Browsing by Author "Silva, Vanessa"
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- Antimicrobial resistance and clonal lineages of staphylococcus aureus from cattle: a cross-sectional study from the one health perspectivePublication . Silva, Vanessa; Correia, Susana; Rocha, Jaqueline; Manaia, Célia M.; Silva, Adriana; García-Díez, Juan; Pereira, José Eduardo; Semedo-Lemsaddek, Teresa; Igrejas, Gilberto; Poeta, PatríciaStaphylococcus aureus have been progressively identified in farm animals and in humans with direct contact with these animals showing that S. aureus may be a major zoonotic pathogen. Therefore, we aimed to isolate S. aureus from cows, their handlers, and their immediate surroundings, and to investigate the antimicrobial resistance and genetic lineages of the isolates. Mouth and nose swabs of 244 healthy cows (195 Maronesa, 11 Holstein-Friesians, and 28 crossbreeds), 82 farm workers, 53 water and 63 soil samples were collected. Identification of species was carried out by MALDI-TOF MS Biotyper. The presence of antimicrobial resistance genes and virulence factors was assessed based on gene search by PCR. All isolates were typed by multilocus sequence typing and spa-typing. From 442 samples, 33 (13.9%), 24 (29.3%), 1 (2%), and 1 (2%) S. aureus were recovered from cows, farm workers, water, and soil samples, respectively. Most of the isolates showed resistance only to penicillin. S. aureus isolates were ascribed to 17 sequence types (STs) and 26 spa-types. Some clonal lineages were common to both cows and farm workers such as ST30-t9413, ST72-t148, and ST45-t350. Through a One Health approach, this study revealed that there is a great diversity of clonal lineages of S. aureus in cows and their handlers. Furthermore, some S. aureus lineages are common to cows and handlers, which may suggest a possible transmission.
- Comparative genomics insights into clinical or environmental methicillin resistant staphylococcus aureusPublication . Rocha, Jaqueline; Silva, Vanessa; Poeta, Patrícia; Manaia, Célia M.
- Genetic characterization of methicillin-resistant staphylococcus aureus isolates from human bloodstream infections: detection of mlsb resistancePublication . Silva, Vanessa; Hermenegildo, Sara; Ferreira, Catarina; Manaia, Celia M.; Capita, Rosa; Alonso-Calleja, Carlos; Carvalho, Isabel; Pereira, José Eduardo; Maltez, Luís; Capelo, José L.; Igrejas, Gilberto; Poeta, PatriciaIn this study we aimed to characterize antimicrobial resistance in methicillin-resistant Staphylococcus aureus (MRSA) isolated from bloodstream infections as well as the associated genetic lineages of the isolates. Sixteen MRSA isolates were recovered from bacteremia samples from inpatients between 2016 and 2019. The antimicrobial susceptibility of these isolates was tested by the Kirby–Bauer disk diffusion method against 14 antimicrobial agents. To determine the macrolide–lincosamide–streptogramin B (MLSB) resistance phenotype of the isolates, erythromycin-resistant isolates were assessed by double-disk diffusion (D-test). The resistance and virulence genes were screened by polymerase chain reaction (PCR). All isolates were characterized by multilocus sequence typing (MLST), spa typing, staphylococcal chromosomal cassette mec (SCCmec) typing, and accessory gene regulator (agr) typing. Isolates showed resistance to cefoxitin, penicillin, ciprofloxacin, erythromycin, fusidic acid, clindamycin, and aminoglycosides, confirmed by the presence of the blaZ, ermA, ermC, mphC, msrA/B, aac(6’)-Ie-aph(2’’)-Ia, and ant(4’)-Ia genes. Three isolates were Panton–Valentine-leukocidin-positive. Most strains (n = 12) presented an inducible MLSB phenotype. The isolates were ascribed to eight spa-types (t747, t002, t020, t1084, t008, t10682, t18526, and t1370) and four MLSTs (ST22, ST5, ST105, and ST8). Overall, most (n = 12) MRSA isolates had a multidrug-resistance profile with inducible MLSB phenotypes and belonged to epidemic MRSA clones.
- High frequency of the EMRSA-15 clone (ST22-MRSA-IV) in hospital wastewaterPublication . Silva, Vanessa; Ribeiro, Jessica; Rocha, Jaqueline; Manaia, Célia M.; Silva, Adriana; Pereira, José Eduardo; Maltez, Luís; Capelo, José Luis; Igrejas, Gilberto; Poeta, PatríciaHospital wastewaters often carry multidrug-resistant bacteria and priority pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA). Pathogens and antibiotic resistance genes present in wastewaters may reach the natural environment facilitating their spread. Thus, we aimed to isolate MRSA from wastewater of 3 hospitals located in the north of Portugal and to characterize the isolates regarding the antimicrobial resistance and genetic lineages. A total of 96 wastewater samples were collected over six months. The water was filtered, and the filtration membrane was immersed in BHI broth supplemented with 6.5% of NaCl and incubated. The inoculum was streaked in ORSAB agar plates for MRSA isolation. The isolates susceptibility testing was performed against 14 antimicrobial agents. The presence of resistance and virulence genes was accessed by PCR. Molecular typing was performed in all isolates. From the 96 samples, 28 (29.2%) were MRSA-positive. Most isolates had a multidrug-resistant profile and carried the mecA, blaZ, aac(6′)-Ie-aph(2′′)-Ia, aph(3′)-IIIa, ermA, ermB, ermC, tetL, tetM, dfrA dfrG and catpC221 genes. Most of the isolates were ascribed to the immune evasion cluster (IEC) type B. The isolates belonged to ST22-IV, ST8-IV and ST105-II and spa-types t747, t1302, t19963, t6966, t020, t008 and tOur study shows that MRSA can be found over time in hospital wastewater. The wastewater treatment processes can reduce the MRSA load. The great majority of the isolates belonged to ST22 and spa-type t747 which suggests the fitness of these genetic lineages in hospital effluents.
- One health approach reveals the absence of methicillin-resistant staphylococcus aureus in autochthonous cattle and their environmentsPublication . Correia, Susana; Silva, Vanessa; García-Díez, Juan; Teixeira, Paula; Pimenta, Kevin; Pereira, José E.; Oliveira, Soraia; Rocha, Jaqueline; Manaia, Célia M.; Igrejas, Gilberto; Poeta, PatríciaAntimicrobial resistance represents one of the greatest challenges of the twenty-first century, and it is globally recognized that addressing this problem requires a concerted One Health approach involving humans, animals, and the environment. Methicillin-resistant Staphylococcus aureus (MRSA) currently represents a global burden; it is resistant to almost all beta-lactams and some MRSA strains are highly multiresistant. S. aureus infection in cattle results in major economic losses in the food industry. Moreover, cases of livestock-associated MRSA strains responsible for invasive life-threatening infections have been reported among human patients in contact with infected or colonized animals. The autochthonous Maronesa cattle breed is a threatened rustic traditional Portuguese breed of mountain cattle of high importance for the Vila Real region. It has been used for centuries as motive power in all kinds of agricultural work and also for meat production, which is its current dominant use and the main source of economic value, being the Maronesa meat commercialized with PDO - Protected Designation of Origin. This study aimed to determine the prevalence and transmission of MRSA in cattle of the Maronesa breed, through a concerted One Health approach comprising human, water, and soil samples of the animals’ handlers and environments. In a total of 195, 63, 40, and 43 cattle, human, water, and soil samples screened in selective ORSAB media supplemented with 2 mg/L oxacillin; only one human sample harbored a MRSA isolate which was ascribed to spa-type t9413 and to ST30, one of the most common genetic lineages associated with community-acquired MRSA. Considering the increasing reports of MRSA isolation from cattle and handlers in Europe, the absence of this major human and animal pathogen in Maronesa cattle and their production systems represents a serendipitous result, valuing this important autochthonous breed. To our knowledge, this is the first study to determine MRSA prevalence and transmission in Maronesa cattle. Through a concerted One Health approach, this study revealed that the Maronesa cattle and their surrounding environments do not represent reservoirs for Methicillin-resistant Staphylococcus aureus.
- Searching for links between environmental and clinical mecA+ Staphylococcus aureus: a comparative genomics studyPublication . Rocha, Jaqueline; Silva, Vanessa; Poeta, Patrícia; Botelho, João; Manaia, Célia M.Staphylococcus aureus integrate the list of highly virulent and antibiotic resistant pathogens, mainly due to the mecA gene, associated with methicillin resistance. Given the ubiquity of this species, the aim of this study was to investigate whether closely related mecA+ S. aureus found in the environment can be also thrive as clinical isolates and if the respective accessory genome may suggest bacterial adaptation. The genomes of environmental (water, animal facilities, food products, n = 111) isolates were compared with closely related genomes of clinical origin (human patients, n = 103). These genomes, available in the public database NCBI, were analysed for phylogeny, accessory genome, and presence of selected clinically relevant genes (n = 104). The genomes of environmental isolates belonged to 18 multi-locus sequence types (MLSTs), 11 of which also included clinical genomes, a result confirmed based on core-genome analysis. Genes significantly (p ≤ 0.05) more frequent among environmental genomes were related with resistance to β-lactams (blaI, blaPCI), aminoglycosides (ant(6)-Ia), macrolides (mph(C), erm(B)), enterotoxins (seg, sei, sem, sen, seo, seu) and serine protease functions (splB), among others. Genes significantly more frequent among clinical genomes were associated with resistance to macrolides (erm(C)), phenicols (fexA), fosfomycin (murA), the leucocidin virulence gene (lukS-PV), and serine protease functions (splA, splE). It is suggested that mecA+ S. aureus can be exchanged between clinical and environmental settings, with accessory traits (particularly antibiotic resistance, virulence and stress response) possibly being associated with the habitat. The interplay between phylogeny and accessory genome is an interesting contribution to better understanding the ecology and evolution of mecA+ S. aureus.
- Sintomatologia depressiva no termo da gestação, em mulheres de baixo riscoPublication . Silva, Vanessa; Ferreira, Cátia; Basílio, Adriana; Ferreira, Ana Beatriz; Maia, Berta; Miguelote, RuiObjetivos: Calcular a prevalência de sintomatologia depressiva pré-natal em grávidas de baixo risco, no termo da gestação, avaliar seus preditores e desfechos materno-fetais. Para tal, avaliar-se-á a aplicabilidade da Escala de Rastreio de Depressão Pós-Parto (PDSS 24) nessa fase da gravidez. Métodos: A PDSS 24 e um questionário sociodemográfico, psicossocial e médico (antecedentes obstétricos e patológicos) foram autoaplicados a 403 grávidas (37-40 semanas de gestação), com idade média de 30,5 anos (DP = 4,67). Por meio do processo clínico, foram recolhidos dados de resultados materno-fetais. Resultados: A PDSS 24 possui propriedades psicométricas adequadas para a deteção de sintomatologia depressiva pré-natal. A prevalência de sintomatologia depressiva pré-natal foi de 41,7%. Grávidas com níveis de escolaridade inferiores, não casadas, cuja gravidez não foi planejada e com antecedentes de acontecimentos de vida significativos apresentam risco duas vezes superior de sintomatologia depressiva no período pré-natal. Grávidas cujo apoio social percebido ao longo da gravidez não correspondeu ao desejado e com história prévia de depressão apresentam cerca de três vezes maior risco sintomatologia depressiva no período pré-natal. Para desfechos materno-fetais (pré-eclâmpsia, restrição de crescimento fetal, Apgar 1º/5º minuto, tipo de parto, percentil de peso, oligoâminos e necessidade de cuidados intensivos), as diferenças foram não significativas. Conclusão: O rastreio da depressão pré-natal deve ser realizado na gravidez. Porém, no termo da gestação o uso da PDSS 24 como ferramenta de deteção de sintomatologia depressiva deve ser feito com cautela. A elevada prevalência de sintomas relacionados com o sono nessa fase da gestação pode conduzir ao sobre diagnóstico, usando a PDSS 24.