Percorrer por autor "Peixe, Luísa"
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- Carne de aves importada como fonte de transmissão de Salmonella Heidelberg e S. Minnesota resistentes a cefalosporinas de espectro alargadoPublication . Campos, Joana; Mourão, Joana; Silveira, Leonor; Saraiva, Margarida; Belo Correia, Cristina; Maçãs, Ana Paula; Peixe, Luísa; Antunes, PatríciaSalmonella com resistência a cefalosporinas de espectro alargado (ESC), antibióticos de primeira linha para a salmonelose invasiva em humanos, têm sido descritas raramente na União Europeia (UE), incluindo em Portugal. No entanto, a crescente comercialização de carne de aves procedente de países fora do espaço UE tem sido referida como uma potencial fonte de Salmonella portadoras de genes de resistência a ESC. Neste estudo procedeu-se à caracterização fenotípica e genotípica da resistência a ESC, bem como à análise da relação clonal de Salmonella obtidas de amostras de carne de aves no âmbito do controlo oficial 2014 e 2015.
- Clinical Salmonella Typhimurium ST34 with metal tolerance genes and an IncHI2 plasmid carrying oqxAB-aac(6')-Ib-cr from EuropePublication . Campos, Joana; Mourão, Joana; Marçal, Sara; Machado, Jorge; Novais, Carla; Peixe, Luísa; Antunes, PatríciaFluoroquinolones are critical antibiotics for treating severe Salmonella infections, and the widespread of resistant isolates included in diverse epidemiological scenarios and carrying plasmid-mediated quinolone resistance (PMQR) is a global threat. Among PMQR mechanisms, those encoded by oqxAB and aac(6′)-Ib-cr genes are of special concern as they also confer reduced susceptibility to other antibiotics (oqxAB: chloramphenicol, trimethoprim, olaquindox; aac(6′)-Ib-cr: aminoglycosides) and biocides [oqxAB: quaternary ammonium compounds (QACs)].2,3 Although oqxAB ± aac(6′)-Ib-cr are prevalent and widespread in Asia, where olaquindox is still widely used in animal production, they remain scarce in Europe. Here we describe the molecular characterization of clinical ciprofloxacin-resistant Salmonella enterica Typhimurium with concomitant presence of oqxAB and aac(6′)-Ib-cr recovered for the first time in Europe.
- Clinically relevant multidrug resistant Salmonella enterica in swine and meat handlers at the abattoirPublication . Gomes-Neves, Eduarda; Antunes, Patrícia; Manageiro, Vera; Gärtner, Fátima; Caniça, Manuela; Correia da Costa, José Manuel; Peixe, LuísaThe presence of multidrug resistant (MDR) Salmonella serotypes in slaughtered swine, carcasses, meat and meat handlers is scarcely evaluated. Recently we demonstrated that diverse Salmonella serotypes are frequently present in swine, pork meat and carcasses, and meat handlers at Portuguese abattoirs. Here we have characterized their antibiotic resistance phenotypes and genotypes, helping elucidate the flow of MDR Salmonella in the food chain. Testing 60 Salmonella isolates from different serotypes, the highest frequencies of resistance were observed for tetracycline (T) [70% (n = 42/60), tet(A)/tet(B)/tet(G)], streptomycin (S) [63% (n = 38/60), aadA2/strA/strB], sulfamethoxazole (Sul) [62% (n = 37/60), sul1/sul2/sul3] and ampicillin (A) [57% (n = 34/60), blaPSE-1/blaTEM]. Thirty-seven percent (n = 22/60) carried class 1 integrons and multidrug resistance was frequently observed (63% n = 38/60), including those serotypes common to human infections [S. Typhimurium 78% n = 25/32; S. 4,[5],12:i:- 67% n = 2/3; S. Rissen 75% (n = 3/4); S. London 67% n = 2/3; S. Derby 55%; n = 6/11)]. The emergent S. 4,[5],12:i:- isolates were mostly characterized by ASSuT phenotype [blaTEM/strA-strB/sul2/tet(B)], typical of the European clone, while for the first time the ST phenotype [strA-strB-tet(A)-tet(B)] was also observed. Moreover, we report a first finding of a MDR phenotype in S. London [ANSSuT; blaTEM-strA-strB-sul2-tet(A)]. Our findings suggest that the abattoir environment and the slaughter operations seem not only to harbor MDR serotypes that originated in the pig reservoir, but also propagate them through cross-contamination processes, involving meat handlers. The present study suggests a probable relationship between swine and human salmonellosis throughout the food chain, which is of interest for epidemiological, animal health and public health purposes.
- Genomic diversity of Enterobacteriaceae on food-processing surfaces: an overlooked non-clinical setting with public health implicationsPublication . Peixoto, Andreia; Nova, Lúcia; Mourão, Joana; Matos, Cátia; Santos, Susana; Rodrigues, João; Saraiva, Margarida; Correia, Cristina Belo; Batista, Rita; Peixe, Luísa; Novais, Carla; Antunes, PatríciaBacterial hazards on contaminated surfaces in food-processing environments pose significant food safety risks. Hygiene monitoring of surfaces in direct or indirect contact with food typically relies on a limited set of bacterial indicators, such as Enterobacteriaceae counts. However, their genomic diversity remains poorly characterised. The aim of this study was to provide a comprehensive genomic characterisation of Enterobacteriaceae recovered from food-contact surfaces after cleaning and disinfection with biocides in foodservice units. Diverse strains were identified, with some STs shared across samples and/or foodservices. - A diverse Enterobacteriaceae population persists on food-contact surfaces even after cleaning and disinfection with biocides, with evidence of cross-contamination. - These surfaces represent critical points of contact for strains that are genetically similar to those circulating in food, environment, and human clinical sources, including strains carrying clinically relevant AMR genes. - Further research is needed to understand the factors driving their persistence and dissemination in foodservice environments, aiming to enhance food safety risk management protocols and protect public health.
- Imported poultry meat as a source of extended-spectrum cephalosporin-resistant CMY-2-producing Salmonella Heidelberg and Salmonella Minnesota in the European Union, 2014-2015Publication . Campos, Joana; Mourão, Joana; Silveira, Leonor; Saraiva, Margarida; Correia, Cristina Belo; Maçãs, Ana Paula; Peixe, Luísa; Antunes, PatríciaExtended-spectrum cephalosporin (ESC)-resistant Salmonella have been described at a low level in the EU, nevertheless the increasing importation of poultry meat could be an important source of epidemic strains carrying ESC resistance genes. This study evaluated ESC resistance and its genetic platform among Salmonella isolates from poultry meat products imported into Portugal as well as clonal relatedness of the isolates. All Salmonella isolates recovered from samples of fresh meat destined for import into the EU in the scope of Portuguese official border control (2014-2015) were studied. Antibiotic susceptibility and β-lactamase production was determined by disk diffusion/microdilution. Molecular studies included detection of genes encoding acquired AmpC and extended-spectrum β-lactamases, plasmid-mediated quinolone resistance and other antibiotic resistance genes by PCR/sequencing, and clonality by MLST and XbaI-PFGE. Plasmid characterisation was assessed by conjugation assays, replicon typing (PCR-PBRT/pMLST) and hybridisation experiments (I-CeuI/S1-PFGE nuclease). Isolates belonged to Salmonella Heidelberg (n = 6; ST15/eBG26) and Salmonella Minnesota (n = 1; ST548/eBG77) and presented multidrug-resistant profiles, including to ESCs and/or fluoroquinolones. All but one carried blaCMY-2, located on two epidemic plasmids, IncA/C (ST2, n = 5) or transferable IncI1 (ST12, n = 1). Salmonella Heidelberg was associated with five PFGE types, including one similar to an American epidemic clone. This study reveals imported poultry products as a source of uncommon and/or invasive ESC-resistant Salmonella strains in the EU. The increase of clinically relevant poultry-related serotypes in Europe must be taken into account in the current monitoring of antibiotic resistance trends and in re-evaluation of food regulations.
- P-262 - Extended-Spectrum Cephalosporin-Resistant CMY-2-Producing Salmonella Heidelberg and S. Minnesota in Poultry Meat Imported into the European UnionPublication . Campos, Joana; Mourão, Joana; Silveira, Leonor; Saraiva, Margarida; Belo Correia, Cristina; Maçãs, Ana Paula; Peixe, Luísa; Antunes, PatríciaExtended-spectrum cephalosporin-resistant (ESC-R) Salmonella has been described at low level in EU, including in Portugal. Nevertheless, the increasing poultry meat trade involving countries with different animal production practices could be an important source of epidemic clones carrying ESC-R genes. In this study phenotypic and genotypic characterization of resistance to ESC was carried out, as well as the clonal relatedness analysis of Salmonella obtained from poultry meat samples imported into Portugal in the scope of official border control between 2014 and 2015.
- Surface hygiene in food environments: challenges with biocide efficacy and bioindicatorsPublication . Peixoto, Andreia; Matos, Cátia; Santos, Susana; Rodrigues, João; Saraiva, Margarida; Belo Correia, Cristina; Batista, Rita; Peixe, Luísa; Novais, Carla; Antunes, PatríciaThe presence of bacterial hazards on contaminated surfaces in food-processing environments poses significant food safety risks. Monitoring and hygiene verification of surfaces in direct or indirect contact with food remains a top priority for food business operators. Sanitation uses antimicrobial compounds, biocides (disinfectants/antiseptics), whose effectiveness on surface microbiota depends on microorganisms’ susceptibility and factors such as concentration and contact time. The aim of this stydy was to assess the post-disinfection occurrence and diversity of hygiene indicator bacteria on kitchen surfaces of Portuguese foodservice facilities and correlate their presence with biocide usage. Despite recommended biocide use, poor hygiene of surfaces in direct or indirect contact with food was observed. The presence of diverse, potentially pathogenic and recurrent bacterial species suggests persistence, reintroduction, and/or cross-contamination. Identifying phenotypic and genetic markers of persistence, including biocide susceptibility, is crucial for developing real-time hygiene bioindicators and ensuring food safety.
- Tolerance to multiple metal stressors in emerging non-typhoidal MDR Salmonella serotypes: a relevant role for copper in anaerobic conditionsPublication . Mourão, Joana; Marçal, Sara; Ramos, Paula; Campos, Joana; Machado, Jorge; Peixe, Luísa; Novais, Carla; Antunes, PatríciaObjectives: Factors driving the expansion of particular MDR Salmonella serotypes/clones are not completely understood. We assessed if emergent MDR Salmonella serotypes/clones were more enriched in metal tolerance genes (e.g. to Cu/Ag) than other less frequent ones, as an additional feature to survive in environments contaminated with metals. Methods: Metal (Cu pco/Ag,Cu sil/Hg mer/As ars/Te ter) tolerance genes screening (PCR/sequencing), MICs of CuSO4/AgNO3 (aerobiosis/anaerobiosis), genetic element characterization (S1/I-CeuI PFGE) and conjugation assays were performed in a well-characterized Salmonella collection (n = 275 isolates; 2000–14; 49 serotypes/clones). Results The sil ± pco genes were detected in 37% of isolates from diverse serotypes, mainly in emergent Rissen/ST469 and Typhimurium/ST34 European clone (100%), which are mostly associated with pig settings where Cu is highly used. These genes were frequently co-located with merA ± terF and/or antibiotic resistance genes in plasmids (100–270 kb; IncHI2/IncHI1/IncN/IncFIIA; mostly transferable by conjugation) or in the chromosome. Most sil ± pco+ isolates (77%) were MDR contrasting with sil ± pco− ones (48%). The sil ± pco+ isolates presented significantly higher MICCuSO4 under anaerobiosis (MIC50/MIC90 = 28/32 mM) and MICAgNO3 after previous Ag contact (MIC50/MIC90 > 3 mM) than sil− ones (MIC50/MIC90 = 2/8 mM to CuSO4; MIC50/MIC90 = 0.125/0.16 mM to AgNO3). Use of these modified methodological approaches allowed the establishment of CuSO4/AgNO3 tolerance cut-offs to differentiate sil+ and sil− isolates, here firstly proposed. Conclusions: This study demonstrates that acquisition of Cu/Ag tolerance genes (sil/pco genes) might contribute to the emergence of particular clinically relevant MDR Salmonella serotypes/clones by facilitating their survival in diverse metal-contaminated settings, particularly in pig production. Assessment of control measures for the use and/or accumulation of metals in diverse environments are needed to prevent a wider expansion of such strains or the emergence of new ones.