Assessment of F-RNA Coliphage as a Potential Indicator of Enteric Virus Contamination of Hog Carcasses

2012 ◽  
Vol 75 (8) ◽  
pp. 1492-1500 ◽  
Author(s):  
T. H. JONES ◽  
M. W. JOHNS
Keyword(s):  
Nucleic Acid ◽  
Enteric Viruses ◽  
Enteric Virus ◽  
Hepatitis E ◽  
Molecular Techniques ◽  
Aerobic Bacteria ◽  
Meat Processing ◽  
Viral Nucleic Acid ◽  
E Coli ◽  
Low Levels

Hepatitis E virus (HEV) is common in pigs, and some swine HEV strains are closely related to human strains. The zoonotic transmission of HEV is now well established. HEV can be detected by molecular techniques, but the significance of the presence of viral nucleic acid is questionable when foods are subjected to virus inactivation treatments. F-RNA coliphages are attractive candidates as indicators for enteric viruses because they are similar in size and survival characteristics and can be rapidly cultured. Information on the contamination of hog carcasses with enteric or hepatic viruses during slaughter is lacking. The objective of this study was to compare the incidence and levels of contamination of hog carcasses with F-RNA coliphages, HEV, total aerobic bacteria, coliforms, and Escherichia coli at different stages of the dressing process. Hog carcasses entering the commercial slaughter facility are heavily contaminated with F-RNA coliphages and HEV. Subsequent processes such as scalding, singing, and pasteurization can reduce the incidence and levels of F-RNA coliphages and HEV substantially to almost undetectable levels. Large discrepancies between the amount of viral nucleic acid and infectious F-RNA coliphage particles, both at high levels and low levels of contamination, were observed. The prevalence and levels of viable F-RNA coliphages were lower than those of total aerobic bacteria, coliforms, and E. coli in the anal area and on random sites before pasteurization. At a research abattoir, there was no overall mean reduction of viable F-RNA coliphages recovered from random sites before pasteurization and after washing, whereas overall mean reductions of 1.2, 2.6, and 2.9 log CFU for total aerobic bacteria, coliforms, and E. coli, respectively, were obtained. These findings suggest that bacteria such as coliforms and E. coli may not be suitable as indicators for enteric viruses in a meat processing environment.

Bacteriophages and bacteria as indicators of enteric viruses in oysters and their harvest waters

1998 ◽  
Vol 38 (12) ◽  
pp. 37-44 ◽  
Author(s):  
H. Chung ◽  
L.-A. Jaykus ◽  
G. Lovelace ◽  
M. D. Sobsey
Keyword(s):  
Enteric Viruses ◽  
Enteric Virus ◽  
Indicator Bacteria ◽  
Faecal Coliforms ◽  
Rt Pcr ◽  
E Coli ◽  
Virus Contamination ◽  
Receiving Waters ◽  
Male Specific ◽  
Receiving Water

Reliable indicators are needed to detect enteric virus contamination of bivalve molluscan shellfish and their harvest waters. Concentrations of male-specific (F+) coliphages, Bacteroides fragilis phages, Salmonella phages and several indicator bacteria in wastewater, estuarine receiving water and its oysters were examined for their ability to predict the presence and levels of faecal contamination and enteric viruses in oysters. Enteric viruses in oysters were detected by cell culture and RT-PCR methods. F+ coliphages, Salmonella phages, B fragilis phages and faecal indicator bacteria (faecal coliforms, E coli, enterococci and Clostridium perfringens) were generally positively associated and were highest in raw sewage and progressively lower in sewage effluent and in receiving waters at increasing distance from the wastewater discharge. Indicator levels in oysters were highest for F+ coliphages and C perfringens. One F+ RNA coliphage serotype (Group II) predominated in the wastewater, receiving water and oysters. Human enteric viruses were detected in 17/31 oyster samples. The levels of most indicators in oysters and water were higher when oysters were enteric virus-positive and lower when oysters were enteric virus-negative. F+ coliphages and C perfringens were the only indicators significantly associated with the presence of enteric viruses in oysters. F+ coliphages and their serotypes are promising indicators of human enteric virus contamination in oysters and their harvest waters.

scholarly journals Specific bacterial cell wall components influence the stability of Coxsackievirus B3

2021 ◽  
Author(s):  
Adeeba H Dhalech ◽  
Tara D Fuller ◽  
Christopher M Robinson
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
Enteric Viruses ◽  
Enteric Virus ◽  
Coxsackievirus B3 ◽  
Gram Negative ◽  
Cell Wall Components ◽  
E Coli ◽  
Wall Components

Enteric viruses infect the mammalian gastrointestinal tract and lead to significant morbidity and mortality worldwide. Data indicate that enteric viruses can utilize intestinal bacteria to promote viral replication and pathogenesis. However, the precise interactions between enteric viruses and bacteria are unknown. Here we examined the interaction between bacteria and Coxsackievirus B3, an enteric virus from the picornavirus family. We found that bacteria enhance the infectivity of Coxsackievirus B3 (CVB3) in vitro. Notably, specific bacteria are required as gram-negative Salmonella enterica, but not Escherichia coli, enhanced CVB3 infectivity and stability. Investigating the cell wall components of both S. enterica and E. coli revealed that structures in the O-antigen or core of lipopolysaccharide, a major component of the gram-negative bacterial cell wall, were required for S. enterica to enhance CVB3. To determine if these requirements were necessary for similar enteric viruses, we investigated if S. enterica and E. coli enhanced infectivity of poliovirus, another enteric virus in the picornavirus family. We found that, in contrast to CVB3, these bacteria enhanced the infectivity of poliovirus in vitro. Overall, these data indicate that distinct bacteria enhance CVB3 infectivity and stability, and specific enteric viruses may have differing requirements for their interactions with specific bacterial species.

Sensitivity of Escherichia coli to Viral Nucleic Acid, XII. Ca2+-or Ba2+-Facilitated Transfection of Cell Envelope Mutants

1977 ◽  
Vol 32 (5-6) ◽  
pp. 429-433 ◽  
Author(s):  
Akira Taketo
Keyword(s):  
Escherichia Coli ◽  
Nucleic Acid ◽  
Outer Membrane ◽  
Cell Envelope ◽  
Nucleoside Transport ◽  
Wild Type ◽  
Viral Nucleic Acid ◽  
E Coli ◽  
The Relationship ◽  
Cellular Competence

Abstract Using various envelope mutants of Escherichia coli, the relationship between cell surface struc­ture and the Ca2+-or Ba2+-dependent competence for transfection was investigated. In contrast with rough strains, smooth bacteria treated with Ca2+ or Ba2+ were incompetent for the trans­fection by ØA RF. In E. coli K12 D21 derivatives, Ca2+-dependent competence remarkably in­ creased by lpsAl mutation and the highest level of competence was attained by further deficiency in glucose units of the LPS. Upon treatment with BaCl2 , strain D21 and its lpsAl mutant became highly competent for ØA RF. The effect of Ba2+ was, however, feeble for lpsAl mutants further deficient in heptose units and/or glucose units. Among different LPS mutants of E. coli B, variation of the Ca2+-or Ba2+-dependent competence was relatively small and even the competence of strain BB12, whose LPS core contained only two KDO units, was nearly equal to that of wild type bacteria. However, the level of cellular competence induced by Ba2+ was not allways parallel to that induced by Ca2+. In mutants deficient in outer membrane protein I, either Ca2+-or Ba2+-dependent competence increased several-fold, whereas in mutants devoid of outer membrane II*, the com­petence decreased considerably. Unlike nucleoside transport, the uptake of DNA was not affected by tsx mutation.

scholarly journals Enteric viruses in municipal wastewater effluent before and after disinfection with chlorine and ultraviolet light

2019 ◽  
Vol 17 (5) ◽  
pp. 670-682 ◽  
Author(s):  
Albert Simhon ◽  
Vince Pileggi ◽  
Cecily A. Flemming ◽  
José R. Bicudo ◽  
George Lai ◽  
...  
Keyword(s):  
Membrane Filtration ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Uv Light ◽  
Geometric Mean ◽  
Enteric Viruses ◽  
Enteric Virus ◽  
Wastewater Effluent ◽  
Uv Disinfection ◽  
E Coli

Abstract In Ontario, Canada, information is lacking on chlorine and ultraviolet (UV) light disinfection performance against enteric viruses in wastewater. We enumerated enteroviruses and noroviruses, coliphages, and Escherichia coli per USEPA methods 1615, 1602, and membrane filtration, respectively, in pre- and post-disinfection effluent at five wastewater treatment plants (WWTPs), with full-year monthly sampling, and calculated log10 reductions (LRs) while WWTPs complied with their monthly geometric mean limit of 200 E. coli/100 mL. Modeling of densities by left-censored estimation and Bayesian inference gave very similar results. Polymerase chain reaction (PCR)-detected enteroviruses and noroviruses were abundant in post-disinfection effluent (mean concentrations of 2.1 × 10+4–7.2 × 10+5 and 2.7 × 10+4–3.6 × 10+5 gene copies (GC)/L, respectively). Chlorine or UV disinfection produced modest LRs for culture- (0.3–0.9) and PCR-detected enteroviruses (0.3–1.3), as well as noroviruses GI + GII (0.5–0.8). Coliphages and E. coli were more susceptible, with LRs of 0.8–3.0 and 2.5, respectively. Sand-filtered effluent produced significantly higher enteric virus LRs (except cultured enteroviruses). Coliphage and human enteric virus densities gave significantly positive correlations using Kendall's Tau test. Enteric viruses are abundant in wastewater effluent following routine chlorine or UV disinfection processes that target E. coli. Coliphages appear to be good indicators for evaluating wastewater disinfection of enteric viruses.

scholarly journals Specific bacterial cell wall components influence the stability of Coxsackievirus B3

2021 ◽  
Author(s):  
Adeeba H. Dhalech ◽  
Tara D. Fuller ◽  
Christopher M. Robinson
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
Enteric Viruses ◽  
Enteric Virus ◽  
Coxsackievirus B3 ◽  
Bacterial Cell Wall ◽  
Cell Wall Components ◽  
E Coli ◽  
Wall Components

Enteric viruses infect the mammalian gastrointestinal tract and lead to significant morbidity and mortality worldwide. Data indicate that enteric viruses can utilize intestinal bacteria to promote viral replication and pathogenesis. However, the precise interactions between enteric viruses and bacteria are unknown. Here we examined the interaction between bacteria and Coxsackievirus B3, an enteric virus from the picornavirus family. We found that bacteria enhance the infectivity of Coxsackievirus B3 (CVB3) in vitro . Notably, specific bacteria are required as Gram-negative Salmonella enterica , but not Escherichia coli , enhanced CVB3 infectivity and stability. Investigating the cell wall components of both S. enterica and E. coli revealed that structures in the O-antigen or core of lipopolysaccharide, a major component of the Gram-negative bacterial cell wall, were required for S. enterica to enhance CVB3. To determine if these requirements were necessary for similar enteric viruses, we investigated if S. enterica and E. coli enhanced infectivity of poliovirus, another enteric virus in the picornavirus family. We found that while E. coli did not enhance the infectivity of CVB3, E. coli enhanced poliovirus infectivity. Overall, these data indicate that distinct bacteria enhance CVB3 infectivity and stability, and specific enteric viruses may have differing requirements for their interactions with specific bacterial species. Importance Previous data indicate that several enteric viruses utilize bacteria to promote intestinal infection and viral stability. Here we show that specific bacteria and bacterial cell wall components are required to enhance infectivity and stability of Coxsackievirus B3 in vitro . These requirements are likely enteric virus-specific as the bacteria for CVB3 differs from poliovirus, a closely related virus. Therefore, these data indicate that specific bacteria and their cell wall components dictate the interaction with various enteric viruses in distinct mechanisms.

The diagnosis of hepatitis C viral infection

2014 ◽  
Vol 155 (26) ◽  
pp. 1019-1023
Author(s):  
Judit Gervain
Keyword(s):  
Hepatitis C ◽  
Nucleic Acid ◽  
Viral Infection ◽  
Structural Changes ◽  
Viral Infections ◽  
Transient Elastography ◽  
Viral Nucleic Acid ◽  
Length Of Treatment ◽  
Subtype B

The successful therapy of hepatitis C viral infection requires that the illness is diagnosed before the development of structural changes of the liver. Testing is stepwise consisting of screening, diagnosis, and anti-viral therapy follow-up. For these steps there are different biochemical, serological, histological and molecular biological methods available. For screening, alanine aminotransferase and anti-HCV tests are used. The diagnosis of infection is confirmed using real-time polymerase chain reaction of the viral nucleic acid. Before initiation of the therapy liver biopsy is recommended to determine the level of structural changes in the liver. Alternatively, transient elastography or blood biomarkers may be also used for this purpose. Differential diagnosis should exclude the co-existence of other viral infections and chronic hepatitis due to other origin, with special attention to the presence of autoantibodies. The outcome of the antiviral therapy and the length of treatment are mainly determined by the viral genotype. In Hungary, most patients are infected with genotype 1, subtype b. The polymorphism type that occurs in the single nucleotide located next to the interleukin 28B region in chromosome 19 and the viral polymorphism type Q80K for infection with HCV 1a serve as predictive therapeutic markers. The follow-up of therapy is based on the quantitative determination of viral nucleic acid according to national and international protocols and should use the same method and laboratory throughout the treatment of an individual patient. Orv. Hetil., 2014, 155(26), 1019–1023.

Hygienic risk assessment by monitoring pathogens in municipal sewage

2002 ◽  
Vol 2 (3) ◽  
pp. 23-28 ◽  
Author(s):  
C.-H. von Bonsdorff ◽  
L. Maunula ◽  
R.M. Niemi ◽  
R. Rimhanen-Finne ◽  
M.-L. Hänninen ◽  
...  
Keyword(s):  
Enteric Viruses ◽  
Detection Methods ◽  
Municipal Sewage ◽  
Small Community ◽  
E Coli ◽  
Cryptosporidium Oocysts ◽  
High Concentrations ◽  
One Year ◽  
Enteric Protozoa ◽  
Day Care Centre

The purpose of this study was to monitor the levels of human enteric viruses and enteric protozoa and to relate their presence to the microbes used as hygienic quality indicators in domestic sewage from a small community in Finland during a period of one year. Genome-based sensitive detection methods for the pathogens selected (astro- and Norwalk-like viruses, Giardia and Cryptosporidium) have become available only recently and thus no earlier data was available. The effluent sewage is delivered into a river that serves as raw water for a larger town and the pathogens therefore constitute a health risk. The results showed that all the monitored pathogens could be detected, and that enteric viruses were present at considerable concentrations in sewage. High concentrations of astrovirus in raw sewage were observed during a diarrhea epidemic in the local day-care centre. The presence of viruses did not correlate with the monitored bacterial indicators of faecal contamination (coliforms, E. coli and enterococci) or with bacteriophages (somatic coliphages, F-specific RNA phages and B. fragilis phages). Giardia cysts and Cryptosporidium oocysts were detected from one sample (1/10) each.

Enteric viruses in drinking water supplies

2002 ◽  
Vol 2 (3) ◽  
pp. 17-22
Author(s):  
A.P. Wyn-Jones ◽  
J. Watkins ◽  
C. Francis ◽  
M. Laverick ◽  
J. Sellwood
Keyword(s):  
Drinking Water ◽  
Heavy Rainfall ◽  
Liquid Culture ◽  
Plaque Assay ◽  
Enteric Viruses ◽  
Enteric Virus ◽  
The Other ◽  
Raw Water ◽  
Rt Pcr ◽  
Water Supplies

Two rural spring drinking water supplies were studied for their enteric virus levels. In one, serving about 30 dwellings, the water was chlorinated before distribution; in the other, which served a dairy and six dwellings the water was not treated. Samples of treated (40 l) and untreated (20 l) water were taken under normal and heavy rainfall conditions over a six weeks period and concentrated by adsorption/elution and organic flocculation. Infectious enterovirus in concentrates was detected in liquid culture and enumerated by plaque assay, both in BGM cells, and concentrates were also analysed by RT-PCR. Viruses were found in both raw water supplies. Rural supplies need to be analysed for viruses as well as bacterial and protozoan pathogens if the full microbial hazard is to be determined.

Non-Viral Nucleic Acid Delivery: Key Challenges and Future Directions

2011 ◽  
Vol 8 (3) ◽  
pp. 235-244 ◽  
Author(s):  
Mahmoud Elsabahy ◽  
Adil Nazarali ◽  
Marianna Foldvari
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acid Delivery ◽  
Viral Nucleic Acid ◽  
Future Directions

Microbiological Examination of Vegetable Seed Sprouts in Korea

2009 ◽  
Vol 72 (4) ◽  
pp. 856-859 ◽  
Author(s):  
HOIKYUNG KIM ◽  
YOUNGJUN LEE ◽  
LARRY R. BEUCHAT ◽  
BONG-JUNE YOON ◽  
JEE-HOON RYU
Keyword(s):  
Microbiological Quality ◽  
Aerobic Bacteria ◽  
Escherichia Coli O157 ◽  
Enterobacter Sakazakii ◽  
Department Stores ◽  
E Coli ◽  
Traditional Markets ◽  
Radish Sprouts ◽  
Online Stores

Sprouted vegetable seeds used as food have been implicated as sources of outbreaks of Salmonella and Escherichia coli O157:H7 infections. We profiled the microbiological quality of sprouts and seeds sold at retail shops in Seoul, Korea. Ninety samples of radish sprouts and mixed sprouts purchased at department stores, supermarkets, and traditional markets and 96 samples of radish, alfalfa, and turnip seeds purchased from online stores were analyzed to determine the number of total aerobic bacteria (TAB) and molds or yeasts (MY) and the incidence of Salmonella, E. coli O157:H7, and Enterobacter sakazakii. Significantly higher numbers of TAB (7.52 log CFU/g) and MY (7.36 log CFU/g) were present on mixed sprouts than on radish sprouts (6.97 and 6.50 CFU/g, respectively). Populations of TAB and MY on the sprouts were not significantly affected by location of purchase. Radish seeds contained TAB and MY populations of 4.08 and 2.42 log CFU/g, respectively, whereas populations of TAB were only 2.54 to 2.84 log CFU/g and populations of MY were 0.82 to 1.69 log CFU/g on alfalfa and turnip seeds, respectively. Salmonella and E. coli O157:H7 were not detected on any of the sprout and seed samples tested. E. sakazakii was not found on seeds, but 13.3% of the mixed sprout samples contained this potentially pathogenic bacterium.

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