Disinfection of Viral Indicators and Treatability Implications for WRRFs

2018 ◽  
Vol 2018 (11) ◽  
pp. 3535-3539
Author(s):  
Thomas Worley-Morse ◽  
Melanie Mann ◽  
Wendell Khunjar ◽  
Raul Gonzalez
Keyword(s):  
Viral Indicators

A Comparison of Hand Washing Techniques To Remove Escherichia coli and Caliciviruses under Natural or Artificial Fingernails

2003 ◽  
Vol 66 (12) ◽  
pp. 2296-2301 ◽  
Author(s):  
CHIA-MIN LIN ◽  
FONE-MAO WU ◽  
HOI-KYUNG KIM ◽  
MICHAEL P. DOYLE ◽  
BARRY S. MICHAELS ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Tap Water ◽  
Hand Washing ◽  
Microbial Populations ◽  
Liquid Soap ◽  
E Coli ◽  
Hand Sanitizer ◽  
Before And After ◽  
Escherichia Coli Jm109 ◽  
Viral Indicators

Compared with other parts of the hand, the area beneath fingernails harbors the most microorganisms and is most difficult to clean. Artificial fingernails, which are usually long and polished, reportedly harbor higher microbial populations than natural nails. Hence, the efficacy of different hand washing methods for removing microbes from natural and artificial fingernails was evaluated. Strains of nonpathogenic Escherichia coli JM109 and feline calicivirus (FCV) strain F9 were used as bacterial and viral indicators, respectively. Volunteers with artificial or natural nails were artificially contaminated with ground beef containing E. coli JM109 or artificial feces containing FCV. Volunteers washed their hands with tap water, regular liquid soap, antibacterial liquid soap, alcohol-based hand sanitizer gel, regular liquid soap followed by alcohol gel, or regular liquid soap plus a nailbrush. The greatest reduction of inoculated microbial populations was obtained by washing with liquid soap plus a nailbrush, and the least reduction was obtained by rubbing hands with alcohol gel. Lower but not significantly different (P > 0.05) reductions of E. coli and FCV counts were obtained from beneath artificial than from natural fingernails. However, significantly (P ≤ 0.05) higher E. coli and FCV counts were recovered from hands with artificial nails than from natural nails before and after hand washing. In addition, microbial cell numbers were correlated with fingernail length, with greater numbers beneath fingernails with longer nails. These results indicate that best practices for fingernail sanitation of food handlers are to maintain short fingernails and scrub fingernails with soap and a nailbrush when washing hands.

Occurrence and persistence of bacterial and viral faecal indicators in wastewater biofilms

2007 ◽  
Vol 55 (8-9) ◽  
pp. 377-385 ◽  
Author(s):  
S. Skraber ◽  
K. Helmi ◽  
R. Willame ◽  
M. Ferréol ◽  
C. Gantzer ◽  
...  
Keyword(s):  
Dynamic Equilibrium ◽  
Wastewater Treatment Plants ◽  
Plate Count ◽  
Cryptosporidium Oocysts ◽  
The Matrix ◽  
Thermotolerant Coliforms ◽  
Viral Indicators ◽  
The Stability ◽  
Faecal Indicators ◽  
Giardia Cysts

Biofilms within wastewater treatment plants can capture enteric microorganisms initially present in the water phase immobilising them either definitively or temporarily. Consequently, fates of microorganisms may totally change depending on whether they interact or not with biofilms. In this study, we assessed the stability of wastewater biofilms comparing the evolution of the concentrations of bacteria (heterotrophic plate count [HPC], thermotolerant coliforms [TC]) and viral (somatic coliphages [SC] and F-specific phages [F+]) indicators in the biofilms and in the corresponding wastewaters at 4 and 20 °C. Additionally, we assessed the monthly occurrence of these bacterial and viral indicators as well as of pathogenic protozoa (Cryptosporidium oocysts and Giardia cysts) in three native wastewater biofilms for four months. Our results show that viral indicators (SC and F+) persist longer in biofilms than in the corresponding wastewaters at 4 °C as well as at 20 °C. In contrast, persistence of bacterial indicators (TC and HPC) depends on both the temperature and the matrix. Differences between viral and bacterial persistence are discussed. Monthly analysis of native wastewater biofilms shows that bacterial and viral indicators, as well as Cryptosporidium oocysts and Giardia cysts, attach to wastewater biofilms to a concentration that remains stable in time, probably as a result of a dynamic equilibrium between attachment and detachment processes.

scholarly journals Testing for viral material in water of public bathing areas of the Danube during summer, Vojvodina, Serbia, 2014

2016 ◽  
Vol 21 (15) ◽  
Author(s):  
Aleksandra Jovanović Galović ◽  
Sanja Bijelović ◽  
Vesna Milošević ◽  
Ivana Hrnjaković Cvjetkovic ◽  
Milka Popović ◽  
...  
Keyword(s):  
Surface Waters ◽  
Water Samples ◽  
Genetic Material ◽  
Recreational Water ◽  
Recreational Waters ◽  
Quality Of Water ◽  
Viral Indicators ◽  
Urban Wastewater Treatment ◽  
Recreational Use

From August to September 2014 a water quality study was conducted on five popular public Danube beaches in Vojvodina, Serbia. To assess the safety of Danube water for bathing, physical, chemical, bacteriological tests were performed. While many parameters for monitoring the quality of water are regulated by law, there are neither national nor international legislations addressing the presence of viruses in recreational waters. In this study, we performed analyses that surpassed national requirements, and investigated if adenovirus, enterovirus or rotavirus genetic material was present in samples of recreational water collected for quality monitoring. Of 90 water samples obtained during the study, enterovirus material was not found in any sample, but adenovirus and rotavirus genetic materials were respectively detected in 60 and 31 samples. Statistical analyses showed a significant correlation between adenovirus DNA and total coliforms in the water. Even when water samples were adequate for recreational use, adenoviruses were detected in 75% (57/76) of such samples. Our results indicate that implementation of viral indicators in recreational water might be helpful to better assess public health safety. This might be particularly relevant in areas where urban wastewater treatment is insufficient and surface waters affected by wastewater are used for recreation.

scholarly journals Human viruses and viral indicators in marine water at two recreational beaches in Southern California, USA

2013 ◽  
Vol 12 (1) ◽  
pp. 136-150 ◽  
Author(s):  
David C. Love ◽  
Roberto A. Rodriguez ◽  
Christopher D. Gibbons ◽  
John F. Griffith ◽  
Qilu Yu ◽  
...  
Keyword(s):  
Southern California ◽  
Enteric Viruses ◽  
Water Quality Monitoring ◽  
Fecal Coliforms ◽  
Detection Methods ◽  
Potential Health ◽  
Human Virus ◽  
Recreational Beaches ◽  
Viral Indicators ◽  
Human Viruses

Waterborne enteric viruses may pose disease risks to bather health but occurrence of these viruses has been difficult to characterize at recreational beaches. The aim of this study was to evaluate water for human virus occurrence at two Southern California recreational beaches with a history of beach closures. Human enteric viruses (adenovirus and norovirus) and viral indicators (F+ and somatic coliphages) were measured in water samples over a 4-month period from Avalon Beach, Catalina Island (n = 324) and Doheny Beach, Orange County (n = 112). Human viruses were concentrated from 40 L samples and detected by nested reverse transcriptase polymerase chain reaction (PCR). Detection frequencies at Doheny Beach were 25.5% (adenovirus) and 22.3% (norovirus), and at Avalon Beach were 9.3% (adenovirus) and 0.7% (norovirus). Positive associations between adenoviruses and fecal coliforms were observed at Doheny (p = 0.02) and Avalon (p = 0.01) Beaches. Human viruses were present at both beaches at higher frequencies than previously detected in the region, suggesting that the virus detection methods presented here may better measure potential health risks to bathers. These virus recovery, concentration, and molecular detection methods are advancing practices so that analysis of enteric viruses can become more effective and routine for recreational water quality monitoring.

DEVELOPMENT OF A SPOT-TITER CULTURE ASSAY FOR QUANTIFYING BACTERIA AND VIRAL INDICATORS

2009 ◽  
Vol 17 (4) ◽  
pp. 455-464 ◽  
Author(s):  
N.K. BECK ◽  
K. CALLAHAN ◽  
S.P. NAPPIER ◽  
H. KIM ◽  
M.D. SOBSEY ◽  
...  
Keyword(s):  
Viral Indicators

scholarly journals Evaluation of F-Specific RNA Bacteriophage as a Candidate Human Enteric Virus Indicator for Bivalve Molluscan Shellfish

2000 ◽  
Vol 66 (4) ◽  
pp. 1280-1285 ◽  
Author(s):  
William J. Doré ◽  
Kathleen Henshilwood ◽  
David N. Lees
Keyword(s):  
Disease Outbreaks ◽  
Enteric Virus ◽  
Seasonal Trend ◽  
Human Consumption ◽  
Point Of Sale ◽  
E Coli ◽  
Reverse Transcription Pcr ◽  
The United Kingdom ◽  
Viral Indicators ◽  
A Site

ABSTRACT Escherichia coli is a widely utilized indicator of the sanitary quality of bivalve molluscan shellfish sold for human consumption. However, it is now well documented that shellfish that meet the E. coli standards for human consumption may contain human enteric viruses that cause gastroenteritis and hepatitis. In this study we investigated using F-specific RNA bacteriophage (FRNA bacteriophage) to indicate the likely presence of such viruses in shellfish sold for consumption. FRNA bacteriophage and E. coli levels were determined over a 2-year period for oysters (Crassostrea gigas) harvested from four commercial sites chosen to represent various degrees of sewage pollution. Three sites were classified as category B sites under the relevant European Community (EC) Directive (91/492), which required purification (depuration) of oysters from these sites before sale. One site was classified as a category A site, and oysters from this site could be sold directly without further processing. Samples were tested at the point of sale following commercial processing and packaging. All of the shellfish complied with the mandatory EC E. coli standard (less than 230 per 100 g of shellfish flesh), and the levels of contamination for more than 90% of the shellfish were at or below the level of sensitivity of the assay (20 E. coli MPN per 100 g), which indicated good quality based on this criterion. In contrast, FRNA bacteriophage were frequently detected at levels that exceeded 1,000 PFU per 100 g. High levels of FRNA bacteriophage contamination were strongly associated with harvest area fecal pollution and with shellfish-associated disease outbreaks. Interestingly, FRNA bacteriophage contamination exhibited a marked seasonal trend that was consistent with the trend of oyster-associated gastroenteritis in the United Kingdom. The correlation between FRNA bacteriophage contamination and health risk was investigated further by using a reverse transcription-PCR assay for Norwalk-like virus (NLV). NLV contamination of oysters was detected only at the most polluted site and also exhibited a seasonal trend that was consistent with the trend of FRNA bacteriophage contamination and with the incidence of disease. The results of this study suggest that FRNA bacteriophage could be used as viral indicators for market-ready oysters.

scholarly journals Unsafe tap water in households supplied from groundwater in the Salento Region of Southern Italy

2006 ◽  
Vol 5 (1) ◽  
pp. 129-148 ◽  
Author(s):  
Costantino Masciopinto ◽  
Rosanna La Mantia ◽  
Annalaura Carducci ◽  
Beatrice Casini ◽  
Agata Calvario ◽  
...  
Keyword(s):  
Southern Italy ◽  
Transport Model ◽  
Tap Water ◽  
Local Population ◽  
Epidemiological Data ◽  
Fractured Aquifer ◽  
Somatic Coliphages ◽  
Complete Inactivation ◽  
Groundwater Samples ◽  
Viral Indicators

Although the fractured aquifer of the Salento supplies over 80% of the drinking water requirements of the local population, its exposure to pollution has recently increased. In recent years, owing to the arid climate and droughts, the spreading of wastewater on soil for irrigation has become much more frequent. Consequently, hazardous and pathogenic microorganisms released with wastewater have been transported into the subsoil and have contaminated groundwater. An elaboration of epidemiological data has shown that the local population has the highest exposure to endemic gastroenteritis in Italy. In order to reduce human exposure to unsafe groundwater, the setback distance for drinking wells necessary to achieve the ‘natural disinfectionߣ criteria, has been determined experimentally at the Nardò aquifer (Salento region), supported by groundwater monitoring results and a mathematical transport model able to determine the apparent pathogenic microorganism pathways in fractures. The results also provided valuable inactivation constants of cultural indicators (coliforms, enterococci, Clostridium spores and somatic coliphages) and viruses in the wastewater that have been injected into the fractured aquifer since 1991. Furthermore, the efficacy of chlorine to remove viral indicators from water in a well 500 m from wastewater injection was tested. Hypochlorination reduces somatic coliphages and Clostridium spores in groundwaters but did not achieve complete inactivation in all tests. Complete disinfection of groundwater samples was possible only when there was an initial Clostridium spores count of ≤10 CFU 100 ml-1.

Removal of fecal coliforms, somatic coliphages and F-specific bacteriophages in a stabilization pond and reservoir system in arid regions

2003 ◽  
Vol 3 (4) ◽  
pp. 177-184 ◽  
Author(s):  
L. Alcalde ◽  
G. Oron ◽  
L. Gillerman ◽  
M. Salgot ◽  
Y. Manor
Keyword(s):  
Treatment System ◽  
Fecal Coliforms ◽  
Somatic Coliphages ◽  
Stabilization Pond ◽  
Reservoir System ◽  
Viral Indicators ◽  
One Year ◽  
Physical And Chemical ◽  
The City

The contents of FC, somatic coliphages and F-specific bacteriophages were measured in the stabilization pond and stabilization reservoir system of the City of Arad (Israel) in order to determine the efficiency of the treatment process regarding the microorganisms removal. Monitoring was conducted close to one year. Physical and chemical parameters (temperature, pH, BOD5, COD, SS) were also analyzed with the aim of finding factors that affect the microorganisms removal. The field results prove a very good performance of this treatment system. FC, somatic coliphages and F-specific bacteriophages were removed between 4.16 and 5.76 log units, during winter and in between 6.02 and 6.47 log units during summer. The microbial quality of the final effluent complies with the WHO guidelines for unrestricted irrigation. The results also indicate that retention time and temperature seem to be the most important factors for microorganisms removal. F-specific bacteriophages were removed at higher rates than FC and somatic coliphages. Consequently, it is suggested that F-specific bacteriophages might be less adequate viral indicators for this treatment system.

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