Alexandra Tabaran

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 description of plasmid-mediated quinolone resistance determinants and β-lactamase encoding genes in non-typhoidal Salmonella isolated from humans, one companion animal and food in Romania

BackgroundGastroenteritis attributable to Salmonella enterica and the continuous increase in antimicrobial resistance of this gut pathogen, which compromises the use of previously effective treatments, is of great concern for public health. This study was conducted in order to investigate the presence of plasmid-mediated quinolone resistance (PMQR) determinants and β-lactamase-encoding genes, in S.enterica, isolated from humans, one companion animal and food. Moreover, the study aimed to identify potential vehicles of transmission of resistant strains to humans, with focus on food products (meat).MethodsA total of 20 S. enterica isolates recovered from food (chicken and pork meat), one companion animal and humans (stool samples), were examined for their serotype, antimicrobial susceptibility and the presence of PMQR and β-lactamase-encoding genes. Moreover, the genetic relatedness of nine Salmonella Infantis and ten Salmonella Enteritidis isolates was analyzed by pulsed-field gel electrophoresis (PFGE).ResultsAmong all isolates, 15 (75%) were multidrug-resistant (MDR) and the majority of them proved to be resistant to nalidixic acid and fluoroquinolones (FQs) (ciprofloxacin and levofloxacin). Twelve isolates (60%) harboured at least one PMQR gene [qnrA, qnrB, qnrS, aac (6′)-Ib-cr or qepA] while seven isolates (35%) carried at least one β-lactamase-encoding gene (blaTEM, blaPSE-1, blaSHV or blaCTX-M). Moreover, two or more PMQR or β-lactamase-encoding genes co-existed in a single S.enterica isolate. A number of nine Salmonella Infantis, as well as the majority of Salmonella Enteritidis isolates analyzed by PFGE proved to be closely related.ConclusionsThe study demonstrated the co-existence of PMQR and β-lactamase-encoding genes among the Salmonella isolates recovered and confirmed that multiple mechanisms might be involved in the acquisition and spread of resistance determinants. The close genetic relatedness between the clinical and foodborne S. enterica isolates, suggested that chicken meat might be a possible cause of human salmonellosis in our country, during the study period. Results of this study might improve understanding of the antimicrobial resistance mechanisms and transmission dynamics of Salmonella spp. Here, we report for the first time the presence of PMQR and β-lactamase-encoding genes in S. enterica isolates, recovered from humans, one companion animal and food, in Romania.

Concerning Increase in Antimicrobial Resistance in Shiga Toxin-Producing Escherichia coli Isolated from Young Animals during 1980–2016

This study was conducted in order to assess the antimicrobial resistance patterns of E. coli isolated from young animals affected between 1980 and 2016. The selected isolates for this study (n=175) carried stx1/stx2 genes and the most prevalent type of pathogenic E. coli found belonged to serogroup O101, antigen (K99)–F41 positive. All STEC-positive isolates were tested for susceptibility to 11 antimicrobials. Multidrug resistance (MDR) increased from 11% during the 1980s to 40% between 2000 and 2016. Resistance to tetracycline and streptomycin was the most frequent co-resistance phenotype (37%). Co-resistance to tetracycline and sulfonamide was found in 21% of E. coli isolates, while the MDR pattern to tetracycline, sulfonamide, and streptomycin was observed in 12% of the strains tested. Only 8% of isolates were co-resistant to tetracycline, ampicillin, streptomycin, and sulfonamide. The most common resistance genes found were those encoding for tetracycline, sulphonamides, and streptomycin, with 54% (n=95) of the tested isolates containing at least one of the genes encoding tetracycline resistance. A total of 87% of E. coli that tested positive for tetracycline (tetA, tetB, and tetC) and sulphonamide (sul1) resistance genes were isolated between 2000 and 2016. A large number of isolates (n=21) carried int1 and a nucleotide sequence analysis revealed that all class 1 integron gene cassettes carried sul1, tet, and dfrA1 resistance genes. An increase was observed in the level of resistance to antimicrobials in Romania, highlighting the urgent need for a surveillance and prevention system for antimicrobial resistance in livestock in Eastern Europe.

Microbiological Assessment of Raw Meat Used in Fast-Food Products Sold for Public Consumption

Raw meat contains sufficient nutrients to support microbial growth and because of that the proper surveillance of the meat products destined for public consumption is mandatory. The purpose of this study was to conduct a microbiological risk assessment regarding the safety of pork, chicken and beef meat products found in fast –food units from Transylvania area. One hundred and seventy samples of raw meat(n=35) and fried foods made of pork(n=39), chicken(n=45)and beef products(n=51) were purchased randomly from 5 different fast-food units located in the study area.The determination performed in order to assess the safety was the total number of Enterobacteriaceae, evaluation of toxigenic E. coli and Salmonella spp. presence, which is also the parameter requested by the current regulation. The levels of contamination with Enterobacteriaceae that exceeded the current legislation limit were 6/39 (15%), 6/45 (13%) and 5/51 (9%) in cooked pork, chicken and respectively beef meat. Given the similar rate of contaminations among these three categories of food there were no statistical differences noticed (p>0.05). Results showed that in 35 of 170 (20%) collected food samples were found total Enterobacteriaceae count over 3 log CFU/g and 12 of 170 (7%) were found with coliform bacteria. Raw meat destined for fast-food industry can represent a risk for public health if hygiene and refrigerating conditions are not properly monitored.