acceptable limits. Suggested technical measures include adequate treatment of wastewater before disposal into rivers and access to protective equipment for farmers. This should be complemented by raising awareness through education programs among farmers to reduce accidental ingestion.
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Affiliation(s)
- Kamonashish Haldar
- Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700AA, Wageningen, the Netherlands.
| | - Katarzyna Kujawa-Roeleveld
- Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700AA, Wageningen, the Netherlands
| | - Nynke Hofstra
- Water Systems and Global Change, Wageningen University and Research, P.O. Box 47, 6700AA, Wageningen, the Netherlands
| | - Dilip Kumar Datta
- Environmental Science Discipline, Khulna University, Khulna, 9208, Bangladesh
| | - Huub Rijnaarts
- Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700AA, Wageningen, the Netherlands
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Sylvestre É, Dorner S, Burnet JB, Smeets P, Medema G, Cantin P, Villion M, Robert C, Ellis D, Servais P, Prévost M. Changes in Escherichia coli to enteric protozoa ratios in rivers: Implications for risk-based assessment of drinking water treatment requirements. WATER RESEARCH 2021; 205:117707. [PMID: 34619609 DOI: 10.1016/j.watres.2021.117707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/11/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Minimum treatment requirements are set in response to established or anticipated levels of enteric pathogens in the source water of drinking water treatment plants (DWTPs). For surface water, contamination can be determined directly by monitoring reference pathogens or indirectly by measuring fecal indicators such as Escherichia coli (E. coli). In the latter case, a quantitative interpretation of E. coli for estimating reference pathogen concentrations could be used to define treatment requirements. This study presents the statistical analysis of paired E. coli and reference protozoa (Cryptosporidium, Giardia) data collected monthly for two years in source water from 27 DWTPs supplied by rivers in Canada. E. coli/Cryptosporidium and E. coli/Giardia ratios in source water were modeled as the ratio of two correlated lognormal variables. To evaluate the potential of E. coli for defining protozoa treatment requirements, risk-based critical mean protozoa concentrations in source water were determined with a reverse quantitative microbial risk assessment (QMRA) model. Model assumptions were selected to be consistent with the World Health Organization (WHO) Guidelines for drinking-water quality. The sensitivity of mean E. coli concentration trigger levels to identify these critical concentrations in source water was then evaluated. Results showed no proportionalities between the log of mean E. coli concentrations and the log of mean protozoa concentrations. E. coli/protozoa ratios at DWTPs supplied by small rivers in agricultural and forested areas were typically 1.0 to 2.0-log lower than at DWTPs supplied by large rivers in urban areas. The seasonal variations analysis revealed that these differences were related to low mean E. coli concentrations during winter in small rivers. To achieve the WHO target of 10-6 disability-adjusted life year (DALY) per person per year, a minimum reduction of 4.0-log of Cryptosporidium would be required for 20 DWTPs, and a minimum reduction of 4.0-log of Giardia would be needed for all DWTPs. A mean E. coli trigger level of 50 CFU 100 mL-1 would be a sensitive threshold to identify critical mean concentrations for Cryptosporidium but not for Giardia. Treatment requirements higher than 3.0-log would be needed at DWTPs with mean E. coli concentrations as low as 30 CFU 100 mL-1 for Cryptosporidium and 3 CFU 100 mL-1 for Giardia. Therefore, an E. coli trigger level would have limited value for defining health-based treatment requirements for protozoa at DWTPs supplied by small rivers in rural areas.
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Affiliation(s)
- Émile Sylvestre
- NSERC Industrial Chair on Drinking Water, Department of Civil, Geological, and Mining Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada; Canada Research Chair in Source Water Protection, Department of Civil, Geological, and Mining Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada.
| | - Sarah Dorner
- Canada Research Chair in Source Water Protection, Department of Civil, Geological, and Mining Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada
| | - Jean-Baptiste Burnet
- NSERC Industrial Chair on Drinking Water, Department of Civil, Geological, and Mining Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada; Canada Research Chair in Source Water Protection, Department of Civil, Geological, and Mining Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada
| | - Patrick Smeets
- KWR Water Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, The Netherlands
| | - Gertjan Medema
- KWR Water Research Institute, Groningenhaven 7, 3433 PE Nieuwegein, The Netherlands; Sanitary Engineering, Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, P.O. Box 5048, 2600GA Delft, The Netherlands
| | - Philippe Cantin
- Ministère de l'Environnement et de la Lutte contre les changements climatiques, Québec, Canada
| | - Manuela Villion
- Centre d'expertise en analyse environnementale du Québec, Ministère de l'Environnement et de la Lutte contre les changements climatiques, Québec, Canada
| | - Caroline Robert
- Ministère de l'Environnement et de la Lutte contre les changements climatiques, Québec, Canada
| | - Donald Ellis
- Ministère de l'Environnement et de la Lutte contre les changements climatiques, Québec, Canada
| | - Pierre Servais
- Ecology of Aquatic Systems, Université libre de Bruxelles, Brussels, Belgium
| | - Michèle Prévost
- NSERC Industrial Chair on Drinking Water, Department of Civil, Geological, and Mining Engineering, Polytechnique Montreal, Montreal, Quebec H3C 3A7, Canada
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Petterson S, Bradford-Hartke Z, Leask S, Jarvis L, Wall K, Byleveld P. Application of QMRA to prioritise water supplies for Cryptosporidium risk in New South Wales, Australia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 784:147107. [PMID: 34088069 DOI: 10.1016/j.scitotenv.2021.147107] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/31/2021] [Accepted: 04/09/2021] [Indexed: 06/12/2023]
Abstract
A Quantitative Microbial Risk Assessment (QMRA) framework was applied to assess 312 drinking water supply systems across regional New South Wales (NSW). The framework was needed to support the implementation of a recommendation in the Australian Drinking Water Guidelines (ADWG) for appropriate treatment barriers to be operating in systems 'at risk' for Cryptosporidium. The objective was to prioritise systems so that those with the highest risk could be identified and addressed first. The framework was developed in a pilot study of 30 systems, selected to represent the range of water supplies across regional NSW. From these, source water categories were defined to represent local conditions with reference to the literature and Cryptosporidium risk factors. Values for Cryptosporidium oocyst concentration were assigned to the categories to allow quantification of the health risk from those water sources. The framework was then used to assess the risks in all 312 regional drinking water supply systems. Combining the disciplined approach of QMRA with simple catchment and treatment information and categorical risk outputs provided a useful and transparent method for prioritising systems for further investigation and potential risk management intervention. The risk rankings for drinking water supplies from this QMRA process have been used to set priorities for a large State Government funding program.
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Affiliation(s)
- S Petterson
- Water& Health Pty Ltd, North Sydney, Australia; School of Medicine, Griffith University, Australia.
| | - Z Bradford-Hartke
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - S Leask
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - L Jarvis
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - K Wall
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
| | - P Byleveld
- Water Unit, Environmental Health Branch, NSW Health, St Leonards, Australia
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He WQ, Kirk MD, Hall J, Liu B. Prescribing Antimicrobial Drugs for Acute Gastroenteritis, Primary Care, Australia, 2013-2018. Emerg Infect Dis 2021; 27. [PMID: 33900909 PMCID: PMC8084523 DOI: 10.3201/eid2705.203692] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Prescriptions for 6.8% of cases suggests a need for greater antimicrobial stewardship. During 2013–2018, antimicrobial drugs were prescribed for 6.8% of cases of acute gastroenteritis encountered in general practice in Australia, including 35.7% of Salmonella infections and 54.1% of Campylobacter infections. During that time, prescriptions for acute gastroenteritis decreased by 2.0%. Managing infectious gastroenteritis in general practice will require greater antimicrobial stewardship.
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Alexandridou M, Cattaert T, Verstraeten T. Estimation of Risk of Death Attributable to Acute Gastroenteritis Not Caused by Clostridioides difficile Infection Among Hospitalized Adults in England. Clin Epidemiol 2021; 13:309-315. [PMID: 33935520 PMCID: PMC8079255 DOI: 10.2147/clep.s296516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 03/18/2021] [Indexed: 11/23/2022] Open
Abstract
Introduction The role of an infectious agent may be unclear as the primary cause of death. Furthermore, many infections go undiagnosed, particularly if identification does not affect treatment. To circumvent the limitations of individual death attribution, a population-level assessment of the role of infectious acute gastroenteritis (AGE) was performed. Methods Using the Clinical Practice Research Datalink and the Office for National Statistics - Mortality Statistics, covering 16 million patients in the UK, we conducted a matched case-control study to estimate the odds of having AGE not due to Clostridioides difficile infection (CDI) diagnosed in the month before death among hospitalized adults in England. To estimate the number of deaths, we first estimated the attributable fraction (AF). The population attributable fraction (PAF) was then derived by multiplying AF with the proportion of AGE hospitalizations among all hospitalizations. Finally, by multiplying the PAF with the number of deaths, the number of deaths attributable to AGE not caused by CDI among hospitalized patients was estimated. Results The odds of having AGE not caused by CDI was 4.6 times higher among fatal compared to non-fatal hospitalizations. The overall PAF was 1.7% for AGE not caused by CDI. The overall number of deaths attributable to AGE not caused by CDI among adults in England is estimated to be 5000 annually. Discussion Approximately 5000 of the 276,000 deaths that occur annually among hospitalized adults in England can be attributed to AGE not caused by CDI, which is higher than previously estimated.
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Affiliation(s)
| | - Tom Cattaert
- P95 Pharmacovigilance and Epidemiology Services, Leuven, Belgium
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Byrne DM, Hamilton KA, Houser SA, Mubasira M, Katende D, Lohman HAC, Trimmer JT, Banadda N, Zerai A, Guest JS. Navigating Data Uncertainty and Modeling Assumptions in Quantitative Microbial Risk Assessment in an Informal Settlement in Kampala, Uganda. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:5463-5474. [PMID: 33750111 DOI: 10.1021/acs.est.0c05693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Decision-makers in developing communities often lack credible data to inform decisions related to water, sanitation, and hygiene. Quantitative microbial risk assessment (QMRA), which quantifies pathogen-related health risks across exposure routes, can be informative; however, the utility of QMRA for decision-making is often undermined by data gaps. This work integrates QMRA, uncertainty and sensitivity analyses, and household surveys in Bwaise, Kampala (Uganda) to characterize the implications of censored data management, identify sources of uncertainty, and incorporate risk perceptions to improve the suitability of QMRA for informal settlements or similar settings. In Bwaise, drinking water, hand rinse, and soil samples were collected from 45 households and supplemented with data from 844 surveys. Quantified pathogen (adenovirus, Campylobacter jejuni, and Shigella spp./EIEC) concentrations were used with QMRA to model infection risks from exposure through drinking water, hand-to-mouth contact, and soil ingestion. Health risks were most sensitive to pathogen data, hand-to-mouth contact frequency, and dose-response models (particularly C. jejuni). When managing censored data, results from upper limits of detection, half of limits of detection, and uniform distributions returned similar results, which deviated from lower limits of detection and maximum likelihood estimation imputation approaches. Finally, risk perceptions (e.g., it is unsafe to drink directly from a water source) were identified to inform risk management.
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Affiliation(s)
- Diana M Byrne
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Avenue, 3221 Newmark Civil Engineering Laboratory, Urbana, Illinois 61801, United States
| | - Kerry A Hamilton
- The School with Sustainable Engineering and the Built Environment and The Biodesign Institute Center for Environmental Health Engineering, Arizona State University, Tempe, Arizona 85287, United States
| | - Stephanie A Houser
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Avenue, 3221 Newmark Civil Engineering Laboratory, Urbana, Illinois 61801, United States
| | - Muwonge Mubasira
- Community Integrated Development Initiatives, P.O. Box 764, Kampala, Uganda
| | - David Katende
- Community Integrated Development Initiatives, P.O. Box 764, Kampala, Uganda
| | - Hannah A C Lohman
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Avenue, 3221 Newmark Civil Engineering Laboratory, Urbana, Illinois 61801, United States
| | - John T Trimmer
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Avenue, 3221 Newmark Civil Engineering Laboratory, Urbana, Illinois 61801, United States
| | - Noble Banadda
- Department of Agricultural & Biosystems Engineering, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Assata Zerai
- Department of Sociology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Jeremy S Guest
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Avenue, 3221 Newmark Civil Engineering Laboratory, Urbana, Illinois 61801, United States
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13
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Owens CEL, Cox PT, Byleveld PM, Osborne NJ, Rahman MB. Indigenous microbial surrogates in wastewater used to understand public health risk expressed in the Disability-Adjusted Life Year (DALY) metric. MICROBIOLOGY AUSTRALIA 2021. [DOI: 10.1071/ma21037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In any wastewater recycling scheme, the protection of public health is of primary importance. In Australia, the public health requirements applying to the treatment of recycled water are stringent. They use the Disability-Adjusted Life Year (DALY) metric to set a level of negligible public health risk. The target maximum risk of 10–6 DALY per person per year has been adopted in Australian water recycling guidelines since 2006. A key benefit of the DALY approach is its ability to standardise the understanding of risk across disparate areas of public health. To address the key challenge of translating the results of monitoring of microorganisms in the recycled water into this quantitative public health metric, we have developed a novel method. This paper summarises an approach where microbial surrogate organisms indigenous to wastewater are used to measure the efficiency of water recycling treatment processes and estimate public health risk. An example of recent implementation in the Greater Sydney region of Australia is provided.
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14
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Life-Cycle Assessment of the Wastewater Treatment Technologies in Indonesia’s Fish-Processing Industry. ENERGIES 2020. [DOI: 10.3390/en13246591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this paper, a comprehensive life-cycle assessment (LCA) is carried out in order to evaluate the multiple environmental-health impacts of the biological wastewater treatment of the fish-processing industry throughout its life cycle. To this aim, the life-cycle impact assessment method based on endpoint modeling (LIME) was considered as the main LCA model. The proposed methodology is based on an endpoint modeling framework that uses the conjoint analysis to calculate damage factors for human health, social assets, biodiversity, and primary production, based on Indonesia’s local data inventory. A quantitative microbial risk assessment (QMRA) is integrated with the LIME modeling framework to evaluate the damage on human health caused by five major biological treatment technologies, including chemical-enhanced primary clarification (CEPC), aerobic-activated sludge (AS), up-flow anaerobic sludge blanket (UASB), ultrafiltration (UF) and reverse osmosis (RO) in this industry. Finally, a life-cycle costing (LCC) is carried out, considering all the costs incurred during the lifetime. The LCA results revealed that air pollution and gaseous emissions from electricity consumption have the most significant environmental impacts in all scenarios and all categories. The combined utilization of the UF and RO technologies in the secondary and tertiary treatment processes reduces the health damage caused by microbial diseases, which contributes significantly to reducing overall environmental damage.
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15
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Ishaq S, Sadiq R, Farooq S, Chhipi-Shrestha G, Hewage K. Investigating the public health risks of low impact developments at residential, neighbourhood, and municipal levels. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 744:140778. [PMID: 32717466 PMCID: PMC7336927 DOI: 10.1016/j.scitotenv.2020.140778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 05/04/2023]
Abstract
Low Impact Developments (LIDs) employ a series of vegetative techniques to retain rainfall close to the site of origin. Although LIDs offer sustainable runoff management, these infrastructures can be considered a risk to public health due to the presence of pathogens in the runoff and human exposure to contaminated water held in and transported by LIDs. The objective of this study is to examine the disease burden of Gastrointestinal illness (GI) from exposure to LIDs at the residential, neighbourhood, and municipal levels. The authors conducted a meta-analysis of literature on three water features: (1) harvested rainwater obtained from LIDs, (2) surface water, and (3) floodwater. A set of 32 studies were systematically selected to collect values of risks of infection and expressed as the disease burden, i.e. disability adjusted life years (DALYs). The results showed that the percentage of GI illness exceeding the health guidelines were high for harvested rainwater, i.e. 22% of annual disease burden exceeded the WHO guidelines (0.001 DALYs/1000 persons), and 2% exceeded the US EPA guidelines (5.75 DALYs/1000 bathers). Among the six exposures for harvested rainwater, exposure to spray irrigation, exceeded US EPA guidelines whereas; five exposures, i.e. flushing, hosing, daily shower, spray irrigation, and children playing, surpassed the WHO guidelines. Considering LID treatment, the values of annual disease burden from all the selected barriers were below US EPA guidelines however, these values exceeded the WHO guidelines for three barriers i.e. water plaza, grass swale, and open storage ponds. These findings provide a broader perspective of the disease burden associated with LIDs and emphasise to consider the type of exposures and required treatment barriers for developing LID infrastructures in urban areas.
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Affiliation(s)
- Sadia Ishaq
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
| | - Rehan Sadiq
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
| | - Shaukat Farooq
- King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, 31261, Saudi Arabia
| | - Gyan Chhipi-Shrestha
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
| | - Kasun Hewage
- School of Engineering, University of British Columbia, Okanagan Campus, Kelowna, BC V1V 1V7, Canada.
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16
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Wachira VK, Nascimento GL, Peixoto HM, de Oliveira MRF. Burden of Disease of Guillain-Barré Syndrome in Brazil before and during the Zika virus epidemic 2014-2016. Trop Med Int Health 2020; 26:66-81. [PMID: 33151584 DOI: 10.1111/tmi.13508] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To estimate the burden of disease of Guillain-Barré syndrome (GBS) in Brazil in 2014, 1 year before the Zika virus epidemic, and in 2015 and 2016 during the epidemic. METHODS The burden of disease of GBS was estimated using the summary measure of population health: Disability Adjusted Life Years (DALY), that combines both mortality (Years of Life Lost YLLs) and morbidity (Years Lived with Disability) components. The study population was composed of GBS hospitalised cases and deaths from the information systems of the Brazilian Unified Health System. RESULTS The GBS incidence rate in 2014, 2015 and 2016 was 0.74, 0.96, 1.02/100 000 respectively, and the mortality rate in the same period was 0.08, 0.009 and 0.11/100 000 habitants. The DALYs calculated using the point estimate of GBS disability weight and its values of the confidence interval (0.198 and 0.414) were 5725.90 (5711.79-5742.89) in 2014, 6054.61 (6035.57-6077.54) in 2015 and 7588.49 (7570.20-7610.51) in 2016. The DALYs were high among the male population and in age groups between 20 and 50 years. CONCLUSIONS The increase in DALYs in the years 2015 and 2016 compared to 2014 probably resulted from the introduction of ZIKV in Brazil, reinforcing the importance of investments in the prevention of ZIKV infection and in the care of GBS patients.
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Affiliation(s)
- Virginia Kagure Wachira
- Center of Tropical Medicine, Faculty of Medicine, Universidade de Brasília, Brasília, Brazil
| | | | - Henry Maia Peixoto
- Center of Tropical Medicine, Faculty of Medicine, Universidade de Brasília, Brasília, Brazil.,National Institute of Science and Technology for Health Technology Assessment, Porto Alegre, Brazil
| | - Maria Regina Fernandes de Oliveira
- Center of Tropical Medicine, Faculty of Medicine, Universidade de Brasília, Brasília, Brazil.,National Institute of Science and Technology for Health Technology Assessment, Porto Alegre, Brazil
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17
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Riches A, Hart CJS, Trenholme KR, Skinner-Adams TS. Anti- Giardia Drug Discovery: Current Status and Gut Feelings. J Med Chem 2020; 63:13330-13354. [PMID: 32869995 DOI: 10.1021/acs.jmedchem.0c00910] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Giardia parasites are ubiquitous protozoans of global importance that impact a wide range of animals including humans. They are the most common enteric pathogen of cats and dogs in developed countries and infect ∼1 billion people worldwide. While Giardia infections can be asymptomatic, they often result in severe and chronic diseases. There is also mounting evidence that they are linked to postinfection disorders. Despite growing evidence of the widespread morbidity associated with Giardia infections, current treatment options are limited to compound classes with broad antimicrobial activity. Frontline anti-Giardia drugs are also associated with increasing drug resistance and treatment failures. To improve the health and well-being of millions, new selective anti-Giardia drugs are needed alongside improved health education initiatives. Here we discuss current treatment options together with recent advances and gaps in drug discovery. We also propose criteria to guide the discovery of new anti-Giardia compounds.
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Affiliation(s)
- Andrew Riches
- Commonwealth Scientific and Industrial Research Organization, Biomedical Manufacturing, Clayton, Victoria 3168, Australia
| | - Christopher J S Hart
- Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland 4111, Australia
| | - Katharine R Trenholme
- QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, Queensland 4029, Australia.,School of Medicine, University of Queensland, Brisbane, Queensland 4029, Australia
| | - Tina S Skinner-Adams
- Griffith Institute for Drug Discovery, Griffith University, Nathan, Queensland 4111, Australia
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18
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Kuhn KG, Nygård KM, Guzman-Herrador B, Sunde LS, Rimhanen-Finne R, Trönnberg L, Jepsen MR, Ruuhela R, Wong WK, Ethelberg S. Campylobacter infections expected to increase due to climate change in Northern Europe. Sci Rep 2020; 10:13874. [PMID: 32807810 PMCID: PMC7431569 DOI: 10.1038/s41598-020-70593-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 07/27/2020] [Indexed: 12/21/2022] Open
Abstract
Global climate change is predicted to alter precipitation and temperature patterns across the world, affecting a range of infectious diseases and particularly foodborne infections such as Campylobacter. In this study, we used national surveillance data to analyse the relationship between climate and campylobacteriosis in Denmark, Finland, Norway and Sweden and estimate the impact of climate changes on future disease patterns. We show that Campylobacter incidences are linked to increases in temperature and especially precipitation in the week before illness, suggesting a non-food transmission route. These four countries may experience a doubling of Campylobacter cases by the end of the 2080s, corresponding to around 6,000 excess cases per year caused only by climate changes. Considering the strong worldwide burden of campylobacteriosis, it is important to assess local and regional impacts of climate change in order to initiate timely public health management and adaptation strategies.
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Affiliation(s)
- Katrin Gaardbo Kuhn
- Infectious Disease Epidemiology and Prevention, Statens Serum Institut, Artillerivej 5, Copenhagen, Denmark.
| | - Karin Maria Nygård
- Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
| | - Bernardo Guzman-Herrador
- Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
| | - Linda Selje Sunde
- Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Oslo, Norway
| | - Ruska Rimhanen-Finne
- Department of Health Security, National Institute for Health and Welfare, Helsinki, Finland
| | - Linda Trönnberg
- Department of Monitoring and Evaluation, Public Health Agency of Sweden, Solna, Sweden
| | | | - Reija Ruuhela
- Weather and Climate Change Impact Research, Finnish Meteorological Institute, Helsinki, Finland
| | - Wai Kwok Wong
- Department of Hydrology, Norwegian Water Resources and Energy Directorate, Oslo, Norway
| | - Steen Ethelberg
- Infectious Disease Epidemiology and Prevention, Statens Serum Institut, Artillerivej 5, Copenhagen, Denmark
- Global Health Section, Department of Public Health, University of Copenhagen, Copenhagen, Denmark
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19
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Donato CM, Roczo-Farkas S, Kirkwood CD, Barnes GL, Bines JE. Rotavirus disease and genotype diversity in older children and adults in Australia. J Infect Dis 2020; 225:2116-2126. [PMID: 32692812 PMCID: PMC9200153 DOI: 10.1093/infdis/jiaa430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 08/13/2020] [Indexed: 11/14/2022] Open
Abstract
Background Rotavirus is a major cause of gastroenteritis in children <5 years of age. The disease burden in older children, adults, and the elderly is underappreciated. This study describes rotavirus disease and genotypic diversity in the Australian population comprising children ≥5 years of age and adults. Methods Rotavirus positive fecal samples were collected from laboratories Australia-wide participating in the Australian Rotavirus Surveillance Program between 2010 and 2018. Rotavirus samples were genotyped using a heminested multiplex reverse-transcription polymerase chain reaction. Notification data from the National Notifiable Diseases Surveillance System were also analyzed. Results Rotavirus disease was highest in children aged 5–9 years and adults ≥85 years. G2P[4] was the dominant genotype in the population ≥5 years of age. Genotype distribution fluctuated annually and genotypic diversity varied among different age groups. Geographical differences in genotype distribution were observed based on the rotavirus vaccine administered to infants <1 year of age. Conclusions This study revealed a substantial burden of rotavirus disease in the population ≥5 years of age, particularly in children 5–9 years and the elderly. This study highlights the continued need for rotavirus surveillance across the population, despite the implementation of efficacious vaccines.
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Affiliation(s)
- Celeste M Donato
- Enteric Diseases Group, Murdoch Children's Research Institute, Parkville, Australia.,Department of Paediatrics, The University of Melbourne, Parkville, Australia.,Biomedicine Discovery Institute and Department of Microbiology, Monash University, Melbourne, Australia
| | - Susie Roczo-Farkas
- Enteric Diseases Group, Murdoch Children's Research Institute, Parkville, Australia
| | - Carl D Kirkwood
- Enteric Diseases Group, Murdoch Children's Research Institute, Parkville, Australia.,Department of Paediatrics, The University of Melbourne, Parkville, Australia.,Enteric and Diarrheal Diseases, Global Health, Bill and Melinda Gates Foundation, Seattle, Washington, United States of America
| | - Graeme L Barnes
- Enteric Diseases Group, Murdoch Children's Research Institute, Parkville, Australia.,Department of Paediatrics, The University of Melbourne, Parkville, Australia.,Department of Gastroenterology and Clinical Nutrition, Royal Children's Hospital, Parkville, Australia
| | - Julie E Bines
- Enteric Diseases Group, Murdoch Children's Research Institute, Parkville, Australia.,Department of Paediatrics, The University of Melbourne, Parkville, Australia.,Department of Gastroenterology and Clinical Nutrition, Royal Children's Hospital, Parkville, Australia
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20
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Farhadkhani M, Nikaeen M, Hadi M, Gholipour S, Yadegarfar G. Campylobacter risk for the consumers of wastewater-irrigated vegetables based on field experiments. CHEMOSPHERE 2020; 251:126408. [PMID: 32171131 DOI: 10.1016/j.chemosphere.2020.126408] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/22/2020] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Water scarcity is emerging as a major problem in water stressed regions such as Middle East countries which highlights the importance of agricultural reuse of wastewater as a valid alternative source. However, consumption of wastewater-irrigated crops has been implicated as a vehicle for transmission of bacterial infections such as campylobacteriosis. Understanding and minimizing public health threats associated with agricultural reuse of treated wastewater (TWW) are crucial elements in sustainable water resource management. To address this need, the present study was carried out to determine Campylobacter risk for the consumers of TWW-irrigated vegetables by field experiments as well as quantitative microbial risk assessment (QMRA) model. Campylobacter was monitored in secondary treated wastewater, TWW-irrigated soil and harvested vegetables by nested real-time PCR assay. Campylobacter was detected in 64% (16/25) of TWW samples, whereas analysis of TWW-irrigated soil and vegetable samples yielded no positive result for Campylobacter. The estimated mean annual Campylobacter disease burden ranged from 2.37 × 10-5 to 6.6 × 10-5 disability-adjusted life years (DALYs) per person per year (pppy) for vegetable consumers which was lower than the less stringent reference level of 10-4 DALYs pppy has been recommended by world health organization (WHO). Our results in regard to the QMRA estimates and field experiments suggest that the reuse of TWW for irrigation of vegetables doesn't pose a considerable risk to human health from the viewpoint of Campylobacter infections in a semi-arid area.
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Affiliation(s)
- Marzieh Farhadkhani
- Student Research Committee and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahnaz Nikaeen
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Mahdi Hadi
- Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran
| | - Sahar Gholipour
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ghasem Yadegarfar
- Department of Statistics & Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
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21
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Cates JE, Vinjé J, Parashar U, Hall AJ. Recent advances in human norovirus research and implications for candidate vaccines. Expert Rev Vaccines 2020; 19:539-548. [PMID: 32500763 PMCID: PMC10760411 DOI: 10.1080/14760584.2020.1777860] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 06/01/2020] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Noroviruses are a leading cause of acute gastroenteritis worldwide. An estimated 21 million illnesses in the United States and upwards of 684 million illnesses worldwide are attributed to norovirus infection. There are no licensed vaccines to prevent norovirus, but several candidates are in development. AREAS COVERED We review recent advances in molecular epidemiology of noroviruses, immunology, and in-vitro cultivation of noroviruses using human intestinal enteroids. We also provide an update on the status of norovirus vaccine candidates. EXPERT OPINION Molecular epidemiological studies confirm the tremendous genetic diversity of noroviruses, the continuous emergence of new recombinant strains, and the predominance of GII.4 viruses worldwide. Duration of immunity, extent of cross protection between different genotypes, and differences in strain distribution for young children compared with adults remain key knowledge gaps. Recent discoveries regarding which epitopes are targeted by neutralizing antibodies using the novel in vitro culture of human noroviruses in human intestinal enteroids are enhancing our understanding of mechanisms of protection and providing guidance for vaccine development. A future norovirus vaccine has the potential to substantially reduce the burden of illnesses due to this ubiquitous virus.
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Affiliation(s)
- Jordan E Cates
- Division of Viral Diseases, Centers for Disease Control and Prevention , Atlanta, GA, USA
- Epidemic Intelligence Service, Centers for Disease Control and Prevention , Atlanta, GA, USA
| | - Jan Vinjé
- Division of Viral Diseases, Centers for Disease Control and Prevention , Atlanta, GA, USA
| | - Umesh Parashar
- Division of Viral Diseases, Centers for Disease Control and Prevention , Atlanta, GA, USA
| | - Aron J Hall
- Division of Viral Diseases, Centers for Disease Control and Prevention , Atlanta, GA, USA
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22
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Zahedi A, Odgers T, Ball A, Watkinson A, Robertson I, Ryan U. Longitudinal analysis of Giardia duodenalis assemblages in animals inhabiting drinking water catchments in New South Wales and Queensland - Australia (2013-2015). THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 718:137433. [PMID: 32105929 DOI: 10.1016/j.scitotenv.2020.137433] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 02/07/2020] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
Giardia duodenalis is one of the most common waterborne zoonotic parasites worldwide, and its occurrence in the environment and catchment reservoir water has serious implications for management of drinking water. The aim of the present study was to use molecular tools to identify the Giardia spp. infecting animals inhabiting five drinking water catchments across two states in Australia; New South Wales and Queensland, to better understand the potential health risks they pose. We used quantitative PCR to screen a total of 2174 faecal samples collected from dominant host species in catchment areas for the presence of G. duodenalis. All samples positive for G. duodenalis were further characterized and subtyped at tpi and gdh loci, respectively. The overall prevalence of G. duodenalis was 15.3% (332/2174, 95%CI; 13.8-16.9), and two zoonotic assemblages (assemblages A and B) and one potentially zoonotic assemblage (E) were detected in various host species. Additional subtyping of a subset of samples (n = 76) identified four human infectious sub-assemblages including AI, AII, BII-like and BIV-like, all of which have been previously reported in humans in Australia. The finding of zoonotic assemblages of G. duodenalis in the present study necessitates continued identification of the sources/carriers of human pathogenic strains in drinking water catchment areas for more accurate risk assessment and optimal catchment management.
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Affiliation(s)
- Alireza Zahedi
- College of Science, Health, Engineering and Education, Murdoch University, 6150 Perth, Australia.
| | - Tim Odgers
- Seqwater, Ipswich, Queensland, Australia
| | | | | | - Ian Robertson
- College of Science, Health, Engineering and Education, Murdoch University, 6150 Perth, Australia; China-Australia Joint Research and Training Center for Veterinary Epidemiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China
| | - Una Ryan
- College of Science, Health, Engineering and Education, Murdoch University, 6150 Perth, Australia
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23
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Fuzawa M, Smith RL, Ku KM, Shisler JL, Feng H, Juvik JA, Nguyen TH. Roles of Vegetable Surface Properties and Sanitizer Type on Annual Disease Burden of Rotavirus Illness by Consumption of Rotavirus-Contaminated Fresh Vegetables: A Quantitative Microbial Risk Assessment. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2020; 40:741-757. [PMID: 31742761 DOI: 10.1111/risa.13426] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/24/2019] [Accepted: 10/28/2019] [Indexed: 06/10/2023]
Abstract
Enteric viruses are often detected in water used for crop irrigation. One concern is foodborne viral disease via the consumption of fresh produce irrigated with virus-contaminated water. Although the food industry routinely uses chemical sanitizers to disinfect post-harvest fresh produce, it remains unknown how sanitizer and fresh produce properties affect the risk of viral illness through fresh produce consumption. A quantitative microbial risk assessment model was conducted to estimate (i) the health risks associated with consumption of rotavirus (RV)-contaminated fresh produce with different surface properties (endive and kale) and (ii) how risks changed when using peracetic acid (PAA) or a surfactant-based sanitizer. The modeling results showed that the annual disease burden depended on the combination of sanitizer and vegetable type when vegetables were irrigated with RV-contaminated water. Global sensitivity analyses revealed that the most influential factors in the disease burden were RV concentration in irrigation water and postharvest disinfection efficacy. A postharvest disinfection efficacy of higher than 99% (2-log10 ) was needed to decrease the disease burden below the World Health Organization (WHO) threshold, even in scenarios with low RV concentrations in irrigation water (i.e., river water). All scenarios tested here with at least 99.9% (3-log10 ) disinfection efficacy had a disease burden lower than the WHO threshold, except for the endive treated with PAA. The disinfection efficacy for the endive treated with PAA was only about 80%, leading to a disease burden 100 times higher than the WHO threshold. These findings should be considered and incorporated into future models for estimating foodborne viral illness risks.
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Affiliation(s)
- Miyu Fuzawa
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Rebecca Lee Smith
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Kang-Mo Ku
- Division of Plant and Soil Sciences, Davis College of Agriculture, Natural Resources and Design, West Virginia University, Morgantown, WV, USA
- Department of Horticulture, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 61886, Republic of Korea
| | - Joanna L Shisler
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Hao Feng
- Department of Food Science and Human Nutrition, College of Agricultural, Consumer and Environmental Sciences, Urbana, IL, USA
| | - John A Juvik
- Department of Crop Science, College of Agricultural, Consumer and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Thanh H Nguyen
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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24
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Tiash S, Saunders J, Hart CJS, Ryan JH, Riches AG, Skinner-Adams TS. An image-based Pathogen Box screen identifies new compounds with anti-Giardia activity and highlights the importance of assay choice in phenotypic drug discovery. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2020; 12:60-67. [PMID: 32234669 PMCID: PMC7113605 DOI: 10.1016/j.ijpddr.2020.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/04/2020] [Accepted: 03/06/2020] [Indexed: 02/07/2023]
Abstract
Giardia duodenalis, the most prevalent human intestinal parasite causes the disease, giardiasis. On an annual basis G. duodenalis infects ~1 billion people, of which ~280 million develop symptomatic disease. Giardiasis can be severe and chronic, causing malnutrition, stunted growth and poor cognitive development in children. Current treatment options rely on drugs with declining efficacy and side-effects. To improve the health and well-being of millions of people world-wide, new anti-Giardia drugs with different modes of action to currently used drugs are required. The Medicines for Malaria Venture's Pathogen Box, a collection of bio-active compounds specifically chosen to stimulate infectious disease drug discovery, represents an opportunity for the discovery of new anti-Giardia agents. While the anti-Giardia activity of Pathogen Box compounds has been reported, this work failed to identify known anti-Giardia controls within the compound set. It also reported the activity of compounds previously screened and shown to be inactive by others, suggesting data may be inaccurate. Given these concerns the anti-Giardia activity of Pathogen Box compounds was re-assessed in the current study. Data from this work identified thirteen compounds with anti-Giardia IC50 values ≤2 μM. Five of these compounds were reference compounds (marketed drugs with known anti-microbial activity), or analogues of compounds with previously described anti-Giardia activity. However, eight, including MMV676358 and MMV028694, which demonstrated potent sub-μM IC50s against assemblage A, B and metronidazole resistant parasites (0.3 μM and 0.9 μM respectively), may represent new leads for future drug development. Interestingly, only four of these compounds were identified in the previously reported Pathogen Box screen highlighting the importance of assay selection and design when assessing compounds for activity against infectious agents. 13 compounds with anti-Giardia IC50 values < 2 μM were identified. 8 compounds represent new leads for drug development. MMV676358 and MMV028694 demonstrated the most promising acting. Data highlight the importance of assay selection and design in drug discovery.
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Affiliation(s)
- Snigdha Tiash
- Griffith Institute for Drug Discovery, Griffith University, 46 Don Young Rd, Nathan, Queensland, 4111, Australia
| | - Jake Saunders
- Griffith Institute for Drug Discovery, Griffith University, 46 Don Young Rd, Nathan, Queensland, 4111, Australia
| | - Christopher J S Hart
- Griffith Institute for Drug Discovery, Griffith University, 46 Don Young Rd, Nathan, Queensland, 4111, Australia
| | - John H Ryan
- Commonwealth Scientific and Industrial Research Organization, Biomedical Manufacturing, Bayview Av., Clayton, Victoria, 3168, Australia
| | - Andrew G Riches
- Commonwealth Scientific and Industrial Research Organization, Biomedical Manufacturing, Bayview Av., Clayton, Victoria, 3168, Australia
| | - Tina S Skinner-Adams
- Griffith Institute for Drug Discovery, Griffith University, 46 Don Young Rd, Nathan, Queensland, 4111, Australia.
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Pogreba-Brown K, Austhof E, Armstrong A, Schaefer K, Villa Zapata L, McClelland DJ, Batz MB, Kuecken M, Riddle M, Porter CK, Bazaco MC. Chronic Gastrointestinal and Joint-Related Sequelae Associated with Common Foodborne Illnesses: A Scoping Review. Foodborne Pathog Dis 2020; 17:67-86. [DOI: 10.1089/fpd.2019.2692] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Kristen Pogreba-Brown
- Epidemiology & Biostatistics Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona
| | - Erika Austhof
- Epidemiology & Biostatistics Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona
| | - Alexandra Armstrong
- Epidemiology & Biostatistics Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona
| | - Kenzie Schaefer
- Epidemiology & Biostatistics Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona
| | - Lorenzo Villa Zapata
- Epidemiology & Biostatistics Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona
| | | | | | - Maria Kuecken
- U.S. Food and Drug Administration, College Park, Maryland
| | - Mark Riddle
- Naval Medical Research Center, Silver Spring, Maryland
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Keerthirathne TP, Ross K, Fallowfield H, Whiley H. A Successful Technique for the Surface Decontamination of Salmonella enterica Serovar Typhimurium Externally Contaminated Whole Shell Eggs Using Common Commercial Kitchen Equipment. Foodborne Pathog Dis 2019; 17:404-410. [PMID: 31750744 DOI: 10.1089/fpd.2019.2734] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Eggs are a highly nutritious food source used in a wide range of food products. In Australia, eggs are a frequent source of foodborne salmonellosis outbreaks, associated with eggshell contamination with Salmonella enterica serovar Typhimurium (ST). Despite their potentially hazardous nature, raw eggs are often used and consumed in mayonnaise, mousse, ice cream and eggnog. The aim of this study was to develop a shell egg decontamination method that removed ST contamination from the outside of an egg without impacting its usability. The decontamination method was developed by the adaptation of a temperature-controlled water bath (commonly present in kitchens and associated with the sous-vide technique) for the surface decontamination of eggs. The outside of whole eggs was artificially inoculated with two ST strains. The eggs were decontaminated by placing in a sous-vide cooker with the water heated to 57°C. The remaining viable ST present on the whole shell egg, crushed shells, internal egg contents and sous-vide water were enumerated over time by culturing onto XLD agar. The quality of the uncontaminated heat-treated eggs was determined by measuring the Haugh unit, yolk index, albumen pH, thermocoagulation, and stability of foam. A blind control study was conducted to assess the acceptability and usability of the treated eggs by chefs and food handlers for the preparation of mayonnaise. Complete decontamination of ST was achieved by treating eggs for 9 min in the sous-vide cooker (57°C). No statistically significant difference was observed in the quality of treated eggs compared with nontreated eggs using the quality measurements and acceptability score from chefs. This method provides a simple approach that can be adopted by chefs and food handlers to obtain safe eggs before the preparation of raw egg products.
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Affiliation(s)
| | - Kirstin Ross
- Environmental Health Group, College of Science and Engineering, Flinders University, Adelaide, Australia
| | - Howard Fallowfield
- Environmental Health Group, College of Science and Engineering, Flinders University, Adelaide, Australia
| | - Harriet Whiley
- Environmental Health Group, College of Science and Engineering, Flinders University, Adelaide, Australia
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Wang X, You SH, Lien KW, Ling MP. Using disease-burden method to evaluate the strategies for reduction of aflatoxin exposure in peanuts. Toxicol Lett 2019; 314:75-81. [PMID: 31284020 DOI: 10.1016/j.toxlet.2019.07.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 06/05/2019] [Accepted: 07/04/2019] [Indexed: 12/31/2022]
Abstract
Aflatoxin is a fungal secondary metabolite with high toxicity that is capable of contaminating various types of food crops. It has been identified as a Group 1 human carcinogen by the International Agency for Research on Cancer. Chronic aflatoxin exposure has caused worldwide concern as a matter of public food safety. Peanuts and peanut products are the major sources of aflatoxin exposure. Therefore, some reduction interventions have been developed to minimize contamination throughout the peanut production chain. The purpose of this study is to estimate the efficacy of interventions in reducing the health impact of hepatocellular carcinoma caused by aflatoxin contamination in peanuts. The estimated total Disability-Adjusted Life Years (DALYs) were calculated using FDA-iRISK software. Six aflatoxin reduction strategies were evaluated, including good agricultural practice (GAP), biocontrol, Purdue Improved Crop Storage packaging, basic processing, ozonolysis, and ultraviolet irradiation. The results indicated that basic processing could prevent huge public health loss of 4,079.7-21,833 total DALYs per year. In addition, GAP and biocontrol were both found to be effective strategies in the farm field. Meanwhile, the other three interventions had limited effectiveness in reducing total DALYs. In conclusion, this study could help farmers, processing plants, and government policy makers to alleviate aflatoxin contamination issues in the peanut production chain.
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Affiliation(s)
- Xin Wang
- Department of Food Science, National Taiwan Ocean University, Keelung City, Taiwan
| | - Shu-Han You
- Institute of Food Safety and Risk Management, National Taiwan Ocean University, Keelung City, Taiwan
| | - Keng-Wen Lien
- Food and Drug Administration, Ministry of Health and Welfare, Taipei City, Taiwan; Institute of Food Science and Technology, National Taiwan University, Taipei City, Taiwan
| | - Min-Pei Ling
- Department of Food Science, National Taiwan Ocean University, Keelung City, Taiwan.
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Hoffmann S, Scallan Walter E. Acute Complications and Sequelae from Foodborne Infections: Informing Priorities for Cost of Foodborne Illness Estimates. Foodborne Pathog Dis 2019; 17:172-177. [PMID: 31593489 DOI: 10.1089/fpd.2019.2664] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Cost of foodborne illness (CoFI) estimates provide estimates of the overall impact of foodborne illnesses, including hospitalizations, long-term complications, and deaths. CoFI estimates are needed in countries that require cost-benefit analysis as part of the process of adopting new regulations, as is the case in the United States. Monetary estimates of the impact of disease also provide a meaningful way of communicating with the public about the impact of foodborne disease. In 2014, researchers at the U.S. Department of Agriculture, Economic Research Service (ERS), published CoFI estimates for 15 pathogens that account for roughly 95% of illnesses and deaths from the 31 major foodborne pathogens included in the Centers for Disease Control and Prevention (CDC) foodborne disease incidence estimates. ERS is currently updating their estimates to include all 31 known pathogens and unspecific agents included in CDC incidence estimates. CoFI estimates are based on quantitative models of the health outcomes people experience as a result of these illnesses and an assessment of the costs associated with these health outcomes. Research on the incidence of foodborne disease provides a starting point for this disease modeling, but it usually must be supplemented by other additional synthesis of research on acute complications and long-term health outcomes of different foodborne diseases. As part of its current work revising CoFI estimates, ERS convened a workshop attended by leading foodborne disease public health scientists to discuss how changes in scientific research on the incidence and outcomes of foodborne illnesses should inform the next revision of ERS's CoFI estimates. This article presents a summary, based on discussion at this workshop, of the state of scientific research available to inform updated economic modeling of the CoFI in the United States.
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Affiliation(s)
- Sandra Hoffmann
- Food Economics Division, USDA Economic Research Service, Washington, District of Columbia
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The disease burden associated with Campylobacter spp. in Germany, 2014. PLoS One 2019; 14:e0216867. [PMID: 31091282 PMCID: PMC6519833 DOI: 10.1371/journal.pone.0216867] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 04/30/2019] [Indexed: 11/19/2022] Open
Abstract
Bacteria of the genus Campylobacter are an important cause of human illness worldwide. Campylobacter infections are expressed as gastroenteritis and can lead to severe sequelae like reactive arthritis, Guillain-Barré syndrome, irritable bowel syndrome and inflammatory bowel disease. In Germany, Campylobacter-associated gastroenteritis cases are notifiable but there is no reporting obligation for the sequelaes and the disease burden is clearly underestimated. The aim of our study was to quantify reliably the current disease burden of all Campylobacter spp.-associated diseases for Germany with the method of disability-adjusted life years (DALYs). DALYs combine mortality and morbidity in a single summary measure, whereby one DALY represents the loss of one year in full health. For acute gastroenteritis, we estimated 967 DALYs of which only 484 DALYs were detected within the reporting system. Overall, we estimated that 8811 DALYs were caused by the campylobacter-related diseases known so far. 98% of the DALYs were associated with morbidity and 2% with mortality. Mortality was caused by the health outcomes Gastroenteritis and Guillain-Barré syndrome exclusively.
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Epidemiological Survey and Retrospective Analysis of Salmonella Infections between 2000 and 2017 in Warmia and Masuria Voivodship in Poland. ACTA ACUST UNITED AC 2019; 55:medicina55030074. [PMID: 30897848 PMCID: PMC6473649 DOI: 10.3390/medicina55030074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/26/2019] [Accepted: 03/15/2019] [Indexed: 11/17/2022]
Abstract
Background and Objectives: Salmonellosis is a major foodborne bacterial infection throughout the world. Epidemiological surveillance is one of the key factors to reduce the number of infections caused by this pathogen in both humans and animals. The first outcome measure was the prevalence of non-typhoid Salmonella (NTS) infections between 2000 and 2017 among the population of the predominantly agricultural and touristic Polish region of Warmia and Masuria (WaM). The second outcome measure was the comparison of the NTS hospitalization rate of all registered NTS cases, an investigation of the monthly reports of infections, and the exploration of the annual minimal and maximal NTS infection number in WaM in the above-mentioned time period. The last outcome was a comparison of the prevalence of NTS infections in the region and in its administrative districts by considering both rural and urban municipalities three years before and three years after the accession of Poland into the European Union (EU) in 2004. Materials and Methods: The total number of infections and hospitalizations in the 19 districts of the WaM voivodship in Poland was registered monthly between 2000–2017 by the Provincial Sanitary-Epidemiological Station in Olsztyn, Poland. Results: Between 2000 and 2017, the number of diagnosed salmonellosis cases decreased significantly in WaM; the decrease was higher in urban districts than in rural ones, and the ratio of hospitalizations and the total number of NTS cases increased significantly across all districts. The lowest number of cases was reported in the winter months and was stable from 2007, whereas the highest number was reported in the summer months with a higher tendency of outbreaks. Conclusion: The falling number of salmonellosis cases in 2000–2017 in WaM reflects the general trend in Poland and Europe. The decrease of NTS infections in WaM is related to the accession of Poland into the EU.
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Harris JP, Iturriza-Gomara M, O'Brien SJ. Estimating Disability-Adjusted Life Years (DALYs) in Community Cases of Norovirus in England. Viruses 2019; 11:v11020184. [PMID: 30795617 PMCID: PMC6410119 DOI: 10.3390/v11020184] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/15/2019] [Accepted: 02/19/2019] [Indexed: 12/14/2022] Open
Abstract
Disability adjusted life years (DALYs) have been used since the 1990s. It is a composite measure of years of life lost with years lived with disability. Essentially, one DALY is the equivalent of a year of healthy life lost if a person had not experienced disease. Norovirus is the most common cause of gastrointestinal diseases worldwide. Norovirus activity varies from one season to the next for reasons not fully explained. Infection with norovirus is generally not severe, and is normally characterized as mild and self-limiting with no long-term sequelae. In this study, we model a range of estimates of DALYs for community cases of norovirus in England and Wales. We estimated a range of DALYs for norovirus to account for mixing of the severity of disease and the range of length of illness experienced by infected people. Our estimates were between 1159 and 4283 DALYs per year, or 0.3⁻1.2 years of healthy life lost per thousand cases of norovirus. These estimates provide evidence that norovirus leads to a considerable level of ill health in England and Wales. This information will be helpful should candidate norovirus vaccines become available in the future.
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Affiliation(s)
- John P Harris
- Institute of Population Health Sciences, University of Liverpool, Liverpool, L69 3GL, UK.
- National Institute for Health Research (NIHR), Health Protection Research Unit (HPRU) in Gastrointestinal Infections, Liverpool, L69 3GL, UK.
| | - Miren Iturriza-Gomara
- National Institute for Health Research (NIHR), Health Protection Research Unit (HPRU) in Gastrointestinal Infections, Liverpool, L69 3GL, UK.
- Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE, UK.
| | - Sarah J O'Brien
- Institute of Population Health Sciences, University of Liverpool, Liverpool, L69 3GL, UK.
- National Institute for Health Research (NIHR), Health Protection Research Unit (HPRU) in Gastrointestinal Infections, Liverpool, L69 3GL, UK.
- Modelling, Evidence and Policy Research Group, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.
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Xiao S, Yin P, Zhang Y, Zhao X, Sun L, Yuan H, Lu J, Hu S. Occurrence, genotyping, and health risk of Cryptosporidium and Giardia in recreational lakes in Tianjin, China. WATER RESEARCH 2018; 141:46-56. [PMID: 29775772 DOI: 10.1016/j.watres.2018.05.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/09/2018] [Accepted: 05/10/2018] [Indexed: 06/08/2023]
Abstract
Cryptosporidium and Giardia are critical parasites in the etiology of diarrhea worldwide, and often cause waterborne outbreaks. The presence of Cryptosporidium and Giardia in recreational lakes was investigated with molecular characterization, and a comprehensive quantitative microbial risk assessment (QMRA) of protozoan infections was performed, considering multiple exposure pathways, differences in age, sex, and disease severity, and the genotypes of the protozoa. Forty-three (82.7%) and 51 (98.1%) water samples were positive for Cryptosporidium oocysts and Giardia cysts, respectively, with average counts of 3.65 oocysts/10 L and 12.58 cysts/10 L, respectively. Six Cryptosporidium species and three Giardia lamblia assemblages were confirmed with molecular analyses. The protozoan concentration was significantly associated with water turbidity, but not with the total coliform numbers. Swimming in the lakes entailed the highest incidence risk of 5.72 × 10-4 per person per year (pppy) (95% confidence interval (CI): 0.03-43.33 × 10-4) for Cryptosporidium and 4.04 × 10-4 pppy (95% CI: 0.01-32.66 × 10-4) for Giardia, whereas wading entailed the lowest risk (2.20 × 10-4 and 1.70 × 10-4 pppy, respectively). The annual burdens attributable to recreational-water-associated cryptosporidiosis and giardiasis were 3.44 (95% CI: 0.04-23.51) and 1.81 (95% CI: 0.01-12.96) disability-adjusted life years per 1,000,000 individuals per year, respectively. Children were more likely to have an individual disease burden than adults, and males were more likely than females. Sensitivity analysis highlighted the great importance of controlling the proportion of exposed individuals and reducing the frequency of exposure. The methodology and results of this study will allow us to better evaluate and reduce the burden of Cryptosporidium and/or Giardia infections associated with recreational water use in China and other countries.
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Affiliation(s)
- Shumin Xiao
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China; Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin 300384, PR China.
| | - Pengna Yin
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Yan Zhang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Xiaoyun Zhao
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Liping Sun
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Hongying Yuan
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Jingfang Lu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Sike Hu
- School of Medicine, Nankai University, Tianjin 300071, PR China.
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Zommiti M, Almohammed H, Ferchichi M. Purification and Characterization of a Novel Anti-Campylobacter Bacteriocin Produced by Lactobacillus curvatus DN317. Probiotics Antimicrob Proteins 2018; 8:191-201. [PMID: 27812926 DOI: 10.1007/s12602-016-9237-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The lactic acid bacteria (LAB) microbiota of Saudi chicken ceca was determined. From 60 samples, 204 isolates of lactic acid bacteria were obtained. Three isolates produced antimicrobial activities against Campylobacter jejuni, Listeria monocytogenes, and Bacillus subtilis. The isolate DN317, which had the highest activity against Campylobacter jejuni ATCC 33560, was identified as Lactobacillus curvatus (GenBank accession numbers: KX353849 and KX353850). Full inhibitory activity was observed after a 2-h incubation with the supernatant at pH values between 4 and 8. Only 16% of the activity was conserved after a treatment at 121 °C for 15 min. The use of proteinase K, pepsin, chymotrypsin, trypsin, papain, and lysozyme drastically reduced the antimicrobial activity. However, lipase, catalase, and lysozyme had no effect on this activity. The active peptide produced by Lactobacillus curvatus DN317 was purified by precipitation with an 80% saturated ammonium sulfate solution, and two steps of reversed phase HPLC on a C18 column. The molecular weight of this peptide was 4448 Da as determined by MALDI-ToF. N-terminal sequence analysis using Edman degradation revealed 47 amino acid residues (UniProt Knowledgebase accession number C0HK82) revealing homology with the amino acid sequences of sakacin P and curvaticin L442. The antimicrobial activity of the bacteriocin, namely curvaticin DN317, was found to be bacteriostatic against Campylobacter jejuni ATCC 33560. The use of microbial antagonism by LAB is one of the best ways to control microorganisms safely in foods. This result constitutes a reasonable advance in the antimicrobial field because of its potential applications in food technology.
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Affiliation(s)
- Mohamed Zommiti
- Unité de Protéomique Fonctionnelle et Potentiel Nutraceutique de la Biodiversité de Tunisie, Institut Supérieur des Sciences Biologiques Appliquées de Tunis, Rue Z. Essafi, 1006, Tunis, Tunisia
| | - Hamdan Almohammed
- Department of Medical Microbiology and Parasitology, College of Medicine, King Faisal University, P.O. Box: 400, Al-Ahsa, 31982, Saudi Arabia
| | - Mounir Ferchichi
- Unité de Protéomique Fonctionnelle et Potentiel Nutraceutique de la Biodiversité de Tunisie, Institut Supérieur des Sciences Biologiques Appliquées de Tunis, Rue Z. Essafi, 1006, Tunis, Tunisia.
- College of Applied Medical Sciences, Clinical Laboratory Department, King Faisal University, P.O. Box: 401, Al-Ahsa, 31982, Saudi Arabia.
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Gastroenteritis outbreak at a health function caused by an emerging recombinant strain of Norovirus GII.P16/GII.4 Sydney 2012, Australia. Epidemiol Infect 2018; 146:970-971. [DOI: 10.1017/s0950268818000869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
AbstractAn emerging recombinant norovirus GII.P16/GII.4 Sydney 2012 strain caused a gastroenteritis outbreak amongst attendees at a large health function in regional New South Wales, Australia. This was the third outbreak caused by the recombinant GII.P16/GII.4 Sydney 2012 strain in this region in 2017, which appears to be emerging as a common strain in the Hunter New England region.
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Cost of gastroenteritis in Australia: A healthcare perspective. PLoS One 2018; 13:e0195759. [PMID: 29649285 PMCID: PMC5896984 DOI: 10.1371/journal.pone.0195759] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 03/28/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Acute gastroenteritis illness is a common illness that causes considerable morbidity, but current estimates of the cost to the Australian healthcare system are unknown. OBJECTIVE To estimate the current healthcare utilisation and direct public healthcare system costs attributable to acute gastroenteritis illness in Australia. METHODS This is an incidence-based cost-of-illness study focused on quantifying direct health care costs using a bottom-up approach. Data on general practitioner consultations, prescribed medications, diagnostic tests, specialist consultations, emergency department visits and hospital admissions were collected from national reports. RESULTS Using 2016 prices, the estimated annual direct per capita cost of acute gastroenteritis illness was AUD$14.87 (USD$10.71), equating to AUD$20.27 (USD$14.59) per case. The estimated overall economic burden in Australia was AUD$359 million (USD$258 million; AUD$1.5 million per 100,000 people). The major contributors to this cost were hospital admissions (57.1%), emergency department visits (17.7%), and general practitioner consultations (14.0%). Children under five years of age have the highest per capita rates of acute gastroenteritis illness; however, service utilisation rates vary by age group and both young children and older adults accounted for a substantial proportion of the overall economic burden attributable to acute gastroenteritis illness. CONCLUSIONS Although chronic diseases comprise a large cost burden on the healthcare system, acute illnesses, including acute gastroenteritis illness, also impose substantial direct healthcare system costs. Providing data on current cost estimates is useful for prioritizing public health interventions, with our findings suggesting that it would be ideal if targeted interventions to reduce hospitalisation rates among young children and older adults were available.
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Villalba-Vizcaíno V, Buelvas Y, Arroyo-Salgado B, Castro LR. Molecular identification of Giardia intestinalis in two cities of the Colombian Caribbean Coast. Exp Parasitol 2018; 189:1-7. [PMID: 29627329 DOI: 10.1016/j.exppara.2018.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 03/20/2018] [Accepted: 04/04/2018] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Parasitoses are an important health problem and its post-infectious consequences can cause high morbidity and mortality, worldwide. Epidemiological data is scarce in our region. We aimed to obtain frequency and circulating genotypes of Giardia intestinalis in two cities of the Caribbean Coast. METHODS To identify parasites in samples, a fecal concentration and microscopical examination were performed. For further identification and genotyping of G. intestinalis, molecular analyses were performed using specific available primers. RESULTS Only 22.1% of participants had gastrointestinal symptoms (most frequently: abdominal pain and diarrhea). Microscopy examination was positive in 72.7% of the samples. The most frequent parasite was G. intestinalis (48.1%) and we found mixed parasitic infections in 46.7% of the participants. All the samples from Santa Marta were molecularly characterized as assemblage A of G. intestinalis, while in Cartagena we confirmed the presence of assemblages A and B. CONCLUSIONS Molecular tools are important in the diagnosis of parasites and to increase comprehension of their distribution. In this study, a higher frequency of parasites, mostly protozoa, was observed.
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Affiliation(s)
- Vivian Villalba-Vizcaíno
- Grupo de Evolución, Sistemática y Ecología Molecular, Universidad del Magdalena, Carrera 32 # 22-08, Santa Marta, Colombia; Grupo de Investigación en Inmunología y Patología (GIPAT), Universidad del Magdalena, Colombia.
| | | | - Barbara Arroyo-Salgado
- Facultad de Medicina, Grupo de Investigaciones Microbiológicas de la Universidad de Cartagena, Cartagena, Colombia
| | - Lyda R Castro
- Grupo de Evolución, Sistemática y Ecología Molecular, Universidad del Magdalena, Carrera 32 # 22-08, Santa Marta, Colombia
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Xiao S, Hu S, Zhang Y, Zhao X, Pan W. Influence of sewage treatment plant effluent discharge into multipurpose river on its water quality: A quantitative health risk assessment of Cryptosporidium and Giardia. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 233:797-805. [PMID: 29141237 DOI: 10.1016/j.envpol.2017.11.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/15/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
Sewage treatment plants (STPs) are one of the sources of pathogens discharged into surface water. An investigation was carried out over the duration of 12 months in Henan Province, China, to evaluate the health influence of municipal wastewater effluent discharge on water quality of the receiving water. A discharge-based quantitative microbial risk assessment (QMRA) was employed, taking into account the vegetables consumption habits of the Chinese, population subgroups with different immune statuses and ages, to evaluate the incremental disease burden from agricultural irrigation and swimming exposure scenarios associated with increased concentration of the protozoan Cryptosporidium and/or Giardia in the receiving river. The results shown that all the STP influent samples contained Cryptosporidium and Giardia with average density of 142.31 oocysts/L and 1187.06 cysts/L, respectively. The QMRA results demonstrated that the estimated additional health burdens due to discharged effluent for both parasites were slightly violated the threshold of 10-6 DALYs per person per year set by WHO. Mitigation measures should be planned and executed by season since more disease burdens were borne during hot season than other seasons. The sensitivity analysis highlighted the great importance of stability of STP treatment process. This study provides useful information to improve the safety of surface water and deduce the disease burden of the protozoa in Henan Province and other region inside and outside China.
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Affiliation(s)
- Shumin Xiao
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China; Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin 300384, PR China.
| | - Sike Hu
- School of Medicine, Nankai University, Tianjin 300071, PR China.
| | - Yan Zhang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Xiaoyun Zhao
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China
| | - Wenwei Pan
- College of Resources and Environment, Henan Polytechnic University, Jiaozuo 454000, PR China
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Chhipi-Shrestha G, Hewage K, Sadiq R. Fit-for-purpose wastewater treatment: Conceptualization to development of decision support tool (I). THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 607-608:600-612. [PMID: 28709094 DOI: 10.1016/j.scitotenv.2017.06.269] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Revised: 06/29/2017] [Accepted: 06/30/2017] [Indexed: 06/07/2023]
Abstract
This article is the first in a series of two papers. Paper I focuses on model conceptualization and development, and Paper II in the series focuses on model validation and implementation. The amount of water reuse has been increasing across the globe. Wastewater can be treated based on the intended end use of reclaimed water. Fit-for-purpose wastewater treatment (WWT) simultaneously considers intended end use, economic viability, and environmental sustainability. WWT technologies differ mainly in terms of treatment efficiency, cost, energy use, and associated carbon emissions. The planning and evaluation of water reuse projects requires a decision support tool (DST) to evaluate alternative WWT trains and water reuse applications. However, such a DST is not available in the publically accessible literature. A DST, FitWater, has been developed for the evaluation of WWT for various urban reuses. The evaluation is based on the following criteria: amount of reclaimed water production, health risk of water reuse, cost, energy use, and carbon emissions. The cost is estimated as annualized life cycle cost and health risk is estimated using quantitative microbial risk assessment. The uncertainty analysis has been performed using probabilistic and fuzzy-based methods. A multi-criteria decision analysis, using fuzzy weighted average, is employed to aggregate different criteria and generate a final score. FitWater ranks alternative WWT trains based on the resulting final score. The proposed FitWater DST is user-friendly, and its application is demonstrated using an example. The DST can be enhanced to include additional treatment technologies and carbon emissions of different treatment processes.
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Affiliation(s)
- Gyan Chhipi-Shrestha
- School of Engineering, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna, BC V1V 1V7, Canada.
| | - Kasun Hewage
- School of Engineering, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna, BC V1V 1V7, Canada
| | - Rehan Sadiq
- School of Engineering, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna, BC V1V 1V7, Canada
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Differences in the occurrence and epidemiology of cryptosporidiosis in Aboriginal and non-Aboriginal people in Western Australia (2002 − 2012). INFECTION GENETICS AND EVOLUTION 2017; 53:100-106. [DOI: 10.1016/j.meegid.2017.05.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 05/16/2017] [Accepted: 05/20/2017] [Indexed: 01/08/2023]
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The effects of ambient temperature and heatwaves on dailyCampylobactercases in Adelaide, Australia, 1990–2012. Epidemiol Infect 2017; 145:2603-2610. [DOI: 10.1017/s095026881700139x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
SUMMARYCampylobacterspp. is a commonly reported food-borne disease with major consequences for morbidity. In conjunction with predicted increases in temperature, proliferation in the survival of microorganisms in hotter environments is expected. This is likely to lead, in turn, to an increase in contamination of food and water and a rise in numbers of cases of infectious gastroenteritis. This study assessed the relationship ofCampylobacterspp. with temperature and heatwaves, in Adelaide, South Australia.We estimated the effect of (i) maximum temperature and (ii) heatwaves on dailyCampylobactercases during the warm seasons (1 October to 31 March) from 1990 to 2012 using Poisson regression models.There was no evidence of a substantive effect of maximum temperature per 1 °C rise (incidence rate ratio (IRR) 0·995, 95% confidence interval (95% CI) 0·993–0·997) nor heatwaves (IRR 0·906, 95% CI 0·800–1·026) onCampylobactercases. In relation to heatwave intensity, which is the daily maximum temperature during a heatwave, notifications decreased by 19% within a temperature range of 39–40·9 °C (IRR 0·811, 95% CI 0·692–0·952). We found little evidence of an increase in risk and lack of association betweenCampylobactercases and temperature or heatwaves in the warm seasons. Heatwave intensity may play a role in that notifications decreased with higher temperatures. Further examination of the role of behavioural and environmental factors in an effort to reduce the risk of increasedCampylobactercases is warranted.
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Abstract
Salmonella enterica subspecies enterica includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains. Having studied host-pathogen interactions, microbiologists and immunologists argue in favor of topical gastrointestinal administration for improvement in vaccine efficacy. Here, recent advances in this field are summarized, including mechanisms of bacterial uptake at the intestinal epithelium, the assessment of protective host immunity, and improved animal models that closely mimic infection in humans. The pros and cons of existing vaccines are presented, along with recent progress made with novel formulations. Finally, new candidate antigens and their relevance in the refined design of anti-Salmonella vaccines are discussed, along with antigen vectorization strategies such as nanoparticles or secretory immunoglobulins, with a focus on potentiating mucosal vaccine efficacy.
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Gibney KB, O'Toole J, Sinclair M, Leder K. Burden of Disease Attributed to Waterborne Transmission of Selected Enteric Pathogens, Australia, 2010. Am J Trop Med Hyg 2017; 96:1400-1403. [PMID: 28719263 PMCID: PMC5462579 DOI: 10.4269/ajtmh.16-0907] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 02/07/2017] [Indexed: 01/23/2023] Open
Abstract
AbstractUniversal access to safe drinking water is a global priority. To estimate the annual disease burden of campylobacteriosis, nontyphoidal salmonellosis, cryptosporidiosis, giardiasis, and norovirus attributable to waterborne transmission in Australia, we multiplied regional World Health Organization (WHO) estimates of the proportion of cases attributable to waterborne transmission by estimates of all-source disease burden for each study pathogen. Norovirus was attributed as causing the most waterborne disease cases (479,632; 95% uncertainty interval [UI]: 0-1,111,874) followed by giardiasis and campylobacteriosis. The estimated waterborne disability-adjusted life year (DALY) burden for campylobacteriosis (2,004; 95% UI: 0-5,831) was 7-fold greater than other study pathogens and exceeded the WHO guidelines for drinking water quality (1 × 10-6 DALY per person per year) by 90-fold. However, these estimates include disease transmitted via either drinking or recreational water exposure. More precise country-specific and drinking water-specific attribution estimates would better define the health burden from drinking water and inform changes to treatment requirements.
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Affiliation(s)
- Katherine B. Gibney
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and the Royal Melbourne Hospital, Victoria, Australia
- Department of Epidemiology and Preventive Medicine, Monash University, Victoria, Australia
| | - Joanne O'Toole
- Department of Epidemiology and Preventive Medicine, Monash University, Victoria, Australia
| | - Martha Sinclair
- Department of Epidemiology and Preventive Medicine, Monash University, Victoria, Australia
| | - Karin Leder
- Department of Epidemiology and Preventive Medicine, Monash University, Victoria, Australia
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Turonova H, Haddad N, Hernould M, Chevret D, Pazlarova J, Tresse O. Profiling of Campylobacter jejuni Proteome in Exponential and Stationary Phase of Growth. Front Microbiol 2017; 8:913. [PMID: 28572800 PMCID: PMC5435804 DOI: 10.3389/fmicb.2017.00913] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 05/04/2017] [Indexed: 12/25/2022] Open
Abstract
Campylobacter jejuni has been reported as a major cause of bacterial food-borne enteritides in developed countries during the last decade. Despite its fastidious growth requirements, including low level of oxygen and high level of CO2, this pathogen is able to persist in the environment without permanent loss of its viability and virulence. As C. jejuni is not able to multiply outside a host, the cells spend significant amount of time in stationary phase of growth. The entry into the stationary phase is often correlated to resistance to various stresses in bacteria. The switching between exponential and stationary phases is frequently mediated by the regulator sigma S (RpoS). However, this factor is absent in C. jejuni and molecular mechanisms responsible for transition of cells to the stationary phase remain elusive. In this work, proteomic profiles of cells from exponential and stationary phases were compared using 2-D electrophoresis (2DE) fingerprinting combined with mass spectrometry analysis and qRT-PCR. The identified proteins, whose expression differed between the two phases, are mostly involved in protein biosynthesis, carbon metabolism, stress response and motility. Altered expression was observed also in the pleiotropic regulator CosR that was over-expressed during stationary phase. A shift between transcript and protein level evolution of CosR throughout the growth of C. jejuni was observed using qRT-PCR and (2DE). From these data, we hypothesized that CosR could undergo a negative autoregulation in stationary phase. A consensus sequence resulting from promoter sequence alignment of genes potentially regulated by CosR, including its own upstream region, among C. jejuni strains is proposed. To verify experimentally the potential autoregulation of CosR at the DNA level, electrophoretic mobility shift assay was performed with DNA fragments of CosR promoter region and rCosR. Different migration pattern of the promoter fragments indicates the binding capacity of CosR, suggesting its auto-regulation potential.
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Affiliation(s)
- Hana Turonova
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and TechnologyPrague, Czechia
| | - Nabila Haddad
- SECALIM UMR1014, Institut National de la Recherche AgronomiqueNantes, France
| | - Mathieu Hernould
- SECALIM UMR1014, Institut National de la Recherche AgronomiqueNantes, France
| | - Didier Chevret
- UMR1319 MICALIS, Plateforme d'Analyse Protéomique de Paris Sud-Ouest, Institut National de la Recherche AgronomiqueJouy-en-Josas, France
| | - Jarmila Pazlarova
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and TechnologyPrague, Czechia
| | - Odile Tresse
- SECALIM UMR1014, Institut National de la Recherche AgronomiqueNantes, France
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Molecular typing of Giardia duodenalis in humans in Queensland - first report of Assemblage E. Parasitology 2017; 144:1154-1161. [PMID: 28482937 DOI: 10.1017/s0031182017000439] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Little is known about the genetic diversity of the protozoan parasite, Giardia duodenalis, infecting humans in Queensland, Australia. The present study typed 88 microscopically Giardia-positive isolates using assemblage-specific primers at the triose phosphate isomerase (tpi) gene and sequenced a subset of isolates at the glutamate dehydrogenase (gdh) gene (n = 30) and tpi locus (n = 27). Using the tpi-assemblage specific primers, G. duodenalis assemblage A and assemblage B were detected in 50% (44/88) and 38·6% (34/88) of samples, respectively. Mixed infections with assemblages A and B were identified in 4·5% (4/88) and assemblage E was identified in 6·8% (6/88) of samples. Sequence analysis at the gdh and tpi loci also confirmed the presence of assemblage E in these isolates. Cyst numbers per gram of feces (g-1) were determined using quantitative polymerase chain reaction and of the isolates that were typed as assemblage E, cyst numbers ranged 13·8-68·3 × 106 cysts g-1. This is the first report of assemblage E in humans in Australia, indicating that in certain settings, this assemblage may be zoonotic.
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45
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Sparham SJ, Kwong JC, Valcanis M, Easton M, Trott DJ, Seemann T, Stinear TP, Howden BP. Emergence of multidrug resistance in locally-acquired human infections with Salmonella Typhimurium in Australia owing to a new clade harbouring bla CTX-M-9. Int J Antimicrob Agents 2017; 50:101-105. [PMID: 28476613 DOI: 10.1016/j.ijantimicag.2017.02.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 02/06/2017] [Accepted: 02/10/2017] [Indexed: 10/19/2022]
Abstract
Antimicrobial resistance in non-typhoidal Salmonella is a critical problem globally, with the emergence of resistance to third-generation cephalosporins (3GCs) a particular concern. The aim of this study was to use whole-genome sequencing (WGS) to characterise recently identified human and non-human isolates of 3GC-resistant Salmonella enterica subsp. enterica serovar Typhimurium from Australia. The Illumina NextSeq sequencing platform was used to determine the genome sequences of 78 S. Typhimurium definitive type 44 isolated in Australia between 1992 and 2016, including 31 3GC-resistant isolates. Phylogenetic and bioinformatics analyses were subsequently performed using a number of in silico tools. We report the emergence of 3GC resistance in locally-acquired Australian S. Typhimurium for the first time. Phenotypically resistant isolates of human and animal origin were geographically restricted and were found by WGS all to be closely related and to carry blaCTX-M-9. Dairy cattle were the suspected source based on geographical clustering of animal isolates, which were predominantly bovine in origin. In conclusion, locally-acquired human cases of S. Typhimurium carrying blaCTX-M-9 were identified that appear to be of bovine origin, raising concerns regarding the human impact of off-label use of ceftiofur in cattle.
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Affiliation(s)
- Sarah J Sparham
- Microbiological Diagnostic Unit Public Health Laboratory, Melbourne, VIC, Australia; Infectious Diseases Department, Austin Health, Heidelberg, VIC, Australia
| | - Jason C Kwong
- Microbiological Diagnostic Unit Public Health Laboratory, Melbourne, VIC, Australia; Infectious Diseases Department, Austin Health, Heidelberg, VIC, Australia; Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia; Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Mary Valcanis
- Microbiological Diagnostic Unit Public Health Laboratory, Melbourne, VIC, Australia
| | - Marion Easton
- Department of Health and Human Services, Victorian Government, Australia
| | - Darren J Trott
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA, Australia
| | - Torsten Seemann
- Microbiological Diagnostic Unit Public Health Laboratory, Melbourne, VIC, Australia; Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia; Melbourne Bioinformatics, The University of Melbourne, Carlton, VIC, Australia
| | - Timothy P Stinear
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia; Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia
| | - Benjamin P Howden
- Microbiological Diagnostic Unit Public Health Laboratory, Melbourne, VIC, Australia; Infectious Diseases Department, Austin Health, Heidelberg, VIC, Australia; Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia; Department of Microbiology and Immunology, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Melbourne, VIC, Australia.
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Yang X, Jin K, Yang F, Yuan G, Liu W, Xiang L, Wu Z, Li Z, Mao J, Shen J, Lombe N, Zandamela H, Hazoume L, Hou X, Ding Y, Cao G. Nontyphoidal Salmonella Gastroenteritis in Baoshan, Shanghai, China, 2010 to 2014: An Etiological Surveillance and Case-Control Study. J Food Prot 2017; 80:482-487. [PMID: 28207307 DOI: 10.4315/0362-028x.jfp-16-309] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nontyphoidal Salmonella (NTS) gastroenteritis is a widespread global foodborne disease. To identify the epidemiologic characteristics, sources of food contamination, and risk factors of NTS gastroenteritis, epidemiologic data and stool specimens of diarrheal patients were collected from sentinel hospitals in Baoshan, Shanghai, People's Republic of China, between 2010 and 2014. Food products from nearby farmers' markets and animal feces from live poultry markets and livestock farms were sampled to identify the pathogen; a case-control study was conducted to characterize risk factors of NTS gastroenteritis. Of 3,906 diarrheal patients examined, 266 (6.8%) were positive for Salmonella. The positive rates were higher in summer than in the other seasons. Salmonella Typhimurium (36.1%) and Salmonella Enteritidis (30.8%) were the dominant serovars in the patients. Salmonella was detected in 26.2% pork samples, 7.1 to 7.8% poultry meats, and 3.3 to 8.9% poultry feces. Salmonella Typhimurium was the major serovar in contaminated food and animal feces. Multivariate conditional logistic regression analysis indicated that consumption of pork and quickly cooked eggs increased, whereas separating kitchen knives for cooked and raw food decreased the risk of NTS gastroenteritis, independently. We believe that NTS in poultry feces contaminated the meat products in the same markets and then infected humans if these foods were not sufficiently cooked. To prevent NTS gastroenteritis, it is necessary to survey Salmonella in meats and poultry feces, to cook eggs and pork sufficiently, to separate kitchen knives for cooked and raw food, and to prohibit live poultry trade in fresh meat markets.
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Affiliation(s)
- Xingtang Yang
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Kai Jin
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Fan Yang
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Guoping Yuan
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Wenbin Liu
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Lunhui Xiang
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Zhenqiang Wu
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Zixiong Li
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Jianying Mao
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Junqing Shen
- 1 Department of Infectious Diseases, Baoshan District Center for Disease Control and Prevention, 158 Yueming Road, Baoshan District, Shanghai 201901, People's Republic of China
| | - Nelson Lombe
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Hemitério Zandamela
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Lucrece Hazoume
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Xiaomei Hou
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Yibo Ding
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
| | - Guangwen Cao
- 2 Department of Epidemiology, Shanghai Key Laboratory of Medical Biodefense, Second Military Medical University, 800 Xiangyin Road, Yangpu District, Shanghai 200433, People's Republic of China
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Chhipi-Shrestha G, Hewage K, Sadiq R. Microbial quality of reclaimed water for urban reuses: Probabilistic risk-based investigation and recommendations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 576:738-751. [PMID: 27810759 DOI: 10.1016/j.scitotenv.2016.10.105] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/14/2016] [Accepted: 10/15/2016] [Indexed: 05/20/2023]
Abstract
Although Canada has abundant freshwater resources, many cities still experience seasonal water shortage. Supply-side and demand-side management is a core strategy to address this water shortage. Under this strategy, reclaimed water, which the Canadian public is willing to use for non-potable purposes, is an option. However, no universal guidelines exist for reclaimed water use. Despite the federal government's long-term goal to develop guidelines for many water reuse applications, guidelines have only been prescribed for reclaimed water use in toilet and urinal flushing in Canada. At the provincial level, British Columbia (BC) has promulgated guidelines for wide applications of reclaimed water but only at broad class levels. This research has investigated and proposed probabilistic risk-based recommended values for microbial quality of reclaimed water in various non-potable urban reuses. The health risk was estimated by using quantitative microbial risk assessment. Two-dimensional Monte Carlo simulations were used in the analysis to include variability and uncertainty in input data. The proposed recommended values are based on the indicator organism E. coli. The required treatment levels for reuse were also estimated. In addition, the recommended values were successfully applied to three wastewater treatment effluents in the Okanagan Valley, BC, Canada. The health risks associated with other bacterial pathogens (Campylobacter jejuni and Salmonella spp.), virus (adenovirus, norovirus, and rotavirus), and protozoa (Cryptosporidium parvum and Giardia spp.), were also estimated. The estimated risks indicate the effectiveness of the E. coli-based water quality recommended values. Sensitivity analysis shows the pathogenic E. coli ratio and morbidity are the most sensitive input parameters for all water reuses. The proposed recommended values could be further improved by using national or regional data on water exposures, disease burden per case, and the susceptibility fraction of population.
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Affiliation(s)
- Gyan Chhipi-Shrestha
- School of Engineering, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna, BC V1V 1V7, Canada.
| | - Kasun Hewage
- School of Engineering, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna, BC V1V 1V7, Canada
| | - Rehan Sadiq
- School of Engineering, University of British Columbia, Okanagan Campus, 3333 University Way, Kelowna, BC V1V 1V7, Canada
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Abstract
Acute gastroenteritis (AGE) is one of the most common diseases of humans in both developed and developing countries. Despite the improved safety of food handling and prevention strategies, it remains one of the most significant health burdens on society1. An estimated 1.8 million AGE-associated deaths occur annually worldwide2,3, making it the leading cause of mortality among children under the age of five years. In this article, we examine recent trends in emerging noroviruses, the ability of the virus to cause outbreaks on cruise ships and discuss the factors that influence its on-board spread.
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49
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Tyson GH, Tate HP, Abbott J, Tran TT, Kabera C, Crarey E, Young S, McDermott PF, Sprague G, Campbell M, Adeyemo O, Browne-Silva J, Myers M, Thitaram S, Zhao S. Molecular Subtyping and Source Attribution of Campylobacter Isolated from Food Animals. J Food Prot 2016; 79:1891-1897. [PMID: 28221911 DOI: 10.4315/0362-028x.jfp-16-195] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Campylobacter spp. commonly cause gastrointestinal illness in humans. Poultry meats have long been considered the predominant source of these infections, but few in-depth Campylobacter source attribution studies have been completed. We analyzed more than 1,300 Campylobacter isolates recovered from a number of animal and food sources, including dairy and beef cattle, pigs, poultry, and retail poultry meat, and compared them with Campylobacter isolates recovered from human clinical samples. Each isolate was subtyped using pulsed-field gel electrophoresis (PFGE) with SmaI and queried against the Centers for Disease Control and Prevention PulseNet database to identify human isolates with indistinguishable patterns. Half (49.5%) of the PFGE patterns from poultry animal and retail meat isolates were indistinguishable from patterns of at least one human isolate. Among the isolates from beef and dairy cows, 56.6 and 65.0%, respectively, of their PFGE patterns were indistinguishable from those of human isolates. Only a small portion of the PFGE patterns of Campylobacter isolated from pigs (9.5%) were found to have PFGE patterns in common with human isolates. These data imply that cattle may be larger contributors to Campylobacter infections than previously recognized and help further our understanding of potential sources of human campylobacteriosis.
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Affiliation(s)
- Gregory H Tyson
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Heather P Tate
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Jason Abbott
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Thu-Thuy Tran
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Claudine Kabera
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Emily Crarey
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Shenia Young
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Patrick F McDermott
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
| | - Grisselle Sprague
- U.S. Department of Agriculture, Food Safety and Inspection Service, 950 College Station Road, Athens, Georgia 30601, USA
| | - Mark Campbell
- U.S. Department of Agriculture, Food Safety and Inspection Service, 950 College Station Road, Athens, Georgia 30601, USA
| | - Oyewole Adeyemo
- U.S. Department of Agriculture, Food Safety and Inspection Service, 950 College Station Road, Athens, Georgia 30601, USA
| | - Johnette Browne-Silva
- U.S. Department of Agriculture, Food Safety and Inspection Service, 950 College Station Road, Athens, Georgia 30601, USA
| | - Michael Myers
- U.S. Department of Agriculture, Food Safety and Inspection Service, 950 College Station Road, Athens, Georgia 30601, USA
| | - Sutawee Thitaram
- U.S. Department of Agriculture, Food Safety and Inspection Service, 950 College Station Road, Athens, Georgia 30601, USA
| | - Shaohua Zhao
- U.S. Food and Drug Administration, Center for Veterinary Medicine, 8401 Muirkirk Road, Laurel, Maryland 20708
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50
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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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