Antibiotic susceptibility and prevalence of foodborne pathogens in poultry meat in Romania.

INTRODUCTION: The occurrence of pathogenic strains in poultry meat is of growing concern in Romania. Another problem found on a global level is the continuous increase of antimicrobial resistance in bacteria isolated from food. This study aimed to evaluate the prevalence of pathogenic bacteria in poultry carcasses obtained in Romania in 2012-2013 and to reveal the most prevalent patterns of antimicrobial resistance in the isolated strains. METHODOLOGY: A total of 144 broiler chicken carcasses were evaluated according to classical microbiological methods. The DNA was extracted from the bacterial colonies and the resistance genes were identified by PCR. RESULTS: In 2012, 47.2% of the samples revealed at least one of the following bacteria: Campylobacter jejuni (9.72%; n = 7), Salmonella enterica serotype Enteritidis (4.17%; n = 3), Listeria monocytogenes (15.28%; n = 11), and Escherichia coli (16.67%; n = 12). In 2013, the number of positive samples of pathogenic bacteria decreased, although Campylobacter jejuni was isolated in a higher percentage (20.8% vs. 9.72%). The percentage of multidrug-resistant (MDR) bacteria was high (23%); the most prevalent pattern included resistance to tetracycline, sulfonamides, and quinolones/fluoroquinolones. All the resistant Salmonella and E. coli strains were tested for the presence of characteristic resistance genes (Kn, bla(TEM), tetA, tetB, tetG, DfrIa, aadA1a, Sul) and revealed that these isolates represent an important reservoir in the spread of this phenomenon. CONCLUSIONS: Our findings suggest that Romania urgently needs an integrated surveillance system within the entire chain, for drug-resistant pathogens isolated from poultry meat.

First study of Salmonella in meat in Romania.

INTRODUCTION: The increasing antimicrobial resistance of Salmonella isolates is of major public health concern, but information regarding these aspects is still lacking in Romania. This study focused on a detailed and accurate investigation concerning prevalence, serotypes, and antimicrobial resistance patterns of Salmonella strains, isolated from pork and chicken meat, collected from all regions of Romania in 2011. METHODOLOGY: The research was conducted on 650 samples of chicken and pork meat collected from production units and retail markets located in various regions of Romania. A total of 149 Salmonella isolates were recovered (22.92%), serotyped, confirmed by PCR, and further tested for antimicrobial susceptibility. RESULTS: Thirteen Salmonella serovars were identified; predominant serovars included Infantis, Typhimurium, Derby and Colindale. Multiple resistance was found in 83.22% (n = 124) of the isolates. The isolates were frequently resistant to tetracycline (80.53%), streptomycin (81.21%), sulfamethoxazole (87.25%), nalidixic acid (65.10%), and ciprofloxacin (42.95%). Additionally, a markedly lower resistance rate was observed for ampicillin (20.81%), chloramphenicol (16.78%), and ceftazidime (11.41%). Among 137 resistant Salmonella isolates, 35 different resistance patterns were found. CONCLUSION: A high prevalence of Salmonella spp. and a relatively high resistance rate to multiple antimicrobials was found. This data indicates that chicken and pork meat could constitute a source of human exposure to multidrug-resistant Salmonella and therefore could be considered a potential vehicle of resistant Salmonella foodborne diseases. Further actions are needed to succesfully implement a national surveillance program for better monitoring of these resistant pathogens.

Strain dependent UV degradation of Escherichia coli DNA monitored by Fourier transform infrared spectroscopy.

In this work we present a method for detection of DNA isolated from nonpathogenic Escherichia coli strains, respectively. Untreated and UV irradiated bacterial DNAs were analyzed by FT-IR spectroscopy, to investigate their screening characteristic features and their structural radiotolerance at 253.7nm. FT-IR spectra, providing a high molecular structural information, have been analyzed in the wavenumber range 800-1800cm(-1). FT-IR signatures, spectroscopic band assignments and structural interpretations of these DNAs are reported. Also, UV damage at the DNA molecular level is of interest. Strain dependent UV degradation of DNA from E. coli has been observed. Particularly, alterations in nucleic acid bases, base pairing and base stacking have been found. Also changes in the DNA conformation and deoxyribose were detected. Based on this work, specific E. coli DNA-ligand interactions, drug development and vaccine design for a better understanding of the infection mechanism caused by an interference between pathogenic and nonpathogenic bacteria and for a better control of disease, respectively, might be further investigated using Fourier transform infrared spectroscopy. Besides, understanding the pathways for UV damaged DNA response, like nucleic acids repair mechanisms is appreciated.