scholarly journals The challenge of SARS-CoV-2 environmental monitoring in schools using floors and portable HEPA filtration units: Fresh or relic RNA?

2021 ◽  
Author(s):  
Rogelio Zuniga-Montanez ◽  
David A Coil ◽  
Jonathan A Eisen ◽  
Randi Pechacek ◽  
Roque G Guerrero ◽  
...  
Keyword(s):  
Environmental Samples ◽  
High Efficiency ◽  
Monitoring Program ◽  
Environmental Sampling ◽  
Sampling Strategies ◽  
Clinical Testing ◽  
Interior Spaces ◽  
Single Room ◽  
Public Health Information ◽  
Positive Results

Testing surfaces in school classrooms for the presence of SARS-CoV-2, the virus that causes COVID-19, can provide public-health information that complements clinical testing. We monitored the presence of SARS-CoV-2 RNA in five schools (96 classrooms) in Davis, California (USA) by collecting weekly surface-swab samples from classroom floors and/or portable high-efficiency particulate air (HEPA) units. Twenty-two surfaces tested positive, with qPCR cycle threshold (Ct) values ranging from 36.07-38.01. Intermittent repeated positives in a single room were observed for both floor and HEPA filter samples for up to 52 days , even following regular cleaning and HEPA filter replacement after a positive result. We compared the two environmental sampling strategies by testing one floor and two HEPA filter samples in 57 classrooms at Schools D and E. HEPA filter sampling yielded 3.02% and 0.41% positivity rates per filter sample collected for Schools D and E, respectively, while floor sampling yielded 0.48% and 0% positivity rates. Our results indicate that HEPA filter swabs are more sensitive than floor swabs at detecting SARS-CoV-2 RNA in interior spaces. During the study, all schools were offered weekly free COVID-19 clinical testing. On-site clinical testing was offered in Schools D and E, and upticks in testing participation were observed following a confirmed positive environmental sample. However, no confirmed COVID-19 cases were identified among students associated with classrooms yielding positive environmental samples. The positive samples detected in this study appeared to reflect relic viral RNA from individuals infected before the monitoring program started and/or RNA transported into classrooms via fomites. The high-Ct positive results from environmental swabs further suggest the absence of active infections. Additional research is needed to differentiate between fresh and relic SARS-CoV-2 RNA in environmental samples and to determine what types of results should trigger interventions.

Enhanced Detection of Listeria spp. in Farmstead Cheese Processing Environments through Dual Primary Enrichment, PCR, and Molecular Subtyping

2008 ◽  
Vol 71 (11) ◽  
pp. 2239-2248 ◽  
Author(s):  
DENNIS J. D'AMICO ◽  
CATHERINE W. DONNELLY
Keyword(s):  
Listeria Monocytogenes ◽  
Environmental Samples ◽  
Environmental Sampling ◽  
Strain Diversity ◽  
Enrichment Protocol ◽  
Automated Ribotyping ◽  
Epidemiological Significance ◽  
Enrichment Methods ◽  
Over Time ◽  
Higher Sensitivity

The incidence and ecology of Listeria spp. in farmstead cheese processing environments were assessed through environmental sampling conducted in nine different plants over a 10-week period. Environmental samples (n = 705) were examined for the presence of Listeria spp. by using three detection/isolation protocols. The use of dual enrichment methods, which allowed for the recovery of injured Listeria spp. (mUSDA), identified more Listeria species–positive samples with higher sensitivity than the standard USDA method. The addition of PCR to the mUSDA method identified the most Listeria monocytogenes–positive samples, achieving greater sensitivity of detection while substantially reducing time. Overall, 7.5% of samples were positive for Listeria spp., yielding 710 isolates, 253 of which were subtyped by automated ribotyping to examine strain diversity within and between plants over time. The isolation of specific ribotypes did not appear to be affected by the enrichment protocol used. Fifteen (2.1%) samples yielded L. monocytogenes isolates differentiated almost equally into ribotypes of lineages I and II. Of most concern was the persistent and widespread contamination of a plant with L. monocytogenes DUP-1042B, a ribotype previously associated with multiple outbreaks of listeriosis. Our results suggest that the extent of contamination by Listeria spp., notably L. monocytogenes, in farmstead cheese plants is comparatively low, especially for those with on-site farms. The results of this study also identified points of control for use in designing more effective Listeria spp. control and monitoring programs with a focus on ribotypes of epidemiological significance.

scholarly journals Comparison of Four Polymerase Chain Reaction Methods for the Rapid Detection of Human Fecal Pollution in Marine and Inland Waters

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Dave S. Bachoon ◽  
Cortney M. Miller ◽  
Christen P. Green ◽  
Ernesto Otero
Keyword(s):  
Puerto Rico ◽  
Environmental Samples ◽  
Fecal Pollution ◽  
Chain Reaction ◽  
Bifidobacterium Adolescentis ◽  
Fecal Samples ◽  
Pcr Method ◽  
Polymerase Chain ◽  
Positive Results ◽  
Human Specific

We compared the effectiveness of three PCR protocols for the detection ofBifidobacterium adolescentisand one PCR protocol for detectingBacteroidalesas indicators of human fecal pollution in environmental samples. Quantitative PCR indicated that a higher concentration ofB. adolescentisDNA was recovered from sewage samples on the 0.2 μm filters compared to the 0.45 μm filters, and there was no evidence of qPCR inhibitors in the DNA extracts. With the Matsuki method (1999),B. adolescentiswas detected only in undiluted sewage samples. The King method (2007) performed well and detectedB. adolescentisin all of the sewage dilutions (from undiluted to10−4). In contrast, the Bonjoch approach (2004) was effective at detectingB. adolescentisat lower dilutions (10−3) of sewage samples and it gave false positive results with some (3/8) pig fecal samples. Human-specificBacteroidales(HuBacs) were detected in the lower diluents of sewage samples but was positive in pig (6/8) and cattle fecal samples. PCR detection ofB. adolescentisin marine samples from Puerto Rico and freshwater samples from Georgia indicated that the PCR method of King et al. (2007) and the modified Layton method for HuBac were in agreement in detecting human fecal pollution in most sites.

scholarly journals SARS-CoV-2 and Environmental Samples: A Methodological Approach to Have Consistent and Comparable Results

2020 ◽  
Author(s):  
Angelo Robotto ◽  
Paola Quaglino ◽  
David Lembo ◽  
Marcello Morello ◽  
Enrico Brizio ◽  
...  
Keyword(s):  
Environmental Samples ◽  
Methodological Approach ◽  
Sampling Technique ◽  
Complete Information ◽  
Environmental Sampling ◽  
Air Samples ◽  
Order Of Magnitude ◽  
Wastewater Samples ◽  
The Relationship ◽  
Parallel Sampling

Since the beginning of coronavirus disease 2019 (COVID-19) pandemic, large attention has been focused on the relationship between SARS-CoV-2 diffusion and environment. As a matter of fact, clear evidence of the transmission of SARS-CoV-2 via respiratory aerosol would be of primary importance; at the same time, checking the presence of SARS-CoV-2 in wastewater can be extremely useful to control the diffusion of the disease. Up to now, many studies report SARS-CoV-2 concentrations in indoor/outdoor air samples or water/wastewater samples that can differ by order of magnitude. Unfortunately, complete information about the scientific approach of many studies is still missing, relating to: samplers and sampling materials performances, recovery tests, measurement uncertainty, robustness, detection and quantification limits, infectivity of captured virus, virus degradation during sampling, influence of sample pre-treatments (included freezing) on results, effects of inhibitors, sample alterations due to manipulation, validation of methods and processes, quality assurance according to ISO/IEC 17025 requirements.Based on the first experiences focused on the presence of SARS-CoV-2 in environmental samples such as air quality filters, air-liquid impingers and wastewater samples, the present study describes a coherent preliminary approach to SARS-CoV-2 environmental sampling in order to overcome the evident lack of standardization. Three aspects are highlighted here: the first solution to assure quality and consistency to environmental sampling relies on the development of recovery tests using standard materials and investigating sampling materials, sampling techniques, sampling durations, sample conservation and pre-treatments; secondly, in order to overcome the shortcomings of every single sampling technique, coupling different samplers in parallel sampling could be an efficient strategy to collect more information and make data more reliable, in particular for air samples; finally, with regards to airborne virus sampling, the results could be confirmed by simplified emission and dilution models.

scholarly journals Experimental investigation of Microcystis aeruginosa cyanobacteria thickening to obtain a biomass for the energy production

2019 ◽  
Vol 43 (1) ◽  
pp. 113-119
Author(s):  
Myroslav Malovanyy ◽  
Volodymyr Zhuk ◽  
Volodymyr Nykyforov ◽  
Igor Bordun ◽  
Iurii Balandiukh ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
High Efficiency ◽  
Hydrodynamic Cavitation ◽  
Concentrated Suspensions ◽  
Energy Carriers ◽  
Maximum Extraction ◽  
Negative Effect ◽  
Gravity Thickening ◽  
Positive Results ◽  
Potential Efficiency

AbstractThe purpose of the presented research is to analyse possible methods of thickening of the Microcystis aeruginosa (Kützing) Kützing cyanobacteria using the obtained concentrate as a biomass for the production of energy carriers and biologically valuable substances. Method of cyanobacteria thickening under the action of electric current and in the electric field, as well as the method of coagulation–flocculation and gravity thickening, was experimentally investigated in labscale conditions. Electrical methods didn't show positive results for the Microcystis aeruginosa thickening, despite the reports of their potential efficiency in a number of previous studies. The high efficiency of the method of coagulation– flocculation and gravity thickening of Microcystis aeruginosa suspensions was obtained. The optimum concentrations of industrial polymeric coagulants and flocculants for the thickening of Microcystis aeruginosa suspensions were defined in the range of about 10 ppm for the coagulants and about 1 ppm for the flocculants. Negative effect of the previous cavitational treatment of the diluted suspensions of Microcystis aeruginosa on the effectiveness of the coagulation–flocculation and gravitational thickening was confirmed experimentally. Hydrodynamic cavitation should be recommended to use after the thickening as the next step of processing of concentrated suspensions of Microcystis aeruginosa to achieve maximum extraction of energy carriers and biologically valuable substances.

scholarly journals Reveal®Salmonella 2.0 Test for Detection of Salmonella spp. in Foods and Environmental Samples

2011 ◽  
Vol 94 (5) ◽  
pp. 1467-1480
Author(s):  
Rebecca Hoerner ◽  
Jill Feldpausch ◽  
R Lucas Gray ◽  
Stephanie Curry ◽  
Zahidul Islam ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Irrigation Water ◽  
Environmental Samples ◽  
Steel Surface ◽  
Reference Method ◽  
Stainless Steel Surface ◽  
Salmonella Spp ◽  
Culture Methods ◽  
Chi Square Analysis ◽  
Positive Results

Abstract Reveal Salmonella 2.0 is an improved version of the original Reveal Salmonella lateral flow immunoassay and is applicable to the detection of Salmonella enterica serogroups A–E in a variety of food and environmental samples. A Performance Tested MethodSM validation study was conducted to compare performance of the Reveal 2.0 method with that of the U.S. Department of Agriculture-Food Safety and Inspection Service or U.S. Food and Drug Administration/Bacteriological Analytical Manual reference culture methods for detection of Salmonella spp. in chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, raw shrimp, a ready-to-eat meal product, dry pet food, ice cream, spinach, cantaloupe, peanut butter, stainless steel surface, and sprout irrigation water. In a total of 17 trials performed internally and four trials performed in an independent laboratory, there were no statistically significant differences in performance of the Reveal 2.0 and reference culture procedures as determined by Chi-square analysis, with the exception of one trial with stainless steel surface and one trial with sprout irrigation water where there were significantly more positive results by the Reveal 2.0 method. Considering all data generated in testing food samples using enrichment procedures specifically designed for the Reveal method, overall sensitivity of the Reveal method relative to the reference culture methods was 99%. In testing environmental samples, sensitivity of the Reveal method relative to the reference culture method was 164%. For select foods, use of the Reveal test in conjunction with reference method enrichment resulted in overall sensitivity of 92%. There were no unconfirmed positive results on uninoculated control samples in any trials for specificity of 100%. In inclusivity testing, 102 different Salmonella serovars belonging to serogroups A–E were tested and 99 were consistently positive in the Reveal test. In exclusivity testing of 33 strains of non-salmonellae representing 14 genera, 32 were negative when tested with Reveal following nonselective enrichment, and the remaining strain was found to be substantially inhibited by the enrichment media used with the Reveal method. Results of ruggedness testing showed that the Reveal test produces accurate results even with substantial deviation in sample volume or device development time.

Anticipative monitoring to improve chemotherapy induced nausea.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 10120-10120
Author(s):  
Reza Elaidi ◽  
Stephane Oudard ◽  
Hail Aboudagga ◽  
Constance Thibault ◽  
Lorraine Waechter ◽  
...  
Keyword(s):  
Monitoring Program ◽  
Primary Objective ◽  
P Values ◽  
Anti Cancer ◽  
Patient Waiting Time ◽  
Secondary Objective ◽  
Grade 3 ◽  
Improving Patient Care ◽  
Positive Results

10120 Background: The PROCHE [Programme for optimisation of the chemotherapy network] initiative is an innovative oncology-monitoring program designed to reduce patient waiting time and chemotherapy wastage, ultimately improving patient care. Methods: Primary objective was to evaluate the incidence of nausea reported by grade (NCI-CTC AE: from 0 to 4) from 2008 to 2016. Association was quantified using Mantel-Haenszel khi2 and exact p-values. Secondary objective compared the 2009-2016 patients with the control patients of 2008 period. Results: Between Oct 2008 and Oct 2016, 3012 patients participated in the program, representing 36 803 questionnaires completed over the whole period. Nausea was, clinically and statistically, significantly improved during the whole follow-up period with a decrease of grade 3-4 from 0.6% to 0.08% and a decrease of grade 1-2 from 29.3% to 8.2%. The already adapted nausea management in 2008 with 70% of questionnaires reported no nausea improved to 92% in 2016, with a 10% improvement the year after program initiation. As MASCC propose to change guidelines with an improvement above 10%, such an organization may impact new recommendations. Conclusions: Anticipating anti-cancer treatment adaptation and prevention, following guidelines and using adapted antiemetics, explain these positive results. The PROCHE initiative improves chemotherapy induced nausea. [Table: see text]

scholarly journals Microbiological contamination in three large-scale pig slaughterhouses in Northern Italy

2016 ◽  
Vol 5 (4) ◽  
Author(s):  
Pierluigi Di Ciccio ◽  
Maria Cristina Ossiprandi ◽  
Emanuela Zanardi ◽  
Sergio Ghidini ◽  
Giancarlo Belluzzi ◽  
...  
Keyword(s):  
Environmental Samples ◽  
Large Scale ◽  
Viable Count ◽  
Northern Italy ◽  
Environmental Sampling ◽  
Total Viable Count ◽  
Microbiological Contamination ◽  
Line Speed ◽  
Pig Carcasses ◽  
Carcass Contamination

The aim of this survey was to obtain data on microbiological contamination of pig carcasses and environments in three large-scale Italian slaughterhouses (identified as A-B-C) located in Northern Italy. Each slaughterhouse was visited six times. Five carcasses and three different sites of the slaughterhouse (before and during slaughter) were sampled on each sampling day. A single pooled caecal sample was taken on each sampling day. A total of 90 carcasses, 108 environmental samples and 18 caecal samples were collected. Samples from pig carcasses and slaughterhouse environment were analyzed for Total Viable Count (TVC), <em>Enterobacteriaceae</em> count (EBC) and <em>Salmonella</em>. The caecal contents were examined for Salmonella. Carcasses from slaughterhouse A presented the greatest TVC and EBC mean log value, whereas environmental samples collected during slaughter activities from slaughterhouse C showed the greatest TVC and EBC mean log value. As far as the environmental samples collected before slaughter activities are concerned, an average up to 6 log10 CFU/cm2 TVC in two slaughter plants (A and C) and 5 log10 CFU/cm2 TVC in one slaughter plant (B) was detected. <em>Salmonella</em> was recovered in two slaughterhouses (A and B). Four different <em>Salmonella</em> serotypes were detected in the positive samples (11). Within serotype <em>S. Rissen</em> and <em>S. Typhimurium</em> monophasic-variant isolates, two PFGE patterns were identified. The findings in this survey suggest that carcass contamination is influenced by the slaughterhouse plant and this could be a result of differences in line speed. The results of environmental sampling have not shown an association with the slaughterhouse plant.

Validation of the ANSR™ Salmonella Method for Detection of Salmonella spp. in Selected Foods and Environmental Samples

2013 ◽  
Vol 96 (4) ◽  
pp. 842-853 ◽  
Author(s):  
Mark Mozola ◽  
Paul Norton ◽  
Susan Alles ◽  
R Lucas Gray ◽  
Jerry Tolan ◽  
...  
Keyword(s):  
Drug Administration ◽  
Environmental Samples ◽  
Food And Drug Administration ◽  
Molecular Diagnostic ◽  
Stainless Steel Surface ◽  
Sample Type ◽  
Salmonella Spp ◽  
Nucleic Acid Amplification Technology ◽  
Positive Results ◽  
The U.S

Abstract ANSR™ Salmonella is a new molecular diagnostic assay for detection of Salmonella spp. in foods and environmental samples. The test is based on the nicking enzyme amplification reaction (NEAR™) isothermal nucleic acid amplification technology. The assay platform features simple instrumentation, minimal labor, and, following a single-step 10–24 h enrichment (depending on sample type), an extremely short assay time of 30 min, including sample preparation. Detection is real-time using fluorescent molecular beacon probes. Inclusivity testing was performed using a panel of 113 strains of S. enterica and S. bongori, representing 109 serovars and all genetic subgroups. With the single exception of the rare serovar S. Weslaco, all serovars and genetic subgroups were detected. Exclusivity testing of 38 nonsalmonellae, mostly Enterobacteriaceae, yielded no evidence of cross-reactivity. In comparative testing of chicken carcass rinse, raw ground turkey, raw ground beef, hot dogs, and oat cereal, there were no statistically significant differences in the number of positive results obtained with the ANSR and the U.S. Department of Agriculture-Food Safety and Inspection Service or U.S. Food and Drug Administration/Bacteriological Analytical Manual reference culture methods. In testing of swab or sponge samples from five different environmental surfaces, four trials showed no statistically significant differences in the number of positive results by the ANSR and the U.S. Food and Drug Administration/Bacteriological Analytical Manual reference methods; in the trial with stainless steel surface, there were significantly more positive results by the ANSR method. Ruggedness experiments showed a high degree of assay robustness when deviations in reagent volumes and incubation times were introduced.

Environmental Survey for Listeria Species in California Milk Processing Plants

1990 ◽  
Vol 53 (3) ◽  
pp. 198-201 ◽  
Author(s):  
BRUCE R. CHARLTON ◽  
HAILU KINDE ◽  
LEON H. JENSEN
Keyword(s):  
Listeria Monocytogenes ◽  
Environmental Samples ◽  
Raw Milk ◽  
Plant Location ◽  
Milk Product ◽  
Isolation Rate ◽  
Milk Processing ◽  
Processing Plants ◽  
Manufacturing Activity ◽  
Positive Results

This survey was undertaken to determine the prevalence of Listeria monocytogenes and Listeria spp. in environmental samples obtained from milk processing plants located throughout California. Identification of Listeria spp. other than L. monocytogenes was not made. Milk processing plants were categorized as to type of product produced and subdivided into areas based on manufacturing activity occurring in that area. A total of 597 environmental samples from 156 plants were analyzed in the six month period of January through July 1987. Listeria spp. were isolated from 75 (12.6%) of the samples. Thirty-eight of the Listeria spp. (50.7%) were identified as L. monocytogenes. Forty-six plants (29.5%) yielded positive results for Listeria spp., of which, 31 plants (19.9%) were positive for L. monocytogenes. Listeria was recovered more frequently from fluid milk product plants and frozen milk product plants. Likewise, Listeria was isolated most frequently from the packaging-filling room location within a plant and least frequently from the raw milk receiving room. Although Listeria spp. was isolated most frequently from the conveyor site, the drain site within a plant location gave a Listeria isolation rate similar to the total number of Listeria positive sites within that plant location.

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