Food of non-animal origin is a major component of the human diet and has been considered to pose a low risk from the point of view of bacteriological safety. However, an increase in the number of outbreaks of illness caused by such pathogens and linked to the consumption of fresh fruit and vegetables have been reported from around the world recently. Salmonella spp., STEC (Shiga toxin producing Escherichia coli) and Listeria monocytogenes are among the most frequently identified agents. Additionally, the transmission of antibiotic resistant strains including also the methicillin resistant S. aureus (MRSA) to humans via the food chain is one of the greatest public health problems being confronted today. Therefore, we focused on the bacterial safety of fruit, vegetables and sprouts on sale in the Czech Republic. One strain (0.3%) of Salmonella Enteritidis phage type PT8, one strain (0.3%) of MRSA and 17 strains (5.0%) of L. monocytogenes were isolated from a total of 339 collected samples. The most problematic commodities were frozen fruit and vegetables (packed and unpacked) and fresh-cut vegetables. Our findings indicate deficiencies in hygiene practices during harvesting, processing and distribution of these commodities. Although sprouts and berries are the most likely to be contaminated by human pathogens, only two samples were positive for the presence of L. monocytogenes.

• MeSH
• Bacteria izolace a purifikace   MeSH
• bezpečnost potravin * MeSH
• Escherichia coli O157 izolace a purifikace   MeSH
• lidé MeSH
• Listeria monocytogenes izolace a purifikace   MeSH
• methicilin rezistentní Staphylococcus aureus izolace a purifikace   MeSH
• ovoce mikrobiologie   MeSH
• počet mikrobiálních kolonií MeSH
• polymerázová řetězová reakce MeSH
• potravinářská mikrobiologie MeSH
• Salmonella enteritidis izolace a purifikace   MeSH
• semenáček mikrobiologie   MeSH
• shiga-toxigenní Escherichia coli izolace a purifikace   MeSH
• techniky typizace bakterií MeSH
• zelenina mikrobiologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

The occurrence of antimicrobial-resistant bacteria is an important public health issue. The aim of this study was the monitoring of resistant Escherichia coli in raw cow's milk with a focus on the detection of extended-spectrum β-lactamase (ESBL)-producing strains. In total, 263 samples of raw milk from 40 farms were collected and investigated in 2010 to 2013 in the Czech Republic. Detection of E. coli was performed and evaluated according to ISO 16649-2, and antibiotic resistance was screened by the disk diffusion method. The presence of E. coli was detected in 243 (92.4%) samples. In total, 270 isolates were obtained. Resistance to β-lactam (31.8%) and tetracycline (13.0%) antibiotics was detected most often and also multiresistant strains (5.5%) were observed. E. coli isolates found to be resistant to β-lactam, tetracycline, and quinolone antibiotics were assayed by PCR to detect selected genes encoding those resistance mechanisms. In isolates in which any bla genes were detected, a double-disk synergy test was performed. ESBL production was confirmed in 2 (0.7%) isolates. The genetic analysis identified the presence of the blaCTX-M gene and other resistance genes (tet(B) and qnrB). Both ESBL-positive isolates originated from the same farm and had an identical pulsed-field gel electrophoresis profile. The findings of our study indicate that milk can be a reservoir of bacteria carrying resistance genes with a potential for spreading through the food chain.

• MeSH
• antibakteriální látky farmakologie   MeSH
• beta-laktamasy biosyntéza   genetika   MeSH
• Escherichia coli účinky léků   enzymologie   genetika   izolace a purifikace   MeSH
• mléko mikrobiologie   MeSH
• mnohočetná bakteriální léková rezistence genetika   MeSH
• polymerázová řetězová reakce MeSH
• proteiny z Escherichia coli genetika   MeSH
• pulzní gelová elektroforéza MeSH
• skot MeSH
• syrová strava mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH

A large epidemic caused by shigatoxigenic Escherichia coli (E. coli) in spring 2011 in Germany resulted in reduction of trust in the health safety of raw vegetables and sprouted seeds. This study focused on the detection and characterization of E. coli in raw vegetables and sprouted seeds sold in the Czech Republic. Out of 91 samples, 24 (26.4%) were positive for the presence of E. coli. Resistance to antimicrobial agents was determined by the disk diffusion method and E-test. Polymerase chain reaction was used for the detection of selected genes encoding virulence--eaeA, hly, stx1, and stx2 and genes encoding resistance to tetracycline--tet(A), tet(B), tet(C), and tet(G) and to β-lactams--blaTEM, blaSHV, and blaCTX. The blaTEM gene was detected in two isolates, the tet(B) gene in three and tet(A) in one isolate. No hly, stx1, or stx2 genes were present, but the eaeA gene was found in three (11.1%) isolates from imported vegetables. These isolates can be considered as potentially enteropathogenic. Results of this study show that raw vegetables and sprouted seeds sold in the retail market can represent a potential risk for consumers.

• MeSH
• bakteriální geny * MeSH
• Escherichia coli genetika   izolace a purifikace   MeSH
• mikrobiální testy citlivosti MeSH
• polymerázová řetězová reakce MeSH
• potravinářská mikrobiologie MeSH
• proteiny z Escherichia coli genetika   MeSH
• pulzní gelová elektroforéza MeSH
• rezistence na tetracyklin genetika   MeSH
• semena rostlinná mikrobiologie   MeSH
• virulence genetika   MeSH
• zásobování potravinami MeSH
• zelenina mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH