Occurrence of Vibrio cholerae non-O1 in three wastewater treatment plants in Agadir (Morocco)

Abstract

A total of 21 isolates of Vibrio cholerae non-O1 strains were isolated from three wastewater treatment plants in Agadir, Morocco. The isolates were analyzed by biochemical analysis, antibiogram, pulsed-field gel electrophoresis and the MALDI-TOF patterns of their protein masses were compared. Over 67% of isolates were susceptible to antimicrobial agents tested and 14% proved resistant to both trimethoprim-sulfamethoxazole and nalidixic acid. Typing by pulsed-field gel electrophoresis with NotI digestion revealed that the V. cholerae non-O1 strains from Agadir (Morocco) have a lower level of genetic homogeneity, the restriction patterns of whole-chromosomal DNA grouped the V. cholerae O1 and V. alginolyticus strains into a separate cluster from V. metschnikovii and V. cholerae non-O1 isolates. Furthermore, to gain additional analytical accuracy and reliability in the analysis we used dendrogram based on MALDI-TOF spectral patterns generated by the BioTyper 1.1 TM software. All m/z signatures of all strains tested indicate that the mass spectral data contained sufficient information to distinguish between strains of V. cholerae.

Rapid identification ofVibrio parahaemolyticusisolated from shellfish, sea water and sediments of the Khnifiss lagoon, Morocco, by MALDI-TOF mass spectrometry

“…; Eddabra et al . ). Another disadvantage of molecular methods is a weaker reproducibility because of variations in band intensity and the presence of some minor bands, requiring the use of other PCR methods for typing V. parahaemolyticus (Wong and Chih‐Hsueh ).…”

“…An increase in the frequency of V. parahaemolyticus associated-infections has heightened the need for a rapid and reliable method for the identification of V. parahaemolyticus strains (Daniels et al 2000;Nair et al 2007). The major advantages of using MALDI-TOF/ MS-based protein mass spectral fingerprinting for the identification of micro-organisms as well as for their differentiation at the subspecies level are the ease to treat large series, the analytic speed, with relatively simple sample preparation techniques, the potential for the identification of mixed cultures and a rapid identification of candidate biomarkers, even when minimal genetic data are available (Eddabra et al 2011). The accuracy and speed of data acquisition make MALDI-TOF MS a powerful tool especially suited for environmental monitoring and detection of biological hazards in food processing plants and in the hospital.…”

“…Furthermore, Marshall et al (1999), indicated that DNA of isolates subjected to PFGE following ApaI macro-restriction was often degraded and the choice of the restriction enzyme during PFGE analysis of V. parahaemolyticus isolates may affect the typing results. However, it was recently reported that MALDI-TOF MS more efficiently discriminates isolates of other Vibrio species (Dieckmann et al 2010;Eddabra et al 2011). Another disadvantage of molecular methods is a weaker reproducibility because of variations in band intensity and the presence of some minor bands, requiring the use of other PCR methods for typing V. parahaemolyticus (Wong and Chih-Hsueh 2001).…”

Isolation and antibiotic profile ofVibriospp. in final effluents of two wastewater treatment plants in the Eastern Cape of South Africa

“…The target genes (Table 1) specific for the identification of these pathotypes were not detected in the tested isolates. With the exception of V. cholera which could not be tested the tested strains are not ubiquitous to the natural fresh or salt aquatic environment as are the V. cholera [11]. V. fluvialis, V. parahaemolyticus and V. vulnificus are reported as the most frequently encountered pathogenic Vibrios in marine environments, coastal, estuaries and brackish waters as well as seafood, which is considered a natural habitat for this strains of Vibrio spp.…”

“…The aquatic environment have been identified to be a medium of transmission of this organism through which the isolation of the organism has been found in seafood [7,9,10]. The isolation of the microorganism from raw sewerage as well as the final treated effluent showed that wastewater treatment plants do not remove or inactivate all pathogenic microorganisms [11,12] and hence Wastewater has been implicated in the distribution of Vibrio in the environment and surface water [13,14]. Study have shown the presence of high level antibiotic resistance Vibrio cholera e in the final effluent of stabilization pond revealing the imminent danger of poorly treated effluent [15].…”