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Enterococci are Gram-positive facultative anaerobic bacteria commonly found in the gastrointestinal tract of the mammals and birds. These cocci are isolated from urinary tract infections, bacteremia, endocarditis, and burn wounds in humans. The evolution of antibiotic-resistant enterococci raised a problem due to the possibility of the transmission of these organisms between poultry and human. Regarding this, the present study was conducted to evaluate the prevalence of Enterococcus species among companion birds and poultry in the Northeastern of Iran and determine the antibiotic susceptibility profile of enterococci. To this end, oral and cloacal swabs were collected from 150 caged birds. Antibiotic susceptibility profile was determined using the standard disk diffusion method. The results revealed that out of 150 samples, 56 (37.33%) cases contained enterococci. Most of the specimens (25.33%) were Enterococcus faecalis isolated from 6.66% of the samples. Additionally, 2.66% and 1.33% of the samples were contaminated with Enterococcus mundtii and Enterococcus gallinarum, respectively. Furthermore, Enterococcus malodoratus and Enterococcus raffinosus were isolated from 0.66% of the samples. The results revealed that all of the isolates of E. faecalis and E. faecium were resistant to more than five antimicrobial agents. Most of E. faecalis and E. faecium isolates showed resistance to Cefazolin, Tiamulin, Flumequine, and Cephalexin. Accordingly, the majority of the isolates had multidrug resistance to the tested antibiotics. In conclusion, the presence of multidrug-resistant enterococci in the birds living close to humans requires thorough observations due to the transmission of these organisms to humans.

Enterococci: advantages and drawbacks in biotechnology, a review. Enterococci are lactic acid bacteria that have been used for centuries in food processing. These microorganisms play a vital role in conservation (extension of shelf life) and in the bacteriological quality of food while keeping their nutritional and organoleptic properties. However, Enterococcus faecium and Enterococcus faecalis are indicators of faecal contamination and are also implicated in nosocomial diseases. The genetic plasticity (transfer of genetic elements) of these bacteria allows them not only to adapt to various ecosystems, but also to be vehicles of antibiotic resistances and bacterial virulence, which is of public health concern. Thus, the use of enterococci in the food industry is becoming controversial. However, enterococci are also involved in the fermentation of many foods (milk, vegetables, meats or fish) and are able to produce various antimicrobial molecules (e.g. lactic acid, bacteriocins or hydrogen peroxide) that make them indispensable in the food industry. Their use as probiotic must therefore be carefully characterized in order to prove their safety. The wide range of bacteriocins (enterocins) found in these bacteria could also be valorized by developing purification methods to replace the bacterial strains themselves by their enterocins in foodstuffs, therefore eliminating the risk of direct use of bacteria.

Wastewater treatment plants produce sludges which are likely to contain microbial pathogens, metallic trace elements and organic micropollutants. The aim of this study was to assess factors influencing the quality of raw sludge, i.e. freshly-produced and non-treated sludge. The survey of raw sludge quality was conducted each season over a year with controlled factors such as sludge type (primary or biological; rural or urban area origin) and seasonal evolution. Quality of raw sludge was characterized by the determination of microbiological (Salmonella spp., Escherichia coli, enterococci, spores of Clostridium perfringens) and chemical parameters (metallic trace elements, organic index). The organic index is a new parameter based on a gas chromatography method and developed in this study in order to estimate global organic semi-volatile load in sludge. Results showed significant differences in raw sludge quality depending on controlled factors. Thus, E. coli, and enterococci concentrations were higher in primary and biological urban raw sludge compared to biological rural sludge. Concentrations of Hg and organic semi-volatile compounds, estimated by organic index, were higher in primary urban raw sludge than biological sludges of rural or urban origin. As, Ni and Co loads were higher in biological rural raw sludge compared to primary and biological urban sludge. Spores of C. perfringens concentration in raw sludge was lower in autumn. Organic index in raw sludge was lower in spring and in summer. In conclusion, results showed that sludge quality varies significantly, depending of sludge type and seasonal evolution.

Abstract: The monitoring of infection by glycopeptide-resistant enterococci (GRE) is one of the main elements of hospital hygiene policy. It involves systematic rectal swabs in clinics at risk (asymptomatic carriage). Aim: We compare two GRE screening methods and evaluate a new kit associating multiplex PCR and hybridization (Génotype® Enterococcus, Hain Lifescience) on a panel of 448 samples collected over a 4-month period. Patients and methods: The first method is based on direct inoculation of the sample; the second one involves a preliminary enrichment phase followed by molecular diagnosis allowing the identification of species of enterococci as well as glycopeptide resistance genes. Results: All the resistant strains were isolated using the enrichment technique. The incidence of GRE (VanA) carriage was 0,55% (two out of 362 patients, two out of 448 isolates) with two Enterococcus faecium VanA. Six Enterococcus gallinarum VanC1 and two Enterococcus casseliflavus VanC2/C3 were also isolated and identified. The main clinics concerned are intensive care and hematology. The two patients with E. faecium VanA had been previously given glycopeptides for 10 days. For three strains, the molecular method allowed to correct prior erroneous results based on rapid identification (RapidID32Strep V2.0). Conclusion: The method using direct samples inoculation underestimates real incidence of GRE carriage. The performances of Génotype® Enterococcus molecular method, evaluated for other parameters using reference strains and DNA sequencing, offer new possibilities applicable to routine laboratory. [Copyright &y& Elsevier]

Abstract: This work was aimed to analyze trends in susceptibility to antibiotics among the main species of beta-hemolytic streptococci involved in community-acquired infections in human (Streptococcus pyogenes and Streptococcus agalactiae), or in animals (Streptococcus suis and Streptococcus uberis) and also among the main enterocci species, Enterococcus faecalis and Enterococcus faecium. Data were recorded since 1996 through the Onerba networks. S. pyogenes, as the other beta-hemolytic streptococci studied remained fully susceptible to beta-lactam antibiotics. However, susceptibility to macrolides is clearly decreasing in S. pyogenes. In 2002, only 62 to 65% of the strains according to the network considered, were susceptible to erythromycin. A similar trend was observed for S. agalactiae with only 75% of erythromycin susceptibility in 2002, and for both species isolated from animals S. suis and S. uberis, with respectively 35 and 76% of strains susceptible to erythromycin. In enterococci, susceptibility to beta-lactams remained stable between 2000 and 2004. Indeed, the susceptibility to aminopenicillins remained high in E. faecalis (about 98%), whereas the proportion of E. faecium isolates susceptible to these antibiotics were lower than 60%. From 1999 to 2004, various studies conducted in French hospitals showed that the vancomycin resistance among enterococci accounted for less than 2%. However, the recent emergence of glycopeptide resistant enterococci clusters in French hospitals is a matter of concern and emphasizes the need for an ongoing surveillance. Such trend in macrolide resistance among S. pyogenes or S. agalactiae should consequently lead to propose other alternatives in case of beta-lactam allergy, and for pharyngitis, to rethink the place of the culture for susceptibility testing. [Copyright &y& Elsevier]

Abstract: Screening for Vancomycin Resistant Enterococci (VRE) is recommended for preventing nosocomial infections with VRE. The aim of this study was to assess the performance of VCA3 agar (bioMérieux) in VRE isolation from fecal specimens. 220 specimens were cultured on VCA3 agar, which contains vancomycin and in parallel, on CAP agar (Oxoid), which is vancomycin-free. 36 vancomycin resistant enterococci were isolated: 24 isolates of Enterococcus faecium expressed a high-level resistance to vancomycin and 12 isolates of E. gallinarum/casseliflavus exhibited resistance at low-level. The sensitivity of VCA3 appeared greater than that of CAP for VRE isolation: 92% (22/24) vs 79% (19/24) for E. faecium (NS, P >0.05) ; 83% (10/12) vs 50% (6/12) for E. gallinarum/casselliflavus (NS, P >0.05). As expected, initial cultures of multiple gram positive organisms were far more frequent on CAP agar than on VCA3 agar. The isolation rate of vancomycin susceptible gram positive strains was impressively lower on VCA3 medium than on CAP medium. VCA3 agar avoided therefore additional subcultures, useless identification and susceptibility tests. In conclusion, VCA3 medium could be useful for the direct, rapid and selective isolation of VRE from fecal specimens. [Copyright &y& Elsevier]

Objectives – This 4 month study was made in six French pediatric centers, to assess the antimicrobial resistance of Gram-positive cocci. Methods – Staphylococcus aureus, enterococci, and coagulase negative staphylococci (CNS) were collected from June to October 1998. Only CNS isolated from blood samples were studied. Results – Methicillin resistance reached 7.8% for S. aureus isolates and 63% for CNS. About 41% of S. aureus strains were resistant to gentamicin, and all strains were susceptible to glycopeptides. CNS were more resistant to all antibiotics than S. aureus, except for pefloxacin. A decreased susceptibility to teicoplanin was observed in 3.3% of strains and only one strain was resistant. Among the 925 enterococci, seven strains (0.86%) had a VanA phenotype and only one had a VanB phenotype. Conclusions – These results prove the higher resistance of CNS. However, the resistance to glycopeptides of Gram positive cocci  remains low pediatrics in France. [Copyright &y& Elsevier]