Multidrug Resistance in Large-Plasmid-Associated Presumptive Enterohaemorrhagic Escherichia coli Isolated from Contaminated Lake Water

Abstract

To determine the presence of enterohaemorrhagic Escherichia coli (EHEC), 50 water samples of three different lakes in Dhaka, Bangladesh were studied. A total of 90 strains were examined thoroughly to isolate sorbitol non-fermenting (NSF) E. coli. Twelve of 90 isolates (13.3%) from 5 samples were found to be sorbitol nonfermenter, which were further screened for rhamnose, cellobiose and sucrose fermentation. Eleven (12.2%) of 90 isolates also tested negative for cellobiose and sucrose fermentation, while only 3 (3.3%) of them were found to be rhamnose non-fermenting. Biochemical tests confirmed that 91.7% (11 of 12) of NSF strains were indole positive. Eleven NSF E. coli isolates survived at 45.5°C and mostly produced gas by fermentation within 24h. After antimicrobial susceptibility testing, 91.7% (n=11) of these isolates were found resistant to cephalexin, ampicillin and amoxicillin. Ceftazidime and nalidixic acid resistance was also observed in 75% (9 of 12) and 58.3% (7 of 12) isolates, respectively. Plasmid profile analysis revealed that nine (75%) strains harboured large plasmids of >35.8-140 megadaltons (MDa), four (33.3%) of which contained 60-MDa plasmid. Also, the large-plasmid-associated strains shared common behaviour in antimicrobial resistance and eight (88.9%) of these were resistant to four or more antibiotics. Our data suggest a possible association of source water contamination in Bangladesh with multidrug-resistant (MDR) EHEC, which is alarming to public health. DOI: http://dx.doi.org/10.3329/bjm.v28i1.11807 Bangladesh J Microbiol, Volume 28, Number 1, June 2011, pp 33-40

Prevalence and Characterization of Shigatoxigenic Escherichia Coli in Broiler Birds in Mymensingh

“…the environment by several researchers (Hossain et al, 2011;Islam et al, 2008;Alam et al, 2006). To the best of our knowledge, no work has yet conducted for the isolation and molecular characterization of STEC from cloacal swab sample of broiler birds in Bangladesh.…”

Prevalence and virulence determinants of Escherichia coli isolated from raw cows milk

“…In the present study, E.coli was recovered with 14.65% prevalence rate. Similarly, E. coli has been isolated by several researchers from raw milk of cattle and buffaloes (Caine et al, 2014;Islam et al, 2008;Hossain et al, 2011). Compering to present results, a higher percentage of E. coli in milk was reported by Bandyopadhyay et al (2012), Farzan et al (2012), Mohd et al (2013), Ali and Abdelgadir (2011) and Gwida and EL-Gohary (2013), who could isolate E. coli from raw milk in a percentage of 26.43,30.28, 33.96, 63 and 41.2% respectively.…”