Pseudomonas aeruginosa has emerged as a major healthcare associated pathogen that creates a serious public health disaster in both developing and developed countries. In this work we aimed at studying the occurrence of metallo-beta-lactamase (MBL) producing P. aeruginosa in a healthcare setting in Alexandria, Egypt. This cross sectional study included 1583 clinical samples that were collected from patients admitted to Alexandria University Students' Hospital. P. aeruginosa isolates were identified using standard microbiological methods and were tested for their antimicrobial susceptibility patterns using single disc diffusion method according to the Clinical and Laboratory Standards Institute recommendations. Thirty P. aeruginosa isolates were randomly selected and tested for their MBL production by both phenotypic and genotypic methods. Diagnostic Epsilometer test was done to detect metallo-beta-lactamase enzyme producers and polymerase chain reaction test was done to detect imipenemase (IMP), Verona integron-encoded (VIM) and Sao Paulo metallo-beta-lactamase (IMP) encoding genes. Of the 1583 clinical samples, 175 (11.3%) P. aeruginosa isolates were identified. All the 30 (100%) selected P. aeruginosa isolates that were tested for MBL production by Epsilometer test were found to be positive; where 19 (63.3%) revealed blaSPM gene and 11 (36.7%) had blaIMP gene. blaVIM gene was not detected in any of the tested isolates. Isolates of MBL producing P. aeruginosa were highly susceptible to polymyxin B 26 (86.7%) and highly resistant to amikacin 26 (86.7%). MBL producers were detected phenotypically by Epsilometer test in both carbapenem susceptible and resistant P. aeruginosa isolates. blaSPM was the most commonly detected MBL gene in P. aeruginosa isolates.

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Swimming pools have been identified as posing some public health risks to users due to either bacterial or chemical contamination. As a result, maintaining good swimming pool water quality is an important issue in preventing health risks for bathers. This study aimed to evaluate the bacteriological quality of some swimming pools in Alexandria and to investigate the prevalence of Staphylococcus aureus (S. aureus) in water samples. A total of 120 water samples from 10 swimming pools were collected. Bacteriological analysis included heterotrophic plate count (HPC) using pour plate method; enumeration of total coliforms (TC), Escherichia coli (E. coli) and S. aureus by membrane filtration technique. Antimicrobial susceptibility testing was performed on isolated S. aureus. Residual chlorine and pH were measured at swimming pools side. HPC was the least complying microbial parameter, followed by TC. S. aureus was recovered from 18 samples; 9 isolates were methicillin resistant S.aureus (MRSA), compared to E. coli that was detected in 7 samples. HPC and TC showed statistically significant correlations with all investigated parameters. In conclusion, the examined pools showed poor quality regarding all examined parameters collectively according to the Egyptian guidelines, which necessitates implementation of proper measures to ensure safer environment in swimming pools.

Introduction Dental unit waterlines (DUWLs) are notorious for being contaminated with different bacterial species including the opportunistic pathogen Pseudomonas aeruginosa which poses a risk to patients and professionals. This work aimed at studying the occurrence and biofilm-forming ability (BFA) of P. aeruginosa in the output of DUWLs in a dental center in Egypt. Methods Water samples were collected from the outlets of the high-speed hand piece, the air/water syringe and the cup filler waterlines. Bacteriological analysis included heterotrophic plate count (HPC), isolation and identification of P. aeruginosa and determination of the antimicrobial susceptibility and the BFA of the isolates by tissue culture plate (TCP) method and tube method (TM).Results The average concentration of HPC bacteria in the output of the 3 DUWLs was 2.9×10 4 CFU/mL where 88.3% of the samples exceeded the Egyptian standards for drinking water (˂50 CFU/mL). P. aeruginosa was isolated from nine cup filler samples (which had a water source different from the other waterlines). The isolates were sensitive to all tested antimicrobials. Of these nine isolates, 6, 5 and 4 were positive for BFA by TCP, modified TCP and TM, respectively.Conclusions More stringent measures are required to ensure safer dental water; as the majority of studied samples exceeded the required HPC bacterial limit and P. aeruginosa isolates were detected. P. aeruginosa isolates from DUWLs may not be as resistant to antibiotics as what is reported in the literature about clinical isolates. Some P. aeruginosa isolates can colonize DUWLs despite their inability to form biofilms in experimental testing.

Background: Fresh vegetables and ready-to-eat salads (RTES) are essential components of human diet. Despite their benefits, they remain a major public health concern, because they have been implicated in foodborne illness outbreaks in numerous countries. Aim: The present study aimed to assess the bacteriological quality of some fresh vegetables and RTES in Alexandria, Egypt. Materials and Methods: This cross-sectional study included 121 samples of vegetables and RTES that were randomly purchased from different markets, restaurants, and street vendors in three districts in Alexandria. All samples were subjected to heterotrophic plate count using pour plate method; detection and enumeration of total coliforms, fecal coliforms and Escherichia coli by multiple tube dilution method; and isolation and detection of Salmonella spp. using standard microbiological methods. Results: The aerobic colony count (ACC) for the 71 tested fresh vegetable samples ranged from 2.0 to 10.4 log CFU/g. Green pepper had the highest ACC mean value (8.4 log CFU/g), whereas lettuce showed the lowest ACC mean (5.1 log CFU/g). Fecal coliforms were detected in 90.1% of tested vegetable samples and 66% of the examined RTES samples. Of the 22 street-vended RTES samples, 18.2% were significantly unsatisfactory regarding E. coli. Salmonella spp. was not detected in any of the examined samples. Conclusion: All examined samples were contaminated and yielded growth of aerobic mesophilic bacteria with varying densities. According to the Public Health Laboratories guidelines, only street-vended RTES samples yielded unsatisfactory levels of E. coli, which indicates the need for close supervision and regular inspection of hygienic practices and preparation methods of street-vended salads.