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- Estabelecimentos de Restauração e Bebidas: estudo sobre a Qualidade do Ar Interior em CozinhasPublication . Ferreira, Daniela; Rebelo, Andreia; Santos, Joana; Sousa, Vanessa; Vieira Da Silva, ManuelaO sector da Restauração e Hotelaria encontra-se em constante expansão e representa uma importante fonte de emprego no sector dos serviços, empregando cerca de 7,8 milhões de pessoas na União Europeia. As condições de trabalho deste sector apresentam vários riscos associados ao trabalho fisicamente exigente, exposição a elevados níveis de ruído, trabalho realizado em ambientes quentes ou frios, quedas, cortes, queimaduras, exposição a substâncias perigosas e riscos psicossociais, relacionados com as condições ergonómicas, exigências das funções, horários de trabalho e autonomia, entre outros (AESST, 2008). As áreas de fabrico são espaços onde devem ser considerados um conjunto de requisitos que minimizem a contaminação dos alimentos e garantam condições adequadas de higiene e segurança no trabalho (Afonso & Silva, 2009). No âmbito da higiene e segurança no trabalho existe legislação nacional aplicável a este sector com o objectivo de eliminar/minimizar a exposição a riscos profissionais, melhorando as condições estruturais e de funcionamento destes espaços, como a Portaria n.º 987/93, de 6 de Outubro e o Decreto-Lei n.º 243/86, de 20 de Agosto.
- Exposição ocupacional a agentes biológicos na manutenção de infraestruturas de saneamentoPublication . Silva, Bibiana; Rebelo, Andreia; Oliveira, Rui; Baptista, João; Santos, JoanaThe maintenance and cleaning of sanitation infrastructures are characterised by workers’ exposure to potentially hazardous biological agents. Thus, the aim of this study was to evaluate workers' occupational exposure to total mesophilic microorganisms' concentrations at 37ºC, Gram-negative bacteria and fungi in Wastewater Lifting Plants (WLP) and relate them with the critical points associated with the tasks developed in these infrastructures. Samples were collected from the air, hands and nose. Air samples were collected in three different WLP's (A, B and C) in two seasons - winter and spring - at two sampling points, considering infrastructure characteristics. Microbiological analysis of the hands and upper respiratory tract (nose) of the workers was done using the swab technique. The perception of WLP workers about their general state of health was also analysed using Portuguese Version of short form-12 (SF-12) health status questionnaire. The highest concentrations of mesophilic microorganisms at 37° C, Gram-negative bactéria and fungi were, respectively, 1.95x103 CFU/m3, 1.69x103 CFU/m3 and 1.51x103 CFU/m3. In the hands and nose the microorganisms’ concentrations ranged, respectively between 0 to 2x106 CFU/ml and 0 to 2.8x104 CFU/ml. In general, workers classified their health as reasonable. These results demonstrated that measures such as the use of suction pipes with diameters exceeding or construction of vertical slugged reservoirs, as essential for the control of exposure to biological agents. Future research should be developed to improve risk assessment methodologies and air sampling methods in this type of work environment.
- Assessment of antimicrobial resistance spread in surface aquatic systems: a study of four rivers in north PortugalPublication . Matos, Cátia; Duarte, Bárbara; Rebelo, Andreia; Lopes, Diana; Freitas, Ana R.; Valente, Margarida; Tavares, Carolina; Rodrigues, Juliana; Peixe, Luísa; Antunes, Patrícia; Novais, CarlaAntimicrobial resistance (AMR) spread in surface water systems, providing water for drinking or for recreational activities, can have serious implications to human, animal and environmental health. The standard criteria to assess water quality are based in the absence of specific bacteria, and do not include AMR study. Here we evaluate the spread of AMR bacteria in rivers of North Portugal under diverse anthropogenic activities.
- Diversity of metal and antibiotic resistance genes in Enterococcus spp. from the last century reflects multiple pollution and genetic exchange among phyla from overlapping ecosystemsPublication . Rebelo, Andreia; Mourão, Joana; Freitas, Ana R.; Duarte, Bárbara; Silveira, Eduarda; Sanchez-Valenzuela, António; Almeida, Agostinho; Baqueroik, Fernando; Coqueik, Teresa M.; Peixe, Luísa; Antunes, Patrícia; Novais, CarlaArsenic (As), mercury (Hg), and copper (Cu) are among the major historical and contemporary metal pollutants linked to global anthropogenic activities. Enterococcus have been considered indicators of fecal pollution and antibiotic resistance for years, but its largely underexplored metallome precludes understanding their role as metal pollution bioindicators as well. Our goal was to determine the occurrence, diversity, and phenotypes associated with known acquired genes/operons conferring tolerance to As, Hg or Cu among Enterococcus and to identify their genetic context (381 field isolates from diverse epidemiological and genetic backgrounds; 3547 enterococcal genomes available in databases representing a time span during 1900–2019). Genes conferring tolerance to As (arsA), Hg (merA) or Cu (tcrB) were used as biomarkers of widespread metal tolerance operons. Different variants of metal tolerance (MeT) genes (13 arsA, 6 merA, 1 tcrB) were more commonly recovered from the food-chain (arsA, tcrB) or humans (merA), and were shared with 49 other bacterial taxa. Comparative genomics analysis revealed that MeT genes occurred in heterogeneous operons, at least since the 1900s, with an increasing accretion of antibiotic resistance genes since the 1960's, reflecting diverse antimicrobial pollution. Multiple MeT genes were co-located on the chromosome or conjugative plasmids flanked by elements with high potential for recombination, often along with antibiotic resistance genes. Phenotypic analysis of some isolates carrying MeT genes revealed up to 128× fold increase in the minimum inhibitory concentrations to metals. The main distribution of functional MeT genes among Enterococcus faecium and Enterococcus faecalis from different sources, time spans, and clonal lineages, and their ability to acquire diverse genes from multiple taxa bacterial communities places these species as good candidates to be used as model organisms in future projects aiming at the identification and quantification of bioindicators of metal polluted environments by anthropogenic activities.
- Distribution of Arsenic Tolerance Genes (arsA) among Enterococcus spp. from different sources, continents and timeframes (<1906-2015).Publication . Rebelo, Andreia; Mourão, Joana; Freitas, Ana; Coque, Teresa; Almeida, Agostinho; Peixe, Luísa; Antunes, Patrícia; Novais, CarlaSuccessful bacteria accumulate different genetic features shaping their evolution and fitness to diverse environments/hosts. Arsenic-compounds are widespread in nature and possibly contribute to selection of particular strains. The aim of this study was to evaluate the dispersion of arsA genes among Enterococcus from different sources, continents and timeframes. The arsA genes (coding for arsenical-pump-driving-ATPases) were searched in GenBank Enterococcus genomes and used to construct a maximum-likelihood phylogenetic-tree. A PCR scheme+sequencing was developed to detect arsA alleles from all phylogenetic subgroups identified among 333 isolates (Portugal; human/animal/environment/food; 1996-2012)1. Na2HAsO4 susceptibility was evaluated by agar dilution (0,25 to 128mM; n=143 isolates).
- Legionella spp. risk assesment in residential care homes for elderly people: development of a risk matrixPublication . Silva, Cristiana; Rebelo, Andreia; Silva, Manuela V.The genus Legionella spp. includes a group of pathogenic bacteria, which are frequently associated with natural or artificial freshwater environments, but usually in insufficient levels to cause infection. However, in the case of the presence of Legionella pneumophila constitute always a public health concern. The risk of occurrence of Legionella spp., especially in places on the presence of human risk groups and workers, such as residential structures for the elderly, represent a relevant activity for prevention. This work aimed to develop a risk instrument to assess the presence of Legionella spp. in building structures and equipment’s. The methodology was based on previous knowledge acquired within the context of health and safety, the simplified W.T. Fine method and the methodology developed by the DGS of Portugal for the management of biological risks. From the risk assessment carried out, it was possible to identify potential non-compliance instances associated with the different equipment and characteristics of the facilities, such as “Inadequate hygiene/cleaning”, “Poor condition (e.g. filters, pipes, taps)” and “Water Stagnation”, being that “Taps/Showers” are those with the highest level of risk. The risk analysis and categorization proves to be an important tool used to prevention by the early risk identification and measures to avoid the occurrence of Legionella spp. in residence care homes buildings.
- High rates of ampicillin multidrug-resistant Enterococcus faecium in chicken meat from PortugalPublication . Novais, Carla; Freitas, Ana Raquel; Ferreira, Carolina; Scholes, Christopher; Duarte, Barbara; Ribeiro, Sofia; Mourão, Joana Vanessa Cordeiro Melro; Rebelo, Andreia; Antunes, Patrícia; Peixe, Luísa Maria VieiraResistance to ampici lin-AmpR is associated with Enterococcus faecium-Efm from hospitalizedhumans (clade-A1) and at lesser extent with community-based isolates (clade-A2: human and animal strains; clade-B: human-commensal strains). Recently, AmpR combined with specific putative virulence factors were proposed as molecular markers of Efm linked to human infections, which can have an impact in Efm risk assessment in different public health contexts (PMID:29519512). Here we evaluated the occurrence of AmpR-Efm with potential public health impact in chicken-meat samples.
- Decoding Klebsiella pneumoniae in poultry chain: Unveiling genetic landscape, antibiotic resistance, and biocide tolerance in non-clinical reservoirsPublication . Mourão, Joana; Magalhães, Mafalda; Ribeiro-Almeida, Marisa; Rebelo, Andreia; Novais, Carla; Peixe, Luísa; Novais, Ângela; Antunes, PatríciaThe rise of antibiotic resistance in the food chain is influenced by the use of antimicrobial agents, such as antibiotics, metals, and biocides, throughout the entire farm-to-fork continuum. Besides, non-clinical reservoirs potentially contribute to the transmission of critical pathogens such as multidrug-resistant (MDR) Klebsiella pneumoniae. However, limited knowledge exists about the population structure and genomic diversity of K. pneumoniae circulating in conventional poultry production. We conducted a comprehensive characterization of K. pneumoniae across the whole chicken production chain (flocks/environment/meat, 2019-2022), exploring factors beyond antibiotics, like copper and quaternary ammonium compounds (QACs). Clonal diversity and adaptive features of K. pneumoniae were characterized through cultural, molecular (FT-IR), and whole-genome-sequencing (WGS) approaches. All except one flock were positive for K. pneumoniae with a significant increase (p < 0.05) from early to pre-slaughter stages, most persisting in chicken meat batches. Colistin-resistant K. pneumoniae rates were low (4%), while most samples carried MDR strains (67%) and copper-tolerant isolates (63%; sil+pco clusters; MICCuSO4≥16mM), particularly at pre-slaughter. Benzalkonium chloride consistently exhibited activity in K. pneumoniae (MIC/MBC range=4-64mg/L) from diverse and representative strains independently of the presence/absence of genes linked to QACs tolerance. A polyclonal K. pneumoniae population, discriminated by FT-IR and WGS, included various lineages dispersed throughout the chicken’s lifecycle at the farm (ST29-KL124, ST11-KL106, ST15-KL19, ST1228-KL38), until the meat (ST1-KL19, ST11-KL111, ST6405-KL109, and ST6406-CG147-KL111), or over years (ST631-49 KL109, ST6651-KL107, ST6406-CG147-KL111). Notably, some lineages were identical to those from human clinical isolates. WGS also revealed F-type multireplicon plasmids carrying sil+pco (copper) co-located with qacEΔ1±qacF (QACs) and antibiotic resistance genes like those disseminated in humans. In conclusion, chicken farms and their derived meat are significant reservoirs for diverse K. pneumoniae clones enriched in antibiotic resistance and metal tolerance genes, some exhibiting genetic similarities with human clinical strains. Further research is imperative to unravel the factors influencing K. pneumoniae persistence and dissemination within poultry production, contributing to improved food safety risk management. This study underscores the significance of understanding the interplay between antimicrobial control strategies and non-clinical sources to effectively address the spread of antimicrobial resistance.
- Unveiling the contribution of ars operon for arsenic tolerance among clinically-relevant Salmonella serotypes/clonesPublication . Mourão, Joana; Rebelo, Andreia; Machado, Jorge; Almeida, Agostinho; Peixe, Luísa; Novais, Carla; Antunes, PatríciaArsenic environmental contamination by anthropogenic activities, including in animal-farming management (e.g. coccidiostatics/pesticides/waste), may represent a long-term selective pressure driving the selection of multidrug-resistant (MDR) emergent Salmonella serotypes/clones. Diverse arsenic tolerance (AsT) mechanisms were described, although dispersion and association with a tolerance phenotype remains unknown in Salmonella. Our objective was to study the occurrence of genes coding for arsenical efflux pumps and their implications in tolerance phenotypes in diverse Salmonella serotypes and clones, including emergent MDR and/or copper/silver tolerant ones. 283 Salmonella isolates (2000-2016; humans/foods/animal/environment) from 57 serotypes (including the most frequent: Enteritidis/n=16; Typhimurium/n=49; 4,[5],12:i:-/n=63; Rissen/n=15) were selected based in PFGE-types and/or STs obtained by MLST and different profiles of antibiotic-resistance or metal-tolerance (Cu/Ag/Hg/Te)1,2. Screening of arsenic tolerance genes, arsB and acr3 (both coding for arsenical pump membrane proteins) was performed by PCR/sequencing. MICNa2HAsO4 were determined in aerobic and anaerobic atmospheres by the agar dilution method.
- Children’s play paints safety – What is the reality in Portuguese schools and at retail stores?Publication . Rebelo, Andreia; Vieira Da Silva, ManuelaChildren’s play paints, an attractive tool for preschool activities, can be classified in artist paints (gouaches, acrylics, watercolors, fingerpaints) and face paints. These products composition is not always known since not all are required to bear their ingredients in the label packaging. The present study aimed to characterize the children’s play paints available in schools and retail stores and also to assess the practices involved in the acquisition, handling and storage of these products by schools and that may have impact on the product quality and safety. For this purpose were studied paints from 8 schools and 7 retail stores from Porto (Portugal), in a total of 17 popular brands. The results shows that the label information differs from product type, taking into account the legal requirements applied to each one (artist paints or face paints). The main hazards stated in the products label are related with the possibility of ingestion of small pieces that are part of the product. Only brands of face paints (60%) mentioned the potential risk to develop allergic reactions or skin irritation problems arising from their application. As regards to school practices, they are aware to the importance in purchasing products suitable for children use however, some of the behaviors during storage and handling of these products may affect their quality and safety.
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