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Monitoring bacterial faecal contamination in waters using multiplex real-time PCR assay for Bacteroides spp. and faecal enterococci
R.M Agudel, F Codony, B Adrado, M Fittipaldi, G Pe uela, J Morató
Water SA , 2010,
Abstract: Monitoring of sanitary quality or faecal pollution in water is currently based on quantifying some bacterial indicators such as Escherichia coli and faecal enterococci. Using a multiplex real-time PCR assay for faecal enterococci and Bacteroides spp., the detection of faecal contamination in non-treated water can be done in a few hours, reducing the analysis time to 2 h. The conventional method based on cultures was compared with a multiplex assay procedure for Bacteroides spp. and faecal enterococci with an internal inhibition control. Out of 74 water samples from different sources analyzed, using both procedures, 54 were true positives and 6 true negatives, 12 samples were real-time PCR positive and culture-negative whereas 2 were real-time PCR negative and culture-positive. In conclusion, 89.2% of the samples were found to be positive with real-time PCR and 75.7% with plate cultures. Detection levels were much higher when using the multiplex real-time PCR assay, based on the higher number of positive samples in comparison with conventional microbiology. The feasibility of multiple reactions in the monitoring of faecal contamination has been demonstrated along with fast quantification of the faecal load. Such procedure can be performed in less than 3 h. This work extends the use of multiplex real-time PCR for environmental analysis, demonstrating the feasibility of these procedures in monitoring faecal pollution of water samples.
Enterococci in river Ganga surface waters: Propensity of species distribution, dissemination of antimicrobial-resistance and virulence-markers among species along landscape
Pushpa Lata, Siya Ram, Madhoolika Agrawal, Rishi Shanker
BMC Microbiology , 2009, DOI: 10.1186/1471-2180-9-140
Abstract: Enterococci density (χ2: 1900, df: 1; p < 0.0001) increased from up-to-down gradient sites in the landscape. Species diversity exhibit significant (χ2: 100.4, df: 20; p < 0.0001) and progressive distribution of E. faecalis, E. faecium, E. durans and E. hirae down the gradient. Statistically discernible (p: 0.0156 – < 0.0001) background pool of resistance and virulence was observed among different Enterococcus spp. recovered from five sites in the up-to-down gradient landscape. A significant correlation was observed in the distribution of multiple-antimicrobial-resistance (viz., erythromycin-rifampicin-gentamicin-methicillin and vancomycin-gentamicin-streptomycin; rs: 0.9747; p: 0.0083) and multiple-virulence-markers (viz., gelE+esp+; rs: 0.9747; p: 0.0083; gelE+efaA+; rs: 0.8944; p: 0.0417) among different Enterococcus spp.Our observations show prevalence of multiple-antimicrobial-resistance as well as multiple-virulence traits among different Enterococcus spp. The observed high background pool of resistance and virulence in enterococci in river waters of populous countries has the potential to disseminate more alarming antimicrobial-resistant pathogenic bacteria of same or other lineage in the environment. Therefore, the presence of elevated levels of virulent enterococci with emerging vancomycin resistance in surface waters poses serious health risk in developing countries like India.Enterococci, commensal organisms in gastrointestinal tract of human and animals have emerged as a leading cause of nosocomial infections [1]. Enterococcus faecalis (E. faecalis) and E. faecium are the two major pathogenic species in human, with sporadic infections caused by E. durans, E. hirae and other enterococci [2]. The presence of enterococci as an indicator of fecal contamination has been used in management of recreational water quality standards as it correlates best with the incidence of swimming-related illnesses [3,4]. Various virulence traits such as gelatinase (gelE), ente
Enterococci: yin - yang microbes  [cached]
Andreja ？an？ek Majheni？
Mljekarstvo , 2006,
Abstract: This review deals with the duality of enterococci, which can be illustrated by their yin - yang behaviour. The rough nature of this specific group of lactic acid bacteria promotes their dissemination in various environments where they significantly influence the outcome of a certain process. In the technological meaning, enterococci are leading microbes in fermentation processes of traditional foods, where their detrimental spoilage activities are equally significant. As therapeutics, enterococci manifest the probiotic properties through their positive effects on maintaining of the normal intestinal microflora, on stimulation of the immune system, on improved nutritional value of food and with the production of antimicrobial compounds (bacteriocins). At the same time, enterococci present an emerging pool of opportunistic pathogens for humans as they cause disease, possess agents for antibiotic resistance and their transfer mechanisms, and are frequently armed with potential virulence factors. Despite the yin - yang characteristics of enterococci, the long history of safe use of certain strains of enterococci in food/feed, and reliable identification and classification of enterococci with phenotypic methods supported with modern genetic tools, enables selection of promising enterococci, which could be safely used as starter cultures or food/feed additives.
Assessing the East Bay of Galveston Bay, Texas for Coliform Bacteria in Recreational Water  [PDF]
Tommy Quach, Luis Colon, Akintayo Akinrinlola, Jesse Bell, Sonya Good
Open Journal of Marine Science (OJMS) , 2016, DOI: 10.4236/ojms.2016.64039
Abstract: The Galveston Bay beach is a widely used recreational area that remains a concern in terms of water quality. There are many factors that contribute to its pollution such as fecal matter entering the bay due to overflow of the sewage system and run offs.？ Thus, evaluating the water quality for fecal matter and other pollutants is continuously monitored by citizen scientists and research groups throughout the Galveston Bay. The investigation utilizes the colorimetric response of coliform at three test sites along the East Bay of Galveston. Each response is positive for coliform that may indicate the presence of fecal matter. Other scientists have denoted the presence of fecal matter in the Galveston Bay at two sites using enterococci indicator which may be more associated with human fecal matter. The analyses show that the recreational water is likely not a threat since its levels were low. However, the need for analyses based on EPA protocols and standards is necessary to better access water pollution due to fecal matter in the Galveston Bay area.
A pesca amadora recreativa de cani o na praia do Cassino, RS: necessidade de informa es ecológicas aliada à espécie alvo Recreational Fishing at Cassino Beach, Southern Brazil: The need of ecological information associated to target species
T. P. Basaglia,J. P. Vieira
Brazilian Journal of Aquatic Science and Technology , 2005,
Abstract: Cassino’s Beach is one of the most popular surf casting recreational fishing ground of southern Brazil and king-fish (Menticirrhus spp) is the preferential target. This paper describes the profile of the fishermen that use Cassino’s Beach. The dada analyzed came form 446 survey questionnaires collected monthly from 1999 to 2001 along of 22 km (from the Jetties of Rio Grande to the Altair ship). The king-fish were the target fish, representing 89.9% of the intention of casting and they were the most abundantly caught species (79.9%). It is estimated that during summer catches range from 1 to 2.5 ton of king-fish, and more than 50% of them are not fully grown and developed sexually. Our results suggest the need of more studies in order to improve ecological information about this special fishery and to preserve the environment. Cassino’s Beach is one of the most popular surf casting recreational fishing ground of southern Brazil and king-fish (Menticirrhus spp) is the preferential target. This paper describes the profile of the fishermen that use Cassino’s Beach. The dada analyzed came form 446 survey questionnaires collected monthly from 1999 to 2001 along of 22 km (from the Jetties of Rio Grande to the Altair ship). The king-fish were the target fish, representing 89.9% of the intention of casting and they were the most abundantly caught species (79.9%). It is estimated that during summer catches range from 1 to 2.5 ton of king-fish, and more than 50% of them are not fully grown and developed sexually. Our results suggest the need of more studies in order to improve ecological information about this special fishery and to preserve the environment.
Vancomycin resistant enterococci (VRE) in Swedish sewage sludge
Leena Sahlstr？m, Verena Rehbinder, Ann Albihn, Anna Aspan, Bj？rn Bengtsson
Acta Veterinaria Scandinavica , 2009, DOI: 10.1186/1751-0147-51-24
Abstract: During a four month long study, sewage sludge was collected weekly and cultured for VRE. The VRE isolates from sewage sludge were analysed and compared to each other and to human and chicken VRE isolates by biochemical typing (PhenePlate), PFGE and antibiograms.Biochemical typing (PhenePlate-FS) and pulsed field gel electrophoresis (PFGE) revealed prevalence of specific VRE strains in sewage sludge for up to 16 weeks. No connection was found between the VRE strains isolated from sludge, chickens and humans, indicating that human VRE did not originate from Swedish chicken.This study demonstrated widespread occurrence of VRE in sewage sludge in the studied WWTP. This implies a risk of antimicrobial resistance being spread to new farms and to the society via the environment if the sewage sludge is used on arable land.Enterococci are naturally occurring bacteria in the intestinal tract of humans and animals, and are often used as indicators of faecal contamination in water [1]. Enterococci are resistant to environmental stress and may persist for a long time outside their hosts. They are not considered severe pathogenic organisms, but some species, e.g. Enterococcus (E.) faecalis and E. faecium, are important causes of nosocomial infections [2,3]. Antimicrobial resistance in strains causing nosocomial infections is a growing problem and vancomycin resistant enterococci (VRE) in particular are considered a serious threat in hospitals around the world [4]. Vancomycin is often used as a last resort in treatment of antibiotic resistant gram-positive bacterial infections caused by organisms such as multi-resistant enterococci and methicillin resistant staphylococci. In the USA, the prevalence of VRE is mainly documented as nosocomial infection in humans [5,6]. In Europe, nosocomial infections with VRE are less common, but such bacteria are widespread among healthy livestock [5] as a consequence of previous use of avoparcin (an analogue to vancomycin) as a feed additive in an
Immunochemical characterization of polysaccharide antigens from six clinical strains of Enterococci
Carolyn T Hsu, Amanda L Ganong, Barbara Reinap, Zafiria Mourelatos, Johannes Huebner, Julia Y Wang
BMC Microbiology , 2006, DOI: 10.1186/1471-2180-6-62
Abstract: We cultured large batches of each strain, isolated sufficient quantities of polysaccharides, analyzed their chemical structures, and compared their antigenic specificity. Three classes of polysaccharides were isolated from each strain, including a polyglucan, a teichoic acid, and a heteroglycan composed of rhamnose, glucose, galactose, mannosamine, and glucosamine. The polyglucans from all six strains are identical and appear to be dextran. Yields of the teichoic acids were generally low. The most abundant polysaccharides are the heteroglycans. The six heteroglycans are structurally different as evidenced by NMR spectroscopy. They also differ in their antigenic specificities as revealed by competitive ELISA. The heteroglycans are not immunogenic by themselves but conjugation to protein carriers significantly enhanced their ability to induce antibodies.The six clinical strains of enterococci express abundant, strain-specific cell-surface heteroglycans. These polysaccharides may provide a molecular basis for serological typing of enterococcal strains and antigens for the development of vaccines against multi-drug resistant enterococci.Enterococci are part of the normal flora of the gastrointestinal and genitourinary tracts and colonize the bowels of more than 90% of healthy humans [1]. Enterococci are opportunistic pathogens with generally low virulence, but their intrinsic and increasing acquired resistance to multiple drugs have made them a major cause of nosocomial infections [2,3]. Enterococci are intrinsically resistant to a number of antimicrobial drugs, including cell wall-active agents, many commercially available aminoglycosides, and vancomycin – the antibiotic of last resort against multidrug-resistant bacteria [4-7]. Enterococci can cause severe invasive infections such as peritonitis, endocarditis, meningitis, and abscesses in the urinary tract, along surgical sites, the lung and pleural spaces, facial sinuses, and peritoneal cavities [8,9]. Because entero
Absence of intestinal colonization by vancomycin-resistant enterococci in nonhuman primates
Xavier, Diego Batista;Rosa, Adriana Helena;Sena, Hilana dos Santos;Teixeira, Danillo Simonini;Tomaz, Carlos;Titze-de-Almeida, Ricardo;
Pesquisa Veterinária Brasileira , 2010, DOI: 10.1590/S0100-736X2010000600004
Abstract: the animal reservoirs of vancomycin-resistant enterococci (vre) have important role in the epidemiology of the bacteria and resistant genes. the present work searched fecal samples taken off nonhuman primates for the presence of vre. resistance profiles, virulence traits, and genetic variability among enterococci isolates were also analyzed. the samples included capuchin monkeys (cebus apella, n=28) and common marmoset (callithrix penicillata, n=37) housed in the primate center of the university of brasília, brazil. most individuals were captive monkeys from the central-west and south-east regions of brazil (n=48). we collected rectal swabs and carried out selective isolation followed by multiplex polymerase chain reaction (pcr) to identify species and resistance genes. no vana or vanb-containing enterococci were found. the carriage rates ranged from 1.5% for the vanc-type e. casseliflavus and e. gallinarum until 12.3% (n=8) for enterococcus faecalis. all e. faecalis isolates showed susceptibility to vancomycin, teicoplanin, ampicillin, gentamicin, and streptomycin. the virulence genes ace and esp were prevalent (100.0%, 87.5%). multilocus variable number of tandem repeats (mlva) revealed diversity in the number of repeats among e. faecalis isolates and targets, which was higher for espc, efa5, and efa6. we identified six different mlva genotypes that were divergent from those described in human beings. also, they were clustered into two genogroups that showed host-specificity for the species cebus apella or callithrix penicillata. in conclusion, no vana- or vanb-containing enterococci were found colonizing those primate individuals. this finding suggested that the primate individuals investigated in our study are not directly involved in the epidemiological chain of high-level vancomycin-resistant genes vana or vanb in brazil. our study also showed that e. faecalis isolated from nonhuman primates carry virulence traits and have ability to spread their lineages amon
Generic Modelling of Faecal Indicator Organism Concentrations in the UK  [PDF]
John Crowther,Danyel I. Hampson,Ian J. Bateman,David Kay,Paulette E. Posen,Carl M. Stapleton,Mark D. Wyer
Water , 2011, DOI: 10.3390/w3020682
Abstract: To meet European Water Framework Directive requirements, data are needed on faecal indicator organism (FIO) concentrations in rivers to enable the more heavily polluted to be targeted for remedial action. Due to the paucity of FIO data for the UK, especially under high-flow hydrograph event conditions, there is an urgent need by the policy community for generic models that can accurately predict FIO concentrations, thus informing integrated catchment management programmes. This paper reports the development of regression models to predict base- and high-flow faecal coliform (FC) and enterococci (EN) concentrations for 153 monitoring points across 14 UK catchments, using land cover, population (human and livestock density) and other variables that may affect FIO source strength, transport and die-off. Statistically significant models were developed for both FC and EN, with greater explained variance achieved in the high-flow models. Both land cover and, in particular, population variables are significant predictors of FIO concentrations, with r2 maxima for EN of 0.571 and 0.624, respectively. It is argued that the resulting models can be applied, with confidence, to other UK catchments, both to predict FIO concentrations in unmonitored watercourses and evaluate the likely impact of different land use/stocking level and human population change scenarios.
Bacteriological Monitoring and Sustainable Management of Beach Water Quality in Malaysia: Problems and Prospects  [cached]
Ayokunle Christopher Dada,Ahmad Asmat,Usup Gires,Lee Yook Heng
Global Journal of Health Science , 2012, DOI: 10.5539/gjhs.v4n3p126
Abstract: Despite the growing demand of tourism in Malaysia, there are no resolute efforts to develop beaches as tourist destinations. With no incentives to monitor public beaches or to use them in a sustainable manner, they might eventually degenerate in quality as a result of influx of pollutants. This calls for concerted action plans with a view to promoting their sustainable use. The success of such plans is inevitably anchored on the availability of robust quality monitoring schemes. Although significant efforts have been channelled to collation and public disclosure of bacteriological quality data of rivers, beach water monitoring appears left out. This partly explains the dearth of published information related to beach water quality data. As part of an on-going nation-wide surveillance study on the bacteriological quality of recreational beaches, this paper draws on a situation analysis with a view to proffering recommendations that could be adapted for ensuring better beach water quality in Malaysia.
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