Browsing by Author "Rodrigues, João Carlos"
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- Adenoid bacterial colonization in a paediatric populationPublication . Subtil, João; Rodrigues, João Carlos; Reis, Lúcia; Freitas, Luís; Filipe, Joana; Santos, Alberto; Macor, Carlos; Duarte, Aida; Jordao, LuisaAdenoids play a key role in both respiratory and ear infection in children. It has also been shown that adenoidectomy improves these symptoms in this population. The main goal of the present study was to evaluate adenoid bacterial colonization and document a possible relation with infectious respiratory disease. A prospective observational study was designed to evaluate the proposed hypothesis in a paediatric population submitted to adenoidectomy by either infectious or non-infectious indications and compare these two cohorts. A total of 62 patients with ages ranging from 1 to 12 years old were enrolled in the study. Adenoid surface, adenoid core and middle meatus microbiota were compared. A close association between adenoid colonization and nasal infection was found, supporting that adenoids may function as bacterial reservoir for upper airway infection. The obtained results also contribute to explain the success of adenoidectomy in patients with infectious indications.
- Assessment of the Transmission Dynamics of Clostridioides difficile in a Farm Environment Reveals the Presence of a New Toxigenic Strain Connected to Swine ProductionPublication . Alves, Frederico; Nunes, Alexandra; Castro, Rita; Sequeira, António; Moreira, Olga; Matias, Rui; Rodrigues, João Carlos; Silveira, Leonor; Gomes, João Paulo; Oleastro, MónicaThe recent increase in community-acquired Clostridioides difficile infections discloses the shift in this bacterium epidemiology. This study aimed at establishing a transmission network involving One Health components, as well as assessing the zoonotic potential and genomic features of dominant clones. Samples were collected from different compartments of animal, human and environmental origin, from an animal production unit. C. difficile isolates were characterized for toxigenic profile by multiplex-PCR, while genetic diversity was evaluated by PCR-ribotyping and whole genome-based analysis. The overall C. difficile prevalence was 37.2% (70/188), and included samples from environmental (58.3%, 35/60) and animal (31.5%, 35/111) compartments; human samples (n = 17) taken from healthy workers were negative. A predominant clone from RT033 was found in almost 90% of the positive samples, including samples from all compartments connected to the pig production unit, with core-genome single nucleotide variant (SNV)-based Analysis supporting a clonal transmission between them (mean distance of 0.1 ± 0.1 core-SNVs). The isolates from this clone (herein designated PT RT033) were positive for all C. difficile toxin genes (tcdA, tcdB, cdtA/cdtB). The phyloGenetic positioning of this clone was clearly distinct from the classical RT033 cluster, suggesting a different evolutionary route. This new clone shares genomic features with several RTs from the clade 5 Sequence Type (ST) 11, including a complete pathogenicity locus (PaLoc) that is more similar to the one found in toxigenic strains and contrasting to the less virulent classical RT033 (tcdA-, tcdB-, cdtA + /cdtB +). The presence of a tcdA gene truncated into two ORFs, not previously described, requires further evaluation concerning toxin functionality. We hypothesize that the unique combination of genetic elements found in the PT RT033 clone may contribute to host tropism and environmental dissemination and maintenance. This study constitutes the first report of a toxigenic RT033 clone and adds to the overall knowledge on Clade 5 sequence type 11, considered the C. difficile evolutionary lineage with the highest zoonotic potential. The presence of this clone in all compartments associated with the pig production unit suggests a transmission chain involving these animals and contributes to unveil the role played by animal and environmental reservoirs in this pathogen epidemiology.
- Avaliação do risco para a saúde pública resultante do contacto com águas recreativas e ornamentaisPublication . Fernandes, Vera; Paulino, Sérgio; Costa, Clélia; Rodrigues, João Carlos; Reis, Lúcia; Nogueira, Isabel; Carvalho, Patricia; Duarte, Aida; Jordão, LuísaObjetivos: Este trabalho teve como objetivo caraterizar a população de microrganismos presente em águas recreativas (piscinas) e ornamentais (lagos), bem como avaliar o risco para a saúde pública do contacto com as mesmas.
- Campylobacter em géneros alimentícios: resistências aos antimicrobianos e diversidade genéticaPublication . Santos, Andrea; Rodrigues, João Carlos; Correia, Cristina Belo; Saraiva, Margarida; Oleastro, MónicaEnquadramento: A campilobacteriose é considerada a principal causa de gastroenterite aguda de origem bacteriana em seres humanos, nos países desenvolvidos. Esta infeção está associada principalmente ao consumo e à contaminação cruzada de alimentos, sendo as aves o principal reservatório do agente patogénico. A utilização indiscriminada de antibióticos na produção animal e para fins veterinários, tem contribuído para o aumento do número de estirpes de Campylobacter resistentes aos antimicrobianos, e consequentemente, para o aumento do número de isolados humanos multirresistentes, motivando o estudo e a crescente preocupação das autoridades de saúde, por toda a Europa. Objetivo: Monitorizar a resistência aos antimicrobianos e avaliar a diversidade genética de estirpes de Campylobacter spp., isoladas em géneros alimentícios de produção nacional. Materiais e Métodos: Foram estudadas 29 estirpes de Campylobacter spp. isoladas em: carcaças, carne fresca e preparados de carne para serem consumidos cozinhados, provenientes de aves, suínos e bovinos. A espécie foi determinada por PCR em Tempo-Real com sondas de hibridação, a diversidade genótipica, por Multilocus sequence typing, e a resistência aos antimicrobianos, por difusão em disco. Resultados: Foram identificadas 24 estirpes da espécie Campylobacter coli (C. coli) e 5 da espécie C. jejuni. A genotipagem permitiu verificar que as estirpes de C. coli são geneticamente mais conservadas, identificando-se um complexo clonal predominante (CC-828), contrariamente ao observado para as estirpes de C. jejuni, todas de complexos clonais distintos. Foi observada uma elevada taxa de resistência aos antimicrobianos: 93.1% à ciprofloxacina, 82.8% à tetraciclina e 34.5% à eritromicina; sendo que 31% das estirpes apresentaram resistência aos três antibióticos testados. Conclusões: No âmbito deste estudo sublinhamos a presença de Campylobacter spp. multirresistente a antimicrobianos utilizados na terapêutica humana, em géneros alimentícios de origem animal. Reforçamos assim, a necessidade de implementar uma vigilância epidemiológica integrada da campilobacteriose em Portugal, envolvendo as vertentes humana, veterinária e alimentar.
- Campylobacter spp. in Portuguese fresh meat: use of filter membranes for the detection in food and resistance profile of the isolatePublication . Furtado, Rosália; Belo Correia, Cristina; Varela Flores, Cristina; Saraiva, Margarida; Santos, Andrea; Rodrigues, João Carlos; Oleastro, Mónica; Calhau, Maria AntóniaCampylobacteriosis is considered the main cause of acute gastroenteritis in the European Union with a continuous increase in reported cases over the last five years. Due to the global increase of antibiotics use in food animals production, antibiotic resistance has became a significant threat and a public health problem. As a consequence the number of humans cases infected by multiresistant strains of Campylobacter is growing. The aim of this study was to evaluate an alternative plating media for isolation of Campylobacter spp and determine the antibiotic resistance of the isolates. According to ISO 10272-1:2006 protocol plating, two different agars are specified, being the use of a mCCDA-based medium mandatory. Therefore, two plating techniques were used in parallel: plating in mCCDA medium and the filtration technique on the surface of Columbia Blood agar. In addition, a Karmali agar or a chromogenic agar was also used. During 2012/2013, a total of 184 samples of fresh meat were analyzed and a total of 37 isolates were recovered: 30 C. coli, 7 C. jejuni. The filtration technique provided the highest number of positive results for Campylobacter spp and reduced the interference caused by the background flora, preventing the occurrence of false negative results. It showed to be a simple technique, with an improved rate of isolation and recover of this pathogen, and reduced labor and costs. All isolates were tested for ciprofloxacin, tetracycline and erythromycin resistance, using the disc diffusion method. A high rate of resistance to these antibiotics was found. We also highlight the presence of multiresistant Campylobacter in food of animal origin to antibiotics used in human therapeutic. These results increase the importance of strengthening an integrated epidemiological surveillance of campylobacteriosis, involving the areas of animal health, food production and human health.
- Cephalosporin-resistant Neisseria gonorrhoeae isolated in Portugal, 2019Publication . Pinto, Miguel; Matias, Rui; Rodrigues, João Carlos; Duarte, Sílvia; Vieira, Luís; Gonçalves, Inês; Gonçalves, Maria João; Ramos, Maria Helena; Gomes, João Paulo; Borrego, Maria JoséWe report a multidrug resistant Neisseria gonorrhoeae exhibiting resistance to ceftriaxone and cefixime, isolated in Portugal in 2019. Whole-genome sequencing was performed for typing and identification of genetic determinants of antimicrobial resistance. Due to its antimicrobial susceptibility profile, awareness should be raised for the circulation of this strain.
- Epidemiological Data and Antimicrobial Resistance of Campylobacter spp. in Portugal from 13 Years of SurveillancePublication . Duarte, Andreia; Pereira, Luísa; Lemos, Maria-Leonor; Pinto, Miguel; Rodrigues, João Carlos; Matias, Rui; Santos, Andrea; PTCampyNet; Oleastro, MónicaThis study extensively analyzed campylobacteriosis surveillance in Portugal from 2009 to 2021, aiming to investigate demographic shifts, seasonal variations, and antimicrobial resistance (AMR) within Campylobacter isolates. Surveillance network and sentinel laboratory-based system data revealed a substantial under-notification of campylobacteriosis cases, suggesting an underestimated disease burden. Notification rates exhibited a paradigm shift, with a notable prevalence among the pediatric population, particularly in children aged 1-4 years, diverging from European reports. Additionally, an emerging trend of Campylobacter infections in younger adults (15-44 years) was observed. The study unveiled a unique seasonal distribution of cases, defying typical summer peaks seen elsewhere. AMR analysis revealed high resistance to ciprofloxacin and tetracycline, in both C. jejuni (93.7% and 79.2%, respectively) and C. coli (96.5% and 93.2%, respectively), stable throughout the studied period (2013-2021). C. coli exhibited significantly higher resistance to erythromycin, gentamicin, ampicillin and ertapenem compared to C. jejuni (p < 0.001). Multilocus Sequence Typing (MLST) data demonstrated the distribution of resistance markers across diverse sequence types, challenging the notion of a clonal origin for multidrug-resistant isolates. In conclusion, the study highlights the need for enhanced surveillance and raises concerns about alarming AMR levels, recommending the implementation of whole-genome sequencing (WGS)-based surveillance for a deeper comprehension of disease patterns and an evolving AMR landscape.
- Espécies exóticas em lagos ornamentais: adorno ou fonte de desequilíbrio?Publication . Nascimento, Maria; Paulino, Sérgio; Faria, Sónia; Cano, Manuela; Rosa, Nuno; Rodrigues, João Carlos; Reis, Lúcia; Jordão, LuísaEste trabalho teve como objetivo analisar a evolução sazonal da população de microrganismos dum lago ornamental da região de Lisboa.
- Fifteen years of a nationwide culture collection of Neisseria gonorrhoeae antimicrobial resistance in PortugalPublication . Pinto, Miguel; Rodrigues, João Carlos; Matias, Rui; Água-Doce, Ivone; Cordeiro, Dora; Correia, Cristina; Gomes, João Paulo; Borrego, Maria José; PTGonoNetNeisseria gonorrhoeae antimicrobial resistance (AMR) and gonorrhea disease burden remain major public health concerns worldwide. To contribute to the supranational demands to monitor and manage the spread of antimicrobial-resistant N. gonorrhoeae, the Portuguese NIH promoted the creation of the National Laboratory Network for Neisseria gonorrhoeae Collection (PTGonoNet). The present study reports the N. gonorrhoeae major AMR trends observed from 2003 up to 2018. All isolates described in the present study constitute the opportunistic ongoing N. gonorrhoeae isolate collection supported by the National Reference Laboratory for Sexually Transmitted Infections of the Portuguese NIH, enrolling strains isolated in 35 different public and private laboratories. Minimum inhibitory concentrations were determined using E-tests for azithromycin, benzylpenicillin, cefixime, ceftriaxone, ciprofloxacin, gentamicin, spectinomycin and tetracycline. Molecular typing was determined using NG-MAST. AMR data of 2596 country-spread isolates show that 87.67% of all N. gonorrhoeae isolates presented decreased susceptibility to at least one antimicrobial. A continuous decreased susceptibility and resistance to penicillin, tetracycline and ciprofloxacin can be observed along the years. However, no decreased susceptibility to cephalosporins was observed until 2018, while for azithromycin, this was always low. The most common observed NG-MAST genogroups were G1407, G7445, G225, G2, and G1034. This study evidences the advantages of a nationwide collection of isolates and of centralized AMR testing to respond to supranational (EURO-GASP) requirements while providing unprecedented data on AMR in the context of 15 years of surveillance.
- Infeção associada à prestação de cuidados de saúde por estirpe hipervirulenta de Clostridium difficile – descrição de um surtoPublication . Santos, Andrea; Rodrigues, João Carlos; Miron, Ludmilan; Carvalho, Isabel; Machado, Jorge; Oleastro, Mónica