
Carla ViegasInstituto Politécnico de Lisboa | ISEL
Carla Viegas
MsC, PhD
About
300
Publications
56,014
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,920
Citations
Citations since 2017
Introduction
The major field of study is occupational and environmental mycology leading and participating in several projects about both areas of expertise. Special interest are occupational exposure to fungi in highly contaminated settings and complementarity of conventional methods and molecular tools to assess fungi occupational exposure, and also fungal contamination in food commodities.
Additional affiliations
January 2012 - present
Universidade Técnica de Lisboa
January 2012 - present
September 2003 - present
Education
July 2007 - October 2010
Publications
Publications (300)
Microbial contamination in grocery shops (GS) should be evaluated since food commodities are commonly handled by workers and customers increasing the risk of food contamination and disease transmission. The aim of this study was to evaluate the microbial contamination in Portuguese and Spanish GS with a multi-approach protocol using passive (electr...
Background: Aspergillus fumigatus is a saprophytic fungus, ubiquitous in the environment and responsible for causing infections, some of them severe invasive infections. The high morbidity and mortality, together with the increasing burden of triazole-resistant isolates and the emergence of new risk groups, namely COVID-19 patients, have raised a c...
In poultry farms, the mixture of bedding material, chicken excrement, and feathers seems to play an important role in pathogen development which may contribute to a potential risk of zoonosis, spreading the disease through the food chain. The purpose of this study was to analyze microbial contamination in bedding material and other matrices as well...
Despite tea beneficial health effects, there is a substantial risk of tea contamination by harmful pathogens and mycotoxins. A total of 40 tea samples (17 green (raw) tea; 13 black (fermented) tea; 10 herbal infusions or white tea) were purchased from different markets located in Lisbon district during 2020. All products were directly available to...
Respiratory abnormalities among workers at coffee roasting and packaging facilities have already been reported; however, little is known about microbiological contamination inside coffee production facilities. This study intends to assess the microbial contamination (fungi and bacteria) in two coffee industries from Brazil with a multi-approach pro...
Objective This study aims to characterise the occupational exposure to the bioburden of groceries workers and to identify the most critical workstations. Background To our knowledge, this is the first study performed in Portugal that intends to characterise the microbial contamination in this specific setting. Method This study was conducted betwee...
Assuring a proper environment for the fulfillment of professional activities is one of the Sustainable Development Goals and is contemplated in the One Health approach assumed by the World Health Organization. This particular study is applied to an often neglected sector of our society—the conservators/restorers—despite the many health issues repor...
The sampling approach is of utmost importance to obtain data regarding microbial viability and truly assess workers’ potential health effects. The purpose of this assessment is to create a score which will provide up-to-date information to identify the most suitable sampling method to assess occupational exposure to fungi. Data from a sampling camp...
Previous studies anticipated that microorganisms and their metabolites in waste will increase as a consequence of a decreased collection frequency and due to differences in what kind of waste is bagged before collection leading to an increased exposure of workers handling the waste. This study aim was to investigate the microbial contamination pres...
Cemeteries are potential environmental reservoirs of pathogenic microorganisms from organic matter decomposition. This study aimed to characterize the microbial contamination in three cemeteries, and more specifically in grave diggers' facilities. One active sampling method (im-pingement method) and several passive sampling methods (swabs, settled...
Waste workers are exposed to bioaerosols when handling, lifting and dumping garbage. Bioaerosol exposure has been linked to health problems such as asthma, airway irritant symptoms, infectious, gastrointestinal and skin diseases, and cancer. Our objective was to characterize the exposure of urban collectors and drivers to inhalable bioaerosols and...
Staphylococcus aureus and particularly methicillin-resistant S. aureus (MRSA) infections are currently associated with extremely high morbidity and mortality rates worldwide. The global escalation in the development of antibiotic-resistant human pathogens and S. aureus ability in developing new clones with the capacity to invade community settings,...
Special Issue - "Indoor Air in Healthcare Facilities". https://www.mdpi.com/journal/applsci/special_issues/Healthcare_Indoor_Air
Deadline for manuscript submissions: 20 May 2022.
Electrostatic dust cloths (EDC) have been widely used for microbiologic contamination assessment in different indoor and occupational environments. This paper reviews sixteen studies performed in Portugal between 2018 and 2021 for evaluating the exposure to microbiological agents and focusing on fungi using EDC as a passive sampling method. The fin...
Healthcare units consist of numerous people circulating daily, such as workers, patients, and companions, and these people are vehicles for the transmission of microorganisms, such as bacteria. Bacteria species may have different allergenic, pathogenic, infectious, or toxic properties that can affect humans. Hospital settings foment the proliferati...
The composition of airborne microflora in sawmills may vary to a great degree depending on the kind of timber being processed and the technology of production being used. Cases of allergy alveolitis and asthma have been reported in woodworkers who were exposed to wood dust largely infected with microorganisms. The aim of this review article is to i...
In some occupational environments risk characterization is challenging or impossible to achieve due to the presence of multiple pollutants and contaminants. Thus, in vitro testing using the most relevant cell lines will provide information concerning health effects due to the co-exposure to multiple stressors. The aim of this review article is to i...
One of the occupational environments that need intervention to overcome the lack of information concerning exposure to biological agents is the Firefighter Headquarters’ (FFH). This study intends to assess the microbial contamination in Portuguese FFH with a multi-approach protocol for sampling and analyses using active (air samples by impaction an...
Safe working conditions must be guaranteed during waste sorting, which is crucial to maximizing recycling and reuse, in order to minimize workers’ exposure to chemical and biological hazards. This study determines the contribution of Aspergillus section Fumigati to the overall cytotoxicity of filtering respiratory protection devices (FRPD) and mech...
Objective: The aim of this study is to characterize the occupational exposure to bioburden of ambulance workers and to suggest control procedures to prevent microbial contamination. Background: Ambulances are of critical importance for health services. Thus effective cleaning protocols are essential. Method: This study was held during winter months...
The aim of this chapter is to present the challenges regarding occupational fungal burden assessment and the solutions to overcome them to allow exposure assessors/occupational hygienists to decide about sampling methods and assays aiming a reliable fungal risk characterization. Fungi occupational exposure can be estimated using a diversity of diff...
In healthcare environments, the presence of fungi depends on the medical activities performed, number and types of patients, cleaning frequency and procedures, and the type of ventilation systems. The aim of this review was to identify different methodologies applied to assess fungal contamination in healthcare environments, as well as to describe...
The International Panel on Climate Change (IPCC, 2013) and almost the entire scientific community agreed to consider the Mediterranean Area as one of the most vulnerable regions in the world to the impacts of global warming. In this scenario, heat waves, defined by the World Meteorological Organization as five or more consecutive days of heat reach...
This study analyzed 57 Aspergillus section Fumigati (AF) isolates collected by active and passive sampling (N = 450) in several health care facilities and from biological sampling of health care workers (N = 25) and controls (N = 22) in Portugal. All isolates were cultured in different media and screened for azole resistance. Cytotoxicity was asses...
Background:
Aspergillus section Fumigati is one of the Aspergillus sections more frequently related to respiratory symptoms and by other health outcomes. This study aimed to characterize Aspergillus section Fumigati distribution in eleven firefighter headquarters (FFHs) to obtain an accurate occupational exposure assessment.
Methods:
A sampling...
The higher education sector represents a unique environment and it acts as a work environment, a learning environment for students, and frequently, also a home environment. The aim of this study was to determine the microbial contamination (SARS-CoV-2, fungi, and bacteria) in Higher Education Facilities (HEI) by using active and passive sampling me...
Ambulance vehicles are an essential part of emergency clinical services. Bioburden control in ambulances, through cleaning and disinfection, is crucial to minimize hospital-acquired infections, cross contamination and exposure of patients and ambulances' crew. In Portugal, firefighter crews are responsible, besides fire extinction, for first aid an...
Filtering respiratory protection devices (FRPD) are mandatory for workers to wear in the Portuguese waste-sorting industry. Previous results regarding microbial contamination found on FRPD interior layer raised the question of whether microbial contamination from the exhalation valve would also have cytotoxicity effects. Since the FRPD exhalation v...
This study aims to assess the airborne bioburden of rural and urban Portuguese Primary Health Care Centers (PHCC) using active and passive sampling methods and identify the potential differences in airborne microbiota between both environments. The highest total aerobic mesophilic bacterial load in indoor air were found in the Vaccination Room (448...
Since the 1940s, humans have developed new drugs and consumption has increased significantly in the last 15 years. [...]
Sampling campaigns indoors have shown that occupants exposed to contaminated air generally exhibit diverse health outcomes. This study intends to assess the deposition rates of total settleable dust and bioburden in the indoor air of dwellings onto quartz fiber filters and electrostatic dust collectors (EDCs), respectively. EDC extracts were inocul...
Tea has been consumed for thousands of years. Despite the different varieties, particular emphasis has been placed on green tea (GT), considering the associated health benefits following its regular consumption, some of which are due to its polyphenol constituents, such as epigallocate-chin-3-gallate (EGCG). Tea is not prone to the growth of microo...
The SARS-CoV-2 exposure assessment is critical to implement control measures and guarantee safety of patients and workers from different occupational environments. The aim of this review article was to identify methodologies applied for SARS-CoV-2 sampling and analyses in environmental samples in different occupational and indoor environments. This...
Aspergillus section Fumigati is one of the sections of the Aspergillus genus most often associated with respiratory symptoms. The azole-resistant clinical isolates in this section have been widely described worldwide. More recently, the environmental origin of azole resistance has been correlated with the development of fungal diseases and therapeu...
Identification of Aspergillus to species level is important since sibling species may display variable susceptibilities to multiple antifungal drugs and also because correct identification
contributes to improve the knowledge of epidemiological studies. Two retrospective laboratory
studies were conducted on Aspergillus surveillance at the Portugues...
A wider characterization of indoor air quality during sleep is still lacking in the literature. This study intends to assess bioburden before and after sleeping periods in Portuguese dwellings through active methods (air sampling) coupled with passive methods, such as electrostatic dust cloths (EDC); and investigate associations between before and...
Aspergillus fumigatus (Aspergillus section Fumigati) is a thermophilic species of the Aspergillus genus and it is also a natural recycler with a versatile metabolism. This species is one of the main responsible for invasive aspergillosis and other health hazards. This study was based on a systematic search for information and data that have been pu...
Introduction:
The frequency in detection of azole-resistant Aspergillus fumigatus isolates has increased since 2010. In Portugal, the section Fumigati is one of the most frequent, and resistant strains to have been found in clinical and environmental contexts. Although several cryptic species within the Fumigati section show intrinsic resistance t...
Culturing is still the most widely used method for determining fungal growth. Thus, is important to identify the most suitable culture media to assess Aspergillus spp. The aim of this study was to analyze data obtained from previous studies, aiming at identifying the most suitable culture media (malt extract agar (MEA) or dichloran-glycerol agar (D...
One of the solutions for decreasing the workers' exposure to bioburden is the use of Filtering Respiratory Protective Devices (FRPD). As such it is important to determine whether these devices are fulfilling their protective role. This is the basis of the current study, aimed at characterizing bioburden retained by 120 FRPD (both in interior layers...
The organic material present on waste sorting units serve as a substrate for different microorganisms , increasing workers' exposure to Aspergillus spp. This study intends to assess the Aspergillus spp. contamination on Mechanical Protection Gloves (MPG) from different workstations and understand the role of MPG in workers' exposure to these genera...
Monitoring campaigns in several buildings have shown that occupants exposed to contaminated indoor air generally exhibit diverse health symptoms. This study intends to assess settleable dust loading rates and bioburden in Portuguese dwellings by passive sampling onto quartz fiber filters and electrostatic dust cloths (EDCs), respectively. Settled d...
The exposure to particles and bioaerosols has been associated with the increase in health effects in children. The objective of this study was to assess the indoor exposure to bioburden in the indoor microenvironments more frequented by children. Air particulate matter (PM) and settled dust were sampled in 33 dwellings and four schools with a mediu...
Association between selection pressure caused by the use of azole fungicides in sawmills and the development of fungal resistance has been described. The aim of this study was to implement an algorithm to assess the presence of Aspergillus section Fumigati resistant strains in sawmills.
Eighty-six full-shift inhalable dust samples were collected fr...
In occupational settings where exposure to organic dust occurs (e.g., intensive animal production, waste management, farming and many others) workers can also be exposed to mycotoxins. However, recognizing exposure to mycotoxins in workplace environments does not happen commonly and, consequently, remains as a not identified occupational risk facto...
The use of Filtering Respiratory Protective Devices (FRPD) is mandatory in Portugal to protect workers from the waste industry of harmful exposures. Deleterious health effects of exposure to bioburden via inhalation and/or ingestion include respiratory symptoms and nephrotoxicity. Between January and February 2019, 118 FRPD samples were collected i...
In Portugal, mechanical protection gloves (MPG) are of mandatory use and during their use sweat is released and, consequently, the humidity of the material increases leading to conditions favorable to the growth of microorganisms. However, no studies have been conducted in MPG to assess the bioburden. This study intended to determine the bioburden...
In recent times green tea (GT) consumption has increased, due to the numerous studies that indicate a wide variety of health benefits following its regular consumption. The aim of this study was to assess the bioburden (bacteria and fungi) of bulk and bags of GT marketed in Lisbon and to obtain a more refined fungal burden characterization, includi...
The assessment and control of microbial contamination in health care facilities is presently a mandatory and vital part of strategies to prevent and control hospital-acquired infections. This study aims to assess the bioburden with two passive sampling methods (30 ventilations grids swabs and 16 electrostatic dust collectors (EDCs)) at Clinical Pat...
This study aimed to provide a comprehensive characterisation of the indoor air quality during the sleeping period of 10 couples at Lisbon dwellings, using a multi-pollutant approach, and to understand how the compliance with legislation and guidelines was to assure a good indoor air quality. The assessment of indoor air quality was conducted in the...
Workers in the waste sorting industry are exposed to diverse bioaerosols. Characterization of these bioaerosols is necessary to more accurately assess the health risks of exposure. The use of high-throughput DNA sequencing for improved analysis of microbial composition of bioaerosols, in combination with their in vitro study in relevant cell cultur...
There is scientific evidence that associates occupational exposure to fungi in the waste industry to health outcomes, being Aspergillus genera reported as the most prevalent. During Filtering Respiratory Protective Devices (FFR) use, humidity and temperature conditions provide favorable conditions for Aspergillus growth. The aim of this study was t...
Joint Control Charts applied to Enironmental Health Data
For decades, occupational exposure to flour dust has been linked to a range of respiratory diseases, including occupational asthma, thought to result from exposure to fungi present in the flour. Antifungal resistance is of increasing prevalence in clinical settings, and the role of occupational and environmental exposures, particularly for specific...
Studies already reported that swimming pool facilities have contributed to the dissemination of fungal infections. Although most of the studies performed focused on dermatophytes and health effects (tinea pedis and onychomycosis), other clinically relevant fungi such as Fusarium spp., Aspergillus spp., and Candida spp., were reported on swimming po...
Air quality in school buildings is of the upmost importance, due to the susceptibility of its users (mostly children) to several illnesses, such as asthma and allergies, creating a need for a protocol to assess air quality, and more specifically to assess fungal contamination. This study aims to perform a scope review from 2000 to 2018 regarding th...
Fungi can be easily found in agriculture environments due to the good growth conditions that are provided by the raw materials present in this environment and for its storage temperatures. Due to the daily activities organic dust is present in these occupational environments, creating the optimal conditions for occupational exposure by inhalation r...
Microbiological exposures associated with waste can occur indoors, where waste is stored, or outdoors during its collection and it may be influenced by the process of sorting, transfer or cleaning. It has been shown that waste management releases airborne microorganisms and bioaerosols into the atmosphere around waste facilities and that temperatur...
Fungi are responsible for skin diseases, infections of lung and other organs and bloodstream infections due to its presence in several environments such as in agriculture. Antimicrobial resistance has been described as product of healthcare and agricultural overuse of azoles to inhibit fungal growth. The aim of this review article is to assess meth...
It is well known that fungi in indoor farm environments emerge and sporulate easily in low quality bedding or polluted feedstuffs. Among fungi the genera Aspergillus, Penicillium, Cladosporium, Alternaria, Rhizopus, Scopulariopsis and Trichophyton are commonly found inside breeding buildings. These pollutants can present a serious health hazard for...
One of the solutions for decreasing the workers' exposure to bioburden is the use of Filtering Respiratory Protective Devices (FRPD). As such it is important to determine whether these devices are fulfilling their protective role. This is the basis of the current study, aimed at characterizing bioburden retained by 120 FRPD (both in interior layers...
The bioburden in a Hospital building originates not only from patients, visitors and staff, but is also disseminated by several indoor hospital characteristics and outdoor environmental sources. This study intends to assess the exposure to bioburden in one central Hospital with a multi-approach protocol using active and passive sampling methods. Th...
Background:
Dairy farming feed can be contaminated with mycotoxins, affecting animals' health and milk quality. Dairy farming is also prone to occupational exposure to mycotoxins, and feed is recognized as a source of contamination in the workplace. An exploratory study was developed in a dairy farm located in Portugal intending to assess the myco...
Exposure to Aspergillus conidia is an increased risk factor for the development of respiratory symptoms. The emergence of azole resistance in Aspergillus fumigatus is a major concern for the scientific community. The aim of this study was to perform the molecular identification of Aspergillus species collected from different occupational and non-oc...
Several studies reported adverse respiratory health effects in workers exposed to ambient contaminants in bakeries. The aim of this study was to examine worker exposure to fungi and mycotoxins in Portuguese bakeries in order to develop new policies in occupational health. Environmental samples such as air, surfaces, settled dust and electrostatic d...
Exposure to bioburden (comprising bacteria and fungi) has become one of the critical issues for occupational and public health approaches in hospital environment. This study aims to assess the fungal burden in one Central Hospital in Oporto, Portugal, applying the Indoor Air Quality (IAQ) Portuguese legislation as guidance, verifying both the limit...
Mycotoxins are fungi metabolites produced by specific fungal genera and although the reported evidence about the health effects there is still a gap about data in health care enviroments. This study aimed to investigate if mycotoxins presence should be monitored in health care facilities by searching studies that reported fungal contamination by to...
The exposure to fungal burden is an increased risk factor for the development of respiratory symptoms and fungal diseases. The emergence worldwide of azole resistance in fungal species is a major concern for public health. Clinical settings must provide a clean and safe environment to protect patients and staff from fungal diseases. The aim of this...