Microbiological assessment of indoor air quality at different hospital sites

Poor hospital indoor air quality (IAQ) may lead to hospital-acquired infections, sick hospital syndrome and various occupational hazards. Air-control measures are crucial for reducing dissemination of airborne biological particles in hospitals. The objective of this study was to perform a survey of bioaerosol quality in different sites in a Portuguese Hospital, namely the operating theater (OT), the emergency service (ES) and the surgical ward (SW). Aerobic mesophilic bacterial counts (BCs) and fungal load (FL) were assessed by impaction directly onto tryptic soy agar and malt extract agar supplemented with antibiotic chloramphenicol (0.05%) plates, respectively using a MAS-100 air sampler. The ES revealed the highest airborne microbial concentrations (BC range 240-736 CFU/m(3) CFU/m(3); FL range 27-933 CFU/m(3)), exceeding, at several sampling sites, conformity criteria defined in national legislation [6]. Bacterial concentrations in the SW (BC range 99-495 CFU/m(3)) and the OT (BC range 12-170 CFU/m(3)) were under recommended criteria. While fungal levels were below 1 CFU/m(3) in the OT, in the SW (range 1-32 CFU/m(3)), there existed a site with fungal indoor concentrations higher than those detected outdoors. Airborne Gram-positive cocci were the most frequent phenotype (88%) detected from the measured bacterial population in all indoor environments. Staphylococcus (51%) and Micrococcus (37%) were dominant among the bacterial genera identified in the present study. Concerning indoor fungal characterization, the prevalent genera were Penicillium (41%) and Aspergillus (24%). Regular monitoring is essential for assessing air control efficiency and for detecting irregular introduction of airborne particles via clothing of visitors and medical staff or carriage by personal and medical materials. Furthermore, microbiological survey data should be used to clearly define specific air quality guidelines for controlled environments in hospital settings.

Potential pathogenic fungi assessment through molecular biology in cork industry

Portugal has been the world leader in the cork sectr in terms of exports, employing ten thousands of workers. In this working activity, the permanent contact with cork may lead to the exposure to fungi raising concerns as occupational hazards in cork industry. A study was developed aiming at assessing fungal contamination due to Aspergillus fumigatus complex and Penicillium glabrum complex by molecular methods in three cork industries in the outskirt of Lisbon city. The chosen fungal species are the ones most frequently associated with respiratory problems in workers from these industries.

Exposição ocupacional a bioaerossóis durante atividades de limpeza de quartos de hotel

O presente estudo pretende avaliar a exposição ocupacional a contaminação fúngica e bacteriana em quartos de hotel, mais precisamente em dois quartos com características diferentes, nomeadamente, com pavimento em alcatifa e outro sem alcatifa. Doze amostras de ar de 250L foram colhidas pelo método de impacto, em meio agar de extracto de malte (MEA) suplementado com cloranfenicol (0,05%) para fungos e em meio de TSA (agar de soja tríptica) com nistatina (0,2%) para bactérias. Foram também realizadas amostras de superfície nos mesmos locais. Em ambos os quartos apenas uma amostra de ar, no quarto sem alcatifa, apresentou contagens de fungos mais elevadas do que no exterior. No entanto, as concentrações de bactérias no ar interior foram superiores às do ar exterior. Em relação às superfícies, o quarto sem alcatifa apresentou diferenças estatisticamente significativas em relação ao quarto com alcatifa, sendo que o primeiro apresentou concentrações mais elevadas de fungos. Todas as superfícies analisadas apresentaram contaminação bacteriana, mas não houve diferenças estatisticamente significativas entre os quartos. Os géneros de fungos mais prevalentes no ar foram idênticos em ambos os quartos (Penicillium sp. 40,7% - 12,3% e Cladosporium sp. 43,5% - 55,4%). Nas superfícies analisadas, os isolados pertencentes ao complexo Aspergillus fumigatus foram os únicos encontrados no quarto com alcatifa, enquanto no outro quarto os géneros mais prevalentes foram Penicillium sp. (63,6%) e Aspergillus sp. (13,6%).

Fungal contamination in one hotel room: does carpet coating in the floor enhance fungal contamination?

Interest in bioaerosol exposure has increased significantly because it is now recognized that exposure to fungal agents is associated with a wide range of adverse health effects with a major impact on public health. Fungi are able to grow on almost all natural and synthetic materials, especially if they are hygroscopic or wet. Aim of the study: Several materials used indoors can contribute to enhance fungal contamination indoors. This study intended to understand the carpet influence on fungal contamination when used in the floor of a hotel room.

Accessing occupational exposure to fungi in a cork industry

Different forms of fungal diseases affecting the nose and paranasal sinuses are recognized, including invasive and non-invasive fungal rhinosinusitis. Penicillium glabrum complex is associated with respiratory diseases such as suberosis, a typical disease of cork industry workers. In addition, Chrysonilia sitophila has been described as causing occupational asthma, associated to prolonged exposure to high counts of spores. In this study we aimed to access fungal exposure in workers from one cork industry through the mycological analysis of their nasal exudate and the environmental fungal contamination of their surroundings as well.

Exposure and risk assessment in occupational exposure to fungi: aspects to consider in highly contaminated settings

Although a clear correlation between levels of fungi in the air and health impacts has not been shown in epidemiological studies, fungi must be regarded as potential occupational health hazards. Fungi can have an impact on human health in four different ways: (1) they can infect humans, (2) they may act as allergens, (3) they can be toxigenic, or (4) they may cause inflammatory reactions. Fungi of concern in occupational hygiene are mostly non-pathogenic or facultative pathogenic (opportunistic) species, but are relevant as allergens and mycotoxins producers. It is known that the exclusive use of conventional methods for fungal quantification (fungal culture) may underestimate the results due to different reasons. The incubation temperature chosen will not be the most suitable for every fungal species, resulting in the inhibition of some species and the favouring of others. Differences in fungi growth rates may also result in data underestimation, since the fungal species with higher growth rates may inhibit others species’ growth. Finally, underestimated data can result from non-viable fungal particles that may have been collected or fungal species that do not grow in the culture media used, although these species may have clinical relevance in the context. Due to these constraints occupational exposure assessment, in setings with high fungal contamination levels, should follow these steps: Apply conventional methods to obtain fungal load information (air and surfaces) regarding the most critical scenario previously selected; Guideline comparation aplying or legal requirements or suggested limits by scientific and/or technical organizations. We should also compare our results with others from the same setting (if there is any); Select the most suitable indicators for each setting and apply conventional-culture methods and also molecular tools. These methodology will ensure a more real characterization of fungal burden in each setting and, consequently, permits to identify further measures regarding assessment of fungal metabolites, and also a more adequate workers health surveillance. The methodology applied to characterize fungal burden in several occupational environments, focused in Aspergillus spp. prevalence, will be present and discussed.

New approach to study the real exposure to fungi in cork industry: nasal swabs mycobiota investigation coupled with screening on fungal resistance to azoles

The permanent contact with cork may lead to constant exposure to fungi, raising awareness as a potential occupational hazard in the cork industry.The presence of fungi belonging to the Penicillium glabrum complex has been associated with the development of respiratory diseases such as suberosis, one of the most prevalent diseases among workers from cork industries, besides occupational asthma. Azoles are used as pesticides but also the first line therapy in the treatment of Aspergillus infections; azole-resistance as been described as to have also an environmental source and is considered an emerging public health problem.The aim of this work was to characterize fungal distribution and to evaluate the presence of azole-resistant Aspergillus isolates in nose swab samples from the cork industry workers.