scholarly journals Bacterial and Viral Pathogens in Live Oysters: 2007 United States Market Survey

2010 ◽  
Vol 76 (9) ◽  
pp. 2754-2768 ◽  
Author(s):  
Angelo DePaola ◽  
Jessica L. Jones ◽  
Jacquelina Woods ◽  
William Burkhardt ◽  
Kevin R. Calci ◽  
...  

ABSTRACT Two samples of market oysters, primarily from retail establishments, were collected twice each month in each of nine states during 2007. Samples were shipped refrigerated overnight to five U.S. Food and Drug Administration laboratories on a rotating basis and analyzed by most probable number (MPN) for total and pathogenic Vibrio parahaemolyticus and V. vulnificus numbers and for the presence of toxigenic V. cholerae, Salmonella spp., norovirus (NoV), and hepatitis A virus (HAV). Levels of indicator organisms, including fecal coliforms (MPN), Escherichia coli (MPN), male-specific bacteriophage, and aerobic plate counts, were also determined. V. parahaemolyticus and V. vulnificus levels were distributed seasonally and geographically by harvest region and were similar to levels observed in a previous study conducted in 1998-1999. Levels of pathogenic V. parahaemolyticus were typically several logs lower than total V. parahaemolyticus levels regardless of season or region. Pathogenic V. parahaemolyticus levels in the Gulf and Mid-Atlantic regions were about two logs greater than the levels observed in the Pacific and North Atlantic regions. Pathogens generally associated with fecal pollution were detected sporadically or not at all (toxigenic V. cholerae, 0%; Salmonella, 1.5%; NoV, 3.9%; HAV, 4.4%). While seasonal prevalences of NoV and HAV were generally greater in oysters harvested from December to March, the low detection frequency obscured any apparent seasonal effects. Overall, there was no relationship between the levels of indicator microorganisms and the presence of enteric viruses. These data provide a baseline that can be used to further validate risk assessment predictions, determine the effectiveness of new control measures, and compare the level of protection provided by the U.S. shellfish sanitation system to those in other countries.

1983 ◽  
Vol 29 (10) ◽  
pp. 1261-1269 ◽  
Author(s):  
W. J. Robertson ◽  
R. S. Tobin

Fifteen stations, in two estuaries, along the Northumberland Strait of Nova Scotia were examined between June and September 1981 for a relationship between the concentrations of commonly monitored fecal indicator bacteria and the potential pathogens Candida albicans, Pseudomonas aeruginosa, and Vibrio parahaemolyticus. Increased densities of these three organisms were usually associated with high densities of indicator bacteria. Whereas C. albicans and P. aeruginosa occur in human fecal wastes, V. parahaemolyticus is indigenous to the marine environment and positively responds to elevated nutrient levels in sewage. There is also some evidence that these bacteria survive as long or longer in marine waters than the common indicator bacteria. While membrane-filtration techniques for the enumeration of C. albicans and P. aeruginosa proved satisfactory, a V. parahaemolyticus membrane-filtration method lacked specificity and was supplemented by a most-probable-number method. In marine recreational and shellfish waters, these three organisms could complement fecal coliforms and fecal streptococci as indicators of human fecal contamination.


2002 ◽  
Vol 68 (8) ◽  
pp. 3914-3918 ◽  
Author(s):  
David H. Kingsley ◽  
Gloria K. Meade ◽  
Gary P. Richards

ABSTRACT Hepatitis A virus (HAV) and Norwalk-like virus (NLV) were detected by reverse transcription-PCR in clams imported into the United States from China. An epidemiological investigation showed that these clams were associated with five cases of Norwalk-like gastroenteritis in New York State in August 2000 (Food and Drug Administration Import Alert 16-50). They were labeled “cooked” but appeared raw. Viral RNA extraction was performed by using dissected digestive tissues rather than whole shellfish meats; this was followed by glycine buffer elution, polyethylene glycol precipitation, Tri-Reagent treatment, and purification of poly(A) RNA with magnetic beads coupled to poly(dT) oligonucleotides. We identified HAV and NLV as genotype I and genogroup II strains, respectively. Both viruses have high levels of homology to Asian strains. An analysis of fecal coliforms revealed a most-probable number of 93,000/100 g of clam meat, which is approximately 300-fold higher than the hygienic standard for shellfish meats.


2021 ◽  
Vol 27 (2) ◽  
Author(s):  
Alok Kumar Singh ◽  
Anand Prakash Singh ◽  
Sanjay Srivastava

In India source of drinking water at Varanasi city for common people are tap water, well, hand pump, Ganga river and stored tank water collected from bore well. All water samples were studied to assess their bacteriological characteristics and suitability for potable purposes. A cross-sectional epidemiological method was adopted to investigate the drinking water of six different sites of Varanasi city. The bacteriological examination of water samples included the most probable number of presumptive coliforms, faecal coliforms, and total bacterial count. The results showed that the total coliform count was detected in all the site. In all the methods coliforms presence was indicated. Maximum number of coliform observed in all the seasons, were from river and well water followed by hand pump, tap water and stored tank. The most common group of indicator organisms used in water quality monitoring are coliforms. These organisms are representative of bacteria normally present in the intestinal tract of mammals including human. Contamination of water may occur through different way like sewage disposal in the river, seepage of bathing near sites, fecal excreta of human, bird and other animals. Improving and expanding the existing water treatment and sanitation systems are more likely to provide good, safe and sustainable sources of water in the long term.


2017 ◽  
Vol 11 (7) ◽  
pp. 74
Author(s):  
Adeeb Ahmed Ali AL Rahamneh

This study focuses on the amount of chemical properties and microbiology (T.D.S ,T.H,MPN) into the water provided by the environmental health from the private wells Al-Dlail laboratories in a Zarqa Governorate. The research problem focuses on the chemical properties and microbiology (T.D.S, T.H, MPN) of the amount of the water provided by the environmental health of the private wells of Al-Dlail laboratories in a Zarqa Governorate. The research object was to develop the necessary treatments for reducing the presence of unauthorized descent from T.D.S, T.H and MPN.The analytical research methodology was adopted for the case study analysis to achieve the purpose of this research which was to develop necessary treatments to reduce the presence of unauthorized descent from T.D.S, T.H and MPN. To achieve the study objectives, the study uses (Minitab). Based on the statistical analysis, the main results are:The Control Limits for the Total Dissolved Solid (T.D.S) and the Total Hardness (T.H) are within acceptable limits In the Control Limits for the Most Probable Number (MPN), some readings are beyond the extent of control. Also, there are two samples (15,16) that breach the specification and the bacterium Bacillus colon(MPN) limits, which means exceeding the allowed percentage of the limit.The researcher concluded that the Control Limits for the Total Dissolved Solid (T.D.S) are within acceptable limits and the Control Limits for the Total Hardness (T.H) are within acceptable limits. The researcher recommends that the international standard must be adopted in water treatment. 


2006 ◽  
Vol 69 (5) ◽  
pp. 1118-1125 ◽  
Author(s):  
R. DALLAIRE ◽  
D. I. LeBLANC ◽  
C. C. TRANCHANT ◽  
L. VASSEUR ◽  
P. DELAQUIS ◽  
...  

Microbial populations and the temperature of fresh broccoli were monitored at several steps of a supply chain by sampling 33 distinct lots of locally grown produce over two seasons during harvest, storage, wholesale handling, and retail display. Imported broccoli was also sampled, but only at retail display. Microbiological analyses were conducted on the florets of 201 local and 60 imported broccoli samples to determine populations of total aerobic bacteria (aerobic colony count), fecal coliforms, Escherichia coli, and Listeria monocytogenes. All the samples had mean aerobic colony counts ranging between 4 and 6 log CFU/g, but L. monocytogenes was not detected (limit of detection = 100 CFU/g). Fecal coliforms and E. coli (limit of detection = 20 most probable number per 100 g) were found in 22 of 126 samples of local broccoli collected at various steps of the production and distribution system during the first season. None was found in 75 samples collected in the second season. Fecal coliforms and E. coli were found in 2 of 60 imported broccoli samples. Broccoli temperatures were relatively well controlled throughout the production and distribution system. No clear change in produce microbial populations was evident between harvest and retail display, during both sampling seasons. However, a large experimental variability was found, possibly associated with the high variability of the initial levels of microbial populations on broccoli at harvest.


Author(s):  
Sidratun Nur Chowdhury ◽  
Nazifa Rafa ◽  
Sayed Mohammad Nazim Uddin ◽  
A. K. M. Moniruzzaman Mollah

Abstract Globally, unsafe water supplies due to contamination with fecal coliforms are major issues in urban slums. To determine the presence of microbial risk, water samples were collected from three slums in the port city Chattogram and the most probable number (MPN) method was used to test for the presence of fecal coliform. All of the samples tested positive by the MPN test. The highest count was 1,100 MPN/100 mL and the lowest count was 7.2 MPN/100 mL. Water stored in containers was prone to being more contaminated than water collected directly from the source. To understand the antibiotic resistivity of the coliform bacteria isolated from the water samples, antibiotic susceptibility was evaluated using the Kirby-Bauer disc method for six antibiotics. All the bacteria were 100% resistant to penicillin-G and ampicillin, and 91.7% showed resistance to amoxicillin and mecillinam. An integrated approach to water, sanitation, and hygiene education must be undertaken when providing sustainable interventions in slums.


1976 ◽  
Vol 39 (5) ◽  
pp. 322-324 ◽  
Author(s):  
W. H. ANDREWS ◽  
C. D. DIGGS ◽  
J. J. MIESCIER ◽  
C. R. WILSON ◽  
W. N. ADAMS ◽  
...  

To determine the relationship of most probable number (MPN) of the total and fecal coliform groups in shellfish and shellfish-growing waters to the presence of Salmonella in quahaugs (Mercenaria mercenaria), a microbiological survey of 214 samples of the quahaug, or hard-shell clam, was done over 24 months. For purposes of this study, waters were classified as safe for shellfish harvesting by one of two criteria: (a) a total coliform MPN of ≤ 70/100 ml of water or (b) a fecal coliform MPN value of ⩽ 14/100 ml of water. None of the quahaug samples harvested from waters meeting these standards contained Salmonella. Additionally, Salmonella was not detected in any of the quahaug samples meeting the wholesale market quality standard of 230 fecal coliforms per 100 g of shellfish as specified by the National Shellfish Sanitation Program. An increase in the total coliform and fecal coliform MPN of the waters more closely paralleled an increase in the fecal coliform MPN, as compared to the total coliform MPN of the quahaug meats. Five Salmonella serotypes, including Salmonella parathyphi B, were found singly and in combination in five (2.3%) of the quahaug samples in this survey.


Author(s):  
M.L. Baraquet ◽  
O.F. Camiletti ◽  
C.I. Moretti ◽  
L.E. Rodríguez ◽  
C. Vázquez

Background: The changes and the availability of processed foods have increased the demand for ready-to-eat foods, such as Minimally Processed Vegetables (MPVs). The purpose of this work was to evaluate the microbiological status and quality traits of the MPVs obtained from retail outlets of Córdoba, Argentina. Methods: Totally, 60 MPVs of 12 brands (30 single-ingredient salads and 30 mixed salad trays) were randomly sampled from different retail outlets of Córdoba, Argentina. The samples were analyzed according to international standards for Total Coliforms (TC), Fecal Coliforms (FC), Escherichia coli, Salmonella spp., Staphylococcus aureus, and Yeast and Molds (YM). The quality traits (respect to physical and sensory properties) of the MPVs were evaluated. Statistical analyses were performed with InfoStat. Results: All 60 MPV samples were positive for TC, ranging from 1.32 to 3.38 log Most Probable Number (MPN)/g. FC counts ranged from 0.30 to 1.95 log MPN/g. Out of 60 samples, 15 (25%) were positive for E. coli. Three brands of mixed trays were positive for S. aureus. Regarding sensory characteristics, the parameters such as freshness, turgid, normal color, decay, and dehydration were compliance in 42 out of 60 (70%) samples. Conclusion: Some MPVs sampled from Córdoba, Argentina showed low microbiological quality and imperfect quality traits.


2021 ◽  
Vol 23 (2) ◽  
pp. 146-152
Author(s):  
Bharati Shakya ◽  
Supri Raj Shrestha ◽  
Vinutha Silvanus

Water safety and quality are fundamental to human development and well-being. Yet, at least 2 billion people are using a drinking water source contaminated with feces worldwide. This study was conducted to assess the types of water supply, storage and methods of purification of drinking water and to examine the bacteriological quality of supplied and drinking water at household level by most probable number (MPN) test in Makalbari area in Gokarneshwor Municipality, Kathmandu. A total of 80 households were selected using simple random sampling technique and two samples (one from main water supply and another from drinking water, n=160 water samples) were collected from each household. Ethical clearance was taken from the Nepal Medical College Institutional Review Committee. SPSS version 16.0 was used for statistical analysis. Majority of water supply samples 65 (81.2%) were from tap, 11 (13.8%) were from well and 4 (5.0%) samples were from bore well. Bacteriologically, of the total water supply samples, 34 (42.5%) samples were excellent, 16 (20.0%) samples were suspicious and 30 (37.5%) samples were unsatisfactory by MPN index quality. Most of the households stored drinking water in the tanks 34 (42.5%). Most of the water samples 29 (36.3%) were directly consumed from the water supply without purification. Among the directly consumed drinking water samples, 13 (44.8%) samples showed unsatisfactory MPN index. Most commonly used methods of water purification was filtration 21 (26.2%). Of the total drinking water samples, 33 (41.25%) samples were positive for total coliform. Thirty-two (40.0%) of the households reported diarrhea in past one year. A highly significant association was found between MPN index of drinking water and occurrence of diarrhea in the households. The quality of the most of the water samples from water supply and drinking water were unsatisfactory. Inspite of this, drinking water was not purified in some of the households. Moreover, few of the drinking water samples were not potable even after purification. Therefore, community should be made aware to improve quality of drinking water in households.


2009 ◽  
Vol 92 (6) ◽  
pp. 1840-1845 ◽  
Author(s):  
Susan Alles ◽  
Mark Mozola ◽  
Thomas Hammack

Abstract A study was conducted to validate the GeneQuence Salmonella DNA hybridization assay, Performance Tested Method 030201, for detection of Salmonella spp. in peanut butter. The study was organized by the AOAC Research Institute under its Emergency Response Validation program. Peanut butter samples inoculated with S. Typhimurium were prepared by an independent laboratory and shipped to study participants for testing. The set of blind-coded test samples consisted of five uninoculated controls, 20 portions inoculated with S. Typhimurium at a low level [determined by most probable number (MPN) analysis to contain 1.1 CFU/25 g portion], and 20 portions inoculated with S. Typhimurium at a higher level (11 CFU/25 g portion by MPN analysis). Samples were tested in parallel by the GeneQuence method and by the U.S. Food and Drug Administration's Bacteriological Analytical Manual reference culture procedure. All five control samples were negative by both methods. For the low-level samples, the same two samples were positive by both the GeneQuence and reference methods. For the high-level samples, the same 19 samples were positive by both methods. All positive GeneQuence assays were confirmed by plating from associated broth cultures. Agreement between the GeneQuence and reference methods was 100. Sensitivity and specificity of the GeneQuence method were both 100. Because neither the low- nor the high-level samples yielded the desired fractional positive results (515 positives out of 20 samples), a second trial was conducted. Samples in the second trial contained 0.1 and 0.5 CFU/25 g portion for the low and high levels, respectively. All five control samples were negative by both methods. For the low-level samples, the same two samples were positive by both the GeneQuence and reference methods. For the high-level samples, the same three samples were positive by both methods. All positive GeneQuence assays were confirmed by plating from associated broth cultures. Sensitivity and specificity of the GeneQuence method were both 100. Although once again the desired level of fractional positive results was not obtained, there was 100 agreement between the GeneQuence and reference methods. Based on the results of both trials, it is recommended that the validated claims for Performance Tested Method 030201 be expanded to include peanut butter.


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