Bacterial Indicators and Environmental Factors as Related to Contamination of Oysters by Enteroviruses

1980 ◽  
Vol 43 (2) ◽  
pp. 99-101 ◽  
Author(s):  
CHARLES P. GERBA ◽  
SAGAR M. GOYAL ◽  
IRINA CECH ◽  
GREGORY F. BOGDAN

Enteric viruses previously have been reported in marine waters and shellfish which met acceptable bacteriological standards for recreational use and shellfish harvesting. Unfortunately, previous data on occurrence of enteric viruses are limited and usually not quantitative. In this report, results of studies conducted along the upper Texas Gulf coast, where a substantial amount of quantitative virological data was collected, are compared to bacteriological indicators and other environmental factors on a statistical basis. A product-moment correlation matrix showed that there was a moderate correlation between viruses in water and total coliforms in water, total coliforms in oysters and fecal coliforms in oysters. However, presence of viruses in water was not found to be correlated with presence of viruses in oysters. The only significant regression coefficient found for the model relating the concentration of viruses in water to bacterial indicators and other environmental variables was concentration of coliforms in oysters. Multiple regression analysis showed that approximately 25% of the variance in the number of viruses detected in water was statistically accounted for by the linear correlation with the total coliforms in oysters. The amount of variation in the number of viruses explained by this indicator, however, was not large enough to make the concentration of coliforms in oysters a good predictor of the concentration of viruses in water. Furthermore, none of the bacterial or other environmental variables was found to be a good predictor of the concentration of viruses detected in oysters. Our failure to find a strong predictive relationship between viruses in marine water and in oysters, and the occurrence of viruses in high frequency in waters which met current bacteriological standards, indicate that these standards do not reflect the occurrence of enteroviruses in marine waters.

1986 ◽  
Vol 49 (8) ◽  
pp. 596-601 ◽  
Author(s):  
MARY TOWNSEND COLE ◽  
MARILYN B. KILGEN ◽  
LAWRENCE A. REILY ◽  
CAMERON R. HACKNEY

Field studies were conducted for 1 year to determine levels of enteroviruses in Louisiana Gulf Coast oysters and their overlying waters. Levels of human enteric viruses were compared with bacterial pathogens (Salmonella and Vibrio parahaemolyticus), fecal coliform levels, and physicochemical water parameters (pH, salinity, temperature, and conductivity). Samples of 20–30 oysters and 380 L of overlying water were collected monthly from both “open” and “closed” oyster growing areas. Enteric viruses were found predominantly in January and February. Viruses were isolated only from areas which exceeded the 14 fecal coliforms/100 ml standard for shellfish harvesting waters.


2007 ◽  
Vol 53 (6) ◽  
pp. 688-694 ◽  
Author(s):  
Annie Locas ◽  
Christine Barthe ◽  
Benoit Barbeau ◽  
Annie Carrière ◽  
Pierre Payment

A 1 year study was undertaken on groundwater that was a source of drinking water in the province of Quebec, Canada. Twelve municipal wells (raw water) were sampled monthly during a 1 year period, for a total of 160 samples. Using historic data, the 12 sites were categorized into 3 groups: group A (no known contamination), group B (sporadically contaminated by total coliforms), and group C (historic and continuous contamination by total coliforms and (or) fecal coliforms). Bacterial indicators (total coliform, Escherichia coli , enteroccoci), viral indicators (somatic and male-specific coliphages), total culturable human enteric viruses, and noroviruses were analyzed at every sampling site. Total coliforms were the best indicator of microbial degradation, and coliform bacteria were always present at the same time as human enteric viruses. Two samples contained human enteric viruses but no fecal pollution indicators (E. coli, enterococci, or coliphages), suggesting the limited value of these microorganisms in predicting the presence of human enteric viruses in groundwater. Our results underline the value of historic data in assessing the vulnerability of a well on the basis of raw water quality and in detecting degradation of the source. This project allowed us to characterize the microbiologic and virologic quality of groundwater used as municipal drinking water sources in Quebec.


2006 ◽  
Vol 66 (1a) ◽  
pp. 25-33 ◽  
Author(s):  
I. B. Cardone ◽  
S. E. Lima-Junior ◽  
R. Goitein

The purpose of this study is to ascertain whether variations in the limnological parameters of the Corumbataí river resulting from the discharge of a variety of wastes into its waters may be responsible for spatial shifts in the diet and capture of the armored catfish Hypostomus strigaticeps (Regan, 1907). Individuals were collected over a period of two years from two sites with similar physical, albeit distinct limnological characteristics. As a whole, the environmental variables (temperature, pH, dissolved oxygen, electrical conductivity, and total coliforms and fecal coliforms) of the two sites were found to vary significantly. The food items found in the guts of these armored catfish (sediments, diatoms, fungi hyphae, chlorophytes, cyanophytes and non-identified material) ranked differently in samples from the two sites. In the more polluted (site B), diatoms and chlorophytes ranked higher in the diet than in that of individuals caught in the more preserved location (site A). This fact may be related to the greater amount of organic material found at site B, which provides favorable environmental conditions for such algae and, consequently, for algivorous fishes. Even so, fewer fish were captured at site B than at site A, suggesting that although food is more abundant in the more polluted site, its limnological conditions appear, on the whole, to be less beneficial than the conditions at site A.


1980 ◽  
Vol 39 (3) ◽  
pp. 588-596 ◽  
Author(s):  
Raymond L. LaBelle ◽  
Charles P. Gerba ◽  
Sagar M. Goyal ◽  
Joseph L. Melnick ◽  
Irina Cech ◽  
...  

1993 ◽  
Vol 27 (3-4) ◽  
pp. 463-470 ◽  
Author(s):  
Robert Armon

2,187 drinking water samples from various locations in northern part of Israel were tested for bacteriophages presence/absence. Three major groups of bacteriophages were monitored (as related to bacterial host) : Somatic coliphages (host E.coli CN13), F-specific coliphages (host E.coli F+ amp), and Bacteroides fragilis phages (host B.fragilis HSP40). Simultaneously, monitoring of total coliforms and fecal coliforms has been performed. Correlation between bacteriophage group types and the standard water indicators such as coliforms and fecal coliforms was poor. The poor correlation may be attributed to dilution factor (large distance from the pollution source) and/or disinfection process. Presence frequency of the three bacteriophage groups was : 11.5 % somatic coliphages, 6.46 % F-specific coliphages and 5.48 % B.fragilis phages. Bacteriophages' presence plotted against presence of total coliforms, fecal coliforms, or both, revealed that F-specific coliphages and B.fragilis phages are closely related, whereas somatic coliphages group is different. Concentrates of several high volume water samples were tested for enteric viruses and B.fragilis phages presence correlation. All the samples were found negative for both parameters, however positive samples have not been detected. It is expected that continuous monitoring of drinking water for enteric viruses and concurrently for bacteriophages, will elucidate the index potential of bacteriophages. Bacteriophages presence in drinking water points to inadequate water treatment or contamination during the supply practice. Using human specific bacteriophages such as B.fragilis phages, will enable us to differentiate between pollution sources that contaminate drinking water. Future studies should be focused on phages presence as related to health risk assessment, similarly to human pathogens (bacteria, viruses and protozoa). Based on the collected data, F-specific and B.fragilis phages indicate towards reliable future index-organisms of drinking water pollution by sewage.


1983 ◽  
Vol 46 (6) ◽  
pp. 493-496 ◽  
Author(s):  
DOUGLAS A. WAIT ◽  
CAMERON RAY HACKNEY ◽  
ROBERT J. CARRICK ◽  
G. LOVELACE ◽  
MARK D. SOBSEY

Enteric bacteria and virus levels were determined in hard shell clams, Mercenaria mercenaria, harvested from areas open or closed for commercial shellfishing on the basis of total coliform levels in water. Four pairs of open and closed stations were sampled seasonally over a 1-year period. Enteric viruses were isolated from 3 of 13 100-g clam samples from open beds and 6 of 15 samples from closed beds. Salmonella was found in 1 of 15 samples from closed areas, but not in any samples from open areas. No Shigella or Yersinia were isolated from clams taken from either open or closed beds. Levels of Vibrio parahaemolyticus, an indigenous estuarine microorganism, were similar in clams from open and closed areas. No statistically significant difference was found in the occurrence of enteric viruses in clams from open and closed areas. Product-moment correlations between concentrations of enteric viruses and bacteria in clams or water demonstrated no statistically significant correlations between virus concentrations in clams and total coliforms or fecal coliforms in water or total coliforms, fecal coliforms, fecal streptococci or aerobic plate counts in clams.


2000 ◽  
Vol 46 (6) ◽  
pp. 565-576 ◽  
Author(s):  
Pierre Payment ◽  
Aminata Berte ◽  
Michèle Prévost ◽  
Bruno Ménard ◽  
Benoît Barbeau

A 300-km portion of the Saint Lawrence hydrological basin in the province of Québec (Canada) and 45 water treatment plants were studied. River water used by drinking water treatment plants was analyzed (6-L sample volumes) to determine the level of occurrence of bacterial indicators (total coliforms, fecal coliforms, and Clostridium perfringens) and pathogens (Giardia lamblia, Cryptosporidium, human enteric viruses). Pathogens and bacterial indicators were found at all sites at a wide range of values. Logistic regression analysis revealed significant correlations between the bacterial indicators and the pathogens. Physicochemical and treatment practices data were collected from most water treatment plants and used to estimate the level of removal of pathogens achieved under cold (0°C-4°C) and warm (20°C-25°C) water temperature conditions. The calculated removal values were then used to estimate the annual risk of Giardia infection using mathematical models and to compare the sites. The estimated range of probability of infection ranged from 0.75 to less than 0.0001 for the populations exposed. Given the numerous assumptions made, the model probably overestimated the annual risk, but it provided comparative data of the efficacy of the water treatment plants and thereby contributes to the protection of public health.Key words: public health, drinking water, health risk, pathogen occurrence.


Insects ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 152 ◽  
Author(s):  
Da-Yeong Lee ◽  
Dae-Seong Lee ◽  
Mi-Jung Bae ◽  
Soon-Jin Hwang ◽  
Seong-Yu Noh ◽  
...  

Odonata species are sensitive to environmental changes, particularly those caused by humans, and provide valuable ecosystem services as intermediate predators in food webs. We aimed: (i) to investigate the distribution patterns of Odonata in streams on a nationwide scale across South Korea; (ii) to evaluate the relationships between the distribution patterns of odonates and their environmental conditions; and (iii) to identify indicator species and the most significant environmental factors affecting their distributions. Samples were collected from 965 sampling sites in streams across South Korea. We also measured 34 environmental variables grouped into six categories: geography, meteorology, land use, substrate composition, hydrology, and physicochemistry. A total of 83 taxa belonging to 10 families of Odonata were recorded in the dataset. Among them, eight species displayed high abundances and incidences. Self-organizing map (SOM) classified sampling sites into seven clusters (A–G) which could be divided into two distinct groups (A–C and D–G) according to the similarities of their odonate assemblages. Clusters A–C were characterized by members of the suborder Anisoptera, whereas clusters D–G were characterized by the suborder Zygoptera. Non-metric multidimensional scaling (NMDS) identified forest (%), altitude, and cobble (%) in substrata as the most influential environmental factors determining odonate assemblage compositions. Our results emphasize the importance of habitat heterogeneity by demonstrating its effect on odonate assemblages.


2015 ◽  
Vol 75 (2 suppl) ◽  
pp. 81-84 ◽  
Author(s):  
R Linden ◽  
MV Antunes ◽  
LS Heinzelmann ◽  
JD Fleck ◽  
R Staggemeier ◽  
...  

<p>The preservation of hydric resources is directly related to fecal contamination monitoring, in order to allow the development of strategies for the management of polluting sources. In the present study, twenty-five water samples from six water public supply collection sites were used for the evaluation of the presence of caffeine, total and fecal coliforms. Caffeine was detected in all samples, with concentrations ranging from 0.15 ng mL<sup>–1</sup> to 16.72 ng mL<sup>–1</sup>. Total coliforms were detected in all samples, with concentrations in the range of 52 NMP/100 mL to higher than 24196 NMP/100 mL, whether the concentration range for fecal coliforms was in the range of below 1 NMP/100 mL to 7800 NMP/100 mL. No significant correlation was found between total coliforms and caffeine concentrations (rs = 0.35, p = 0.09). However, a moderate correlation between fecal coliforms and caffeine concentrations was found (rs = 0.412, p <0.05), probably indicating a human source for these bacteria. Caffeine determination in water may be a useful strategy to evaluate water contamination by human fecal waste.</p>


2012 ◽  
Vol 72 (3) ◽  
pp. 545-552 ◽  
Author(s):  
CT. Callil ◽  
D. Krinski ◽  
FA. Silva

The unionid Anodontites trapesilais (Lamarck, 1819) like most freshwater mussels is a parasite of fish. So it is trivial to assume that the availability of hosts is an important factor for the maintenance of unionoid populations. What seems obvious is not always so easy to demonstrate. This study proposes to investigate the effects of abiotic and biotic variables related to the incubation of larvae in A. trapesialis. For this, we estimate different biological indexes and try to capture the dimensionality of the fish, along with the temporal variation of environmental variables. From the application of a CCA, it was demonstrated that there was a synchronicity among the factors and variables proposed here, and we infer that the flood pulse acts as a synergistic factor in this process.


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