DSA - Apresentações orais em encontros internacionais
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- Beach sand as a source of faecal indicator organismsPublication . Brandão, JoãoMicrobial life in beach sands research began in Bacteriology with Roger Fujioka of the University of Hawai'i and in Mycology with Laura Rosado, of the Portuguese National Institute of Health. Since then, many reports and scientific papers have been published on the subject. The number of publications in this area is currently increasing exponentially, most of which addressing methodological approaches and weaving considerations on the microbiome characterization and influence on human health. Levels of bacteriological indicators of bathing water quality are of concern due to run-offs and tide retractions. Clear and precise guidance on the subject, however, has been lost in time. It should serve as a working basis for regulators and research. Global warming and climate change also bring a regional de-characterization of the microbiota, due to the geographic expansion of endemic microbes. These bring along unexpected illnesses diagnosed with some degree of unexpectedness or difficulty by local clinicians. The following three points are currently of high relevance in sand contaminants: A. Sampling, representativeness and analytical methods: sand is patchy, not a homogeneous or a fluid system. In 2015, an open letter was published, as a result of a meeting of experts, from several scientific areas converging in one posture towards the issue of sand contaminants. During this meeting, it was decided that sampling should be evaluated, and that levels of relevance and clinical expression or influence of the quality of adjacent waters should stratify analytical methods. A basic analytical snapshot of the level of contamination of sand (sanitation), is inexpensive and its feasibility leads to easy transfer between laboratories. This allows it to become current practice and to integrate the process of quality regulation and public health protection. However, in pathogen detection situations, epidemiological outbreaks or over-dominance of unexpected and persistent microbial agents, the health risk or socio-economic implications should be assessed, and the causes identified, in order to be controlled or eradicated. There is present need to define levels of analysis in order to adopt the recommendation of the open letter, excluding neither classic nor molecular methodologies (namely, next generation sequencing, which allows the characterization of full microbiomes). B. Biological groups indigenous to beach sand, the definition or relevance of indicators and pathogens, and their forms of detection and counting, are being published without any methodological equivalence or biological relevance. The lack of regulation and international standards for the evaluation of contaminants in sand is generating a logistical nightmare for those who want to make interregional comparisons. A quantitative microbial risk assessment based on the clinical and safety aspects of several agents and biological groups is in order to pre-structure international regulation. Fecal indicator and other pathogenic or opportunistic bacteria from intertidal sands, as well as dry sand contamination resulting from animal shedding or direct sand / soil life, will be included in these groups; Enteric and respiratory viruses propagated through the environment (intertidal sands); Pathogenic, opportunistic and allergenic fungi; Parasites; and forms of allochthonous life as a consequence of sand nourishment. Considerations on environmental resistome of sand should not be excluded. C. Implications of climate change in sand / soil microbiome Extreme weather events, global warming and migration of endemic species are current factors that will dictate future risk assessments.
- Biofilms within the human body and its clinical implicationsPublication . Jordão, Luísa; Subtil, João; Lavado, Paula; Rodrigues, João; Reis, Lúcia; Faria, Isabel; Pessanha, Maria AnaBiofilms with medical implications could be find on medical devices or on organs. Here we discuss the results obtained in two studies one associated with an organ (adenoid) and another associated with a medical device (central venous catheters- CVC). In the first study, we evaluate the association between biofilm assembly on adenoids and the incidence of recurrent infections in a paediatric population comparing adenoid samples from adenoidectomy groups with and without infectious indication. Biofilms were present in 27.4% of the adenoid samples. For H. influenzae, S. aureus, S. pyogenes, S. pneumococcus and M. catarrhalis, no association was found between ability to assemble biofilms in vitro and the presence of biofilms on adenoids, and the same was found for antibiotic resistance. The most isolated bacterium was H. influenzae that revealed after further characterization to be non-typeable (NT). No statistical difference was found on biofilm presence between the two groups, infectious versus non-infectious diagnosis. The same was true for biofilm assembling ability of bacteria found on adenoid surface and core. As in other studies, we did not find a correlation between biofilm formation and susceptibility or resistance to antibiotics and this raise the question of the importance of biofilms on the pathogenesis of infectious diseases. In the second study, we explore the relation between the presence of biofilms on central venous catheters and central venous catheter-related bloodstream infection (CRBSI). Our preliminary results (relative to data collected over 10 months) show that Staphylococci, either coagulase negative or positive, are major etiologic agents of this healthcare associated infection.
- Effects of a Changing Earth on Microbial Dynamics and Human Health Risks in the Water/Sand ContinuumPublication . Weiskerger, Chelsea; Brandão, João; Robinson, Clare; Staley, Chris M.; Kleinheinz, Greg; Nshimyimana, Jean Pierre; Kinzelman, Julie; Nevers, Meredith B; Sadowsky, Michael Jay; Phanikumar, Mantha S; Whitman, Richard; Edge, Tom Andrew; Piggot, Alan; Boehm, Alexandria; Aslan, Asli; Badgley, Brian; Heaney, Christopher; Symonds, Erin; Solo-Gabriele, Helena; Fleisher, Jay; Harwood, Jody; Yamahara, Kevan; Vogel, Laura; Jordão, Luisa; Avolio, Lindsay; Merilainen, Paivi; Pitkanen, Tarja; Warish, Ahmed; Staley, Zachery; Klaus, JamesHumans may be exposed to microbial pathogens at recreational beaches via environmental sources such as water and sand. Although infectious disease risk from exposure to waterborne pathogens, and the fecal indicator bacteria (FIB) used to monitor water quality are active areas of research, sand is a relatively unexplored reservoir of pathogens and FIB. Sand and water at beaches experience continuous exchange of microorganisms, and these habitats provide unique advantages and challenges to pathogen introduction, growth, and persistence. Models of FIB and pathogen fate and transport in beach habitats can aid prediction of the risk of infectious disease from recreational water use, but filling knowledge gaps is necessary for accurate modeling. Climate change predictions estimate an increase in global temperatures of 2.5 – 10° F, sea level rise, and intensification of storms and precipitation in some regions. Other global change factors like population growth and urbanization may exacerbate predicted impacts. These changes can alter microbial population dynamics in beach habitats, and may consequently affect the assumptions and relationships used in numerical models. We discuss literature on microbial population and transport dynamics in sand/beach habitats, with an emphasis on how climate change and other anthropogenic influences (e.g., land use, urbanization) should be considered when using and developing models.
- Exploring fungal contamination in the sand and water around the Mediterranean Sea and other water bodies of EuropePublication . Brandão, JoãoResearch on microbial life in beach sands began during the 1980s. Since then, many reports and scientific papers have been published on the subject. Especially after the year 2000, the number of publications in this area has been increasing exponentially. Many of these address methodological approaches and considerations on the microbiome characterisation and its influence on human health. Clear and precise guidance on the subject, however, has not been achieved. Global warming and climate change is expected to generate a regional de-characterization of the microbiota, due to the geographic expansion of endemic microbes. This will originate infections which are diagnosed with some degree of unexpectedness or difficulty by local clinicians. Much has happened pointing out variants of concerns implicated in future regulation of microbial sand contamination. Yet, most groups working in this theme have one aim and one aim only: To avoid run-off and tide retraction contamination of recreational waters by whatever may lie in the sand (specifically, fecal indicator bacteria, the current parameters used in recreational water quality regulation due to their strong correlation with waterborne gastro-intestinal illness). In light of this fact, a group of medical mycologists and some water microbiologists got together to voluntarily help generate data on fungal contaminants in beaches of Europe. The idea behind the project is to create recommendations of experts on fungal contaminants, who have the knowledge and capability to point out and demonstrate that certain groups of fungi also matter when in the sand, be it beach or of recreational sandboxes and parks. Some of the fungi can also clarify the type of microbial pollution on beach sand, regardless of its taxonomic nature
- Exploring the aquatic resistomePublication . Rosado, Tânia; Manageiro, Vera; Balata, Duarte; Menezes, Carina; Ferreira, Eugénia; Paulo, Octávio; Caniça, Manuela; Dias, ElsaAntibiotic resistance is one of the major problems in public health today since the failure of antibiotherapy has dramatic clinical implications such as the increase of mobility/mortality and of health costs. Antibiotic resistance is a dynamic process since antibiotic-resistant microorganisms, and the corresponding genetic material, flows and disseminates among several settings simultaneously: humans, animals and natural habitats. Water environments are recognized as important pools of antibiotic pollution and antibiotic resistance genes, but the water resistome (collection of all genes responsible for antibiotic resistance in water environments) is far from being characterized. It is well known that antibiotic pollution affects the structure/functioning/diversity of aquatic ecosystems, namely the cyanobacteria community. However, the role of cyanobacteria in the context of antibiotic resistance was never characterized. In this presentation, the aims, the team, the methodologies and the preliminary results of the national project EXPLORAR – Exploring the Aquatic Resistome (PTDC/BIA-BMA/31451/2017), founded by the Portuguese Foundation for Science and Technology (FCT, PT) will be discussed. In this project, we are investigating the contribution of indigenous freshwater organisms (cyanobacteria and bacteria) to water resistome. We expect to identify and characterize ecological niches associated with antibiotic resistance in freshwater environments. This may contribute to define a monitoring strategy to map the antibiotic resistance profiles of national freshwater resources. We expect to contribute to the definition of preventive measures against the dissemination of antibiotic resistance in the environment.
- Exposure to fungal particles in sand. Why only water quality is assessed for safety in recreational settings?Publication . Brandão, JoãoFungi were never introduced to water quality regulations, the incidence of fungal infections worldwide is growing, and changes in antimicrobial resistance patterns are taking place. The presence of fungi in different types of water has been thoroughly investigated during the past 30 years only in Europe, and more than 400 different species were reported from ground-, surface-, and tap-water. The most frequently reported fungi, however, were not waterborne, but are frequently related to soil, air, and food.
- Freshwater cyanobacteria and antibiotic pollution: The Ecotoxicological and Antibiotic Resistance perspectivesPublication . Dias, Elsa; Vasconcelos, Vitor; Caniça, ManuelaThe release of antibiotics in natural ecosystems led to the development of antibiotic resistant (AR) microorganisms and alters the diversity/functioning of natural microbial communities. Freshwater cyanobacteria (CB) have been considered sensitive to antibiotics and they have been used as biologic indicators in environmental risk assessment of water contaminants, such as antibiotics. However, we have shown that CB strains from water environments exhibits reduced susceptibility to some antibiotics (nalidixic acid, trimethoprim), irrespective of the tested specie (Microcystis aeruginosa, Aphanizomenon gracile; Anabaena berghii, Planktothrix agardhii, Planktothrix mougeotti). The failure to detect genes conferring resistance to these antibiotics by PCR does not exclude the possibility of CB harbor AR determinants. NGS sequencing will help us to understand if unknown AR genes are present in CB genomes. Besides, we may also hypothesize that CB are intrinsically resistant to those compounds. On the other hand, the susceptibility to other antibiotics depended of the specie and/or the specie origin (freshwater reservoirs, wastewater treatment plants). Moreover, we also detect genes associated with resistance to other antibiotics (streptomycin, sulfonamides) and a class-1-type integron, in some strains. This suggests that CB might acquire resistant determinants from AR microbiota sharing the same habitats. Thus, the impact of antibiotic pollution in natural occurring CB is far from being elucidated. CB seems to have a role on water resistome but CB communities and their important ecological roles (primary and O2 production, CO2 fixation) may be also hampered by antibiotic exposure.
- House dust fungal communities’ characterization: a double take on the six by sixty by six project (6x60x6)Publication . Amaro, R.; Coelho, S.D.; Pastorinho, M.R.; Taborda-Barata, L.; Vaz-Patto, M.A.; Monteiro, M.; Nepomuceno, M.; Lanzinha, J.C.G.; Teixeira, J.P.; Pereira, C.C.; Sousa, A.C.A.Fungi are a group microbes, that are found with particular incidence in the indoor environment. Their direct toxicity or capability of generating toxic compounds has been associated with a large number of adverse health effects, such as infectious diseases, allergies and other toxic effects. Our study aims to quantify and identify the fungal community on house dust samples collected using two different methodologies (an approach not often seen in the literature): active (vacuum cleaner bags) and passive sampling (dust settled in petri dishes).
- It’s not just the water: beach sand as a potentially overlooked source of human, environmental, and animal diseasePublication . Chelsea, Weiskerger; Brandão, JoãoThe connections between water, food, energy, and climate are becoming clearer as we increase our understanding of the world around us. Recreational health policy, however, is lagging behind the research. In certain situations, the impacts of this lag could substantially affect the health of beach users. In recent years, research has indicated that beach sand can be a substantial source of fecal indicator bacteria and may provide more of a risk for beachgoers than recreational water itself. Further, the prevalence of contaminants in beach sand can provide a “One Health” issue: in addition to people contacting contaminants in beach sand, wildlife and pets are also exposed to sand, potentially leading to animal diseases. Additionally, contaminants in sand may degrade the environmental health of beaches through the development of biofilms and complex microbial communities that include may pathogens and opportunists. All of these issues may be affected by climate, food, and energy development, and subsequently may cause economic problems associated with healthcare costs, enhanced beach management/cleanup, and tourism losses due to beach closures. Despite this knowledge of beach sand as a source of human, animal, economic, and environmental health concerns, only three nations have recognized sand as a potential source of beach contamination, and only one has taken steps to effectively manage sand contamination for beach health. As we move forward with research, directed by both the water, food, energy, and climate nexus and One Health frameworks, the health and safety of beachgoers will depend upon development of policies to address beach sand and water contamination.
- Microbial Sand Dynamics Influencing FIB Levels at Beaches and Potential Climate Change InfluencesPublication . Solo-Gabriele, Helena; Brandão, João; Whitman, RichardIntroductory presentation to a scientific discussion on the influence of climatic elements on microbial sand contaminants.