Vânia Ferreira

Vânia Ferreira
Universidade Católica Portuguesa | UCP · Escola Superior de Biotecnologia

Ph.D. in Biotechnology with specialization in Microbiology

About

82
Publications
12,431
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1,960
Citations
Citations since 2017
34 Research Items
1334 Citations
2017201820192020202120222023050100150200250
2017201820192020202120222023050100150200250
2017201820192020202120222023050100150200250
2017201820192020202120222023050100150200250
Introduction
Vânia Ferreira is a researcher at Centro de Biotecnologia e Química Fina (CBQF), Escola Superior de Biotecnologia – Universidade Católica Portuguesa (ESB-UCP), since 2011. With a PhD in Biotechnology, with specialization in Microbiology, (completed in 2010) her main research area focuses on characterization of foodborne pathogens, using phenotypic and genotypic tools, to provide scientific knowledge and research data needed to develop effective measures of controlling microbial hazards in foods. She is also interested in assessing the effects of environmental stresses, as those impaired by food processing and food matrices, on the virulence potential of Listeria monocytogenes.

Publications

Publications (82)
Chapter
Listeria monocytogenes is a ubiquitous microorganism responsible for listeriosis, a severe disease in humans that become infected by ingesting contaminated foods. Although it can occur in healthy humans, listeriosis affects mainly the elderly, immuno-compromised, pregnant women and newborns, with a high case fatality rate (20%–30%). This article wi...
Article
Full-text available
Campylobacter is the leading bacterial cause of diarrheal disease worldwide and poultry remains the primary vehicle of its transmission to humans. Due to the rapid increase in antibiotic resistance among Campylobacter strains, the World Health Organization (WHO) added Campylobacter fluoroquinolone resistance to the WHO list of antibiotic-resistant...
Article
Full-text available
This study evaluates the potential of pasteurised eggs to be used as a replacement for raw eggs in recipes where eggs remain uncooked or undercooked. Sensory tests were performed by 178 untrained panellists (143 from Portugal and 35 from Romania) using a 9-point hedonic scale. The tested recipes were tiramisu, chocolate mousse, eggnog, hollandaise...
Article
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Water contaminated with microbiological and chemical constituents can cause a variety of diseases. Water bodies may become contaminated by wild and domestic animal feces, agricultural runoff or sewage, and are often overlooked as a reservoir and source of human infection by pathogenic microorganisms. The objectives of this study were to evaluate th...
Article
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Epidemiological studies show that improper food handling practices at home account for a significant portion of foodborne illness cases. Mishandling of raw meat during meal preparation is one of the most frequent hazardous behaviours reported in observational research studies that potentially contributes to illness occurrence, particularly through...
Article
In Europe, salmonellosis has been ranked as the second leading cause of hospitalization and death due to the consumption of contaminated food. Information about consumers’ food safety perception, knowledge and practices in the domestic environment is lacking in order to define the main intervention opportunities to obtain a significant reduction in...
Article
Full-text available
C ampylobacter spp. are the most common bacterial pathogens associated with human gastroenteritis in industrialized countries. Contaminated chicken is the food vehicle associated with the majority of reported cases of campylobacteriosis, either by the consumption of undercooked meat or via cross- contamination of ready-to-eat (RTE) foods during the...
Article
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Nontyphoidal salmonellae are among the most prevalent foodborne pathogens causing gastrointestinal infections worldwide. A high number of cases and outbreaks of salmonellosis are associated with the consumption of eggs and egg products, and several of these occur at the household level. The aim of the current study is to critically evaluate the cur...
Article
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About 40% of foodborne infections are acquired in the home. The aim of the present study was to track contamination of pathogens during domestic food preparation and link the contamination to preparation practices. Research participants from 87 households in six European countries were observed and interviewed during shopping and preparation of a c...
Article
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Sponges are frequently used in kitchens and have been shown to harbor large numbers of bacteria, occasionally also pathogens. Less is known about kitchen brushes regarding usage and presence of bacteria. In the present study, the use of sponges and brushes was studied in a survey among 9966 European consumers in ten countries, and growth and surviv...
Article
Full-text available
Contaminated poultry is the major vehicle for consumer's exposure to Campylobacter. This study aimed to perceive potential cross-contamination events during preparation of raw poultry that can contribute to the spread of Campylobacter spp. in domestic kitchen environments and to understand consumers' meanings and justifications on preparation of a...
Article
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In addition to environmental pollution issues, social concerns about the sustainability, safety, and quality of conventionally grown fruits and vegetables have been increasing. In order to evaluate if there were any microbiological differences between samples of organic and conventional lettuce, a wide range of parameters were tested, including pat...
Chapter
Conventional methods for the detection of Listeria monocytogenes in foods and environmental samples rely on selective pre-enrichment, enrichment, and plating. This is followed by confirmation of suspected colonies by testing a limited number of biochemical markers.
Article
Full-text available
The aim of this study was to conduct a preliminary investigation on the occurrence of Salmonella spp. in eggs from chickens raised in backyards in Portugal and Romania. A lack of compliance with safety practices by chicken owners, was demonstrated, especially in Portugal, as 96% of the eggs were visibly dirty and 92.5% were stored at room temperatu...
Article
Full-text available
Cleaning is a method at the disposal of domestic cooks for curtailing the dispersal of foodborne pathogens in the process of preparing food. The observation of visible dirt/soil ‘in the wrong place’ operates as one of the stimuli for action. This paper makes a transdisciplinary contribution to understandings of cleaning as a practice for ensuring s...
Article
Full-text available
A transdisciplinary observational study, coupled with a web-based survey, was conducted to investigate refrigerated storage of food, in five European countries. The investigated consumer groups in this study were: young families with small children and/or pregnant women, elderly people, persons with an immunodeficient system, and young single men....
Article
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The objective of this work was to investigate the effect of stress conditions frequently encountered in food- associated environments on virulence-associated characteristics of eight strains of Listeria monocytogenes. Strains were grown at low (11 °C, cold stress) and optimal (37 °C) temperatures and in high NaCl concentrations (6% NaCl, 11 °C; col...
Article
Non-thermal food processing and replacement of chemical additives by natural antimicrobials are promising trends in the food industry. The objective of the present work was to evaluate the effect of a process which combines mild high hydrostatic pressure - HHP (200 and 300 MPa, 5 min, 10 °C), phage Listex™ P100 and the bacteriocin pediocin PA-1 as...
Article
The application of lytic phages as biocontrol agents is emerging as a promising strategy towards elimination or reduction of foodborne pathogens in a variety of food products. This technology is particularly advantageous for minimally processed and ready-to-eat (RTE) foods. In this study, the potential use of Listex™ P100 combined with high hydrost...
Article
Full-text available
We report here the draft genome sequence of Listeria monocytogenes 2542, a serotype 4b clinical strain recovered from a placental sample during a cheese-related listeriosis outbreak in Portugal.
Article
Naturally fermented meat sausages have a long tradition in Mediterranean countries and are one of the most important groups of traditional foods consumed throughout Europe. Despite all the advances in food science and technology and increased regulatory requirements and concerns for safety and quality during the last decades, the challenge to contr...
Article
The potential of constructed wetlands (CWs) as a low technology for wastewater treatment is timely but there is a need to understand the route of pathogenic bacteria (Listeria monocytogenes and Salmonella spp.) and indicator organisms (Enterobacteriaceae and Escherichia coli) present in wastewater within those systems and to what extent they can co...
Article
Full-text available
Contaminated food with Listeria monocytogenes is the predominant route of transmission of listeriosis to humans, a severe illness with a high mortality rate. Food processing environments can be colonized by persistent strains, repeatedly isolated for months or years. This study aimed to investigate the biofilm formation capacity of six strains of L...
Article
Free access to this article valid for 50 days, until March 25, 2017: https://authors.elsevier.com/a/1UV3B2eGSbKA-q The effect of high hydrostatic pressure (HHP) on the survival of 14 strains of Listeria monocytogenes from food or clinical origins, selected to represent different pheno and genotypes, was evaluated. Stationary phase cells were submi...
Article
The ongoing rise of antibiotic resistant microbial pathogens has become one of the major public health threats worldwide. Despite all the effort and actions taken so far, a proliferation of antibiotic resistant (AR) and multi-antibiotic resistant (MAR) strains is still observed, including in foodborne pathogens. This trend has been also noted recen...
Article
Listeria monocytogenes is a food-borne pathogen responsible for outbreaks and sporadic cases of listeriosis, a severe invasive disease. Internalin A (InlA) a protein encoded by inlA has a key role in the mechanism of pathogenesis in L. monocytogenes infection, specifically in the invasion of human intestinal epithelial cells. Studies on inlA have s...
Article
Aims: The main goal was to estimate the prevalence of methicillin-resistant S. aureus on hands and in nose of healthcare professionals. Methods and results: Detection of S. aureus on hands or in the nose of 169 individuals was performed. Nasal and hand carriage was found in 39.6% and in 8.9%, respectively. 17.2% of the individuals were carriers...
Article
This study aimed to investigate the effect of different conditions, including temperature (37 ºC, 22 ºC, and 4 ºC), NaCl concentrations (2.5%, 4%, and 8%), and acidity (pH = 5), on the growth response of persistent and non-persistent isolates of Listeria monocytogenes. The resistance to two common sanitizers (benzalkonium chloride and hydrogen pero...
Chapter
A significant challenge for traditional food production is to improve its competitiveness by identifying innovations that guarantee the safety of the products, while at the same time meeting general consumer demands and specific consumer expectations towards traditional food (European Research on Traditional Food, EC, DG_Research, 2007). Therefore,...
Article
Relatively little is known about the role of foods in the chain of transmission of acinetobacters and the occurrence of different Acinetobacter spp. in foods. Currently, there is no standard procedure to recover acinetobacters from food in order to gain insight into the food-related ecology and epidemiology of acinetobacters. This study aimed to as...
Article
In Portugal, listeriosis has been notifiable since April 2014, but there is no active surveillance programme for the disease. A retrospective study involving 25 national hospitals led to the detection of an outbreak that occurred between March 2009 and February 2012. The amount of time between the start of the outbreak and its detection was 16 mont...
Article
Full-text available
Listeria monocytogenes is a ubiquitous microorganism responsible for listeriosis, a rare but severe disease in humans, who can become infected by ingesting contaminated food products, namely dairy, meat, fish, and vegetables. Although it can occur in healthy humans, listeriosis mainly affects the elderly, immunocompromised, persons pregnant women,...
Article
Full-text available
Abstract Listeria monocytogenes infection (listeriosis) is an uncommon but severe foodborne illness that affects mainly individuals with recognized underlying conditions: the elderly, immunocompromised individuals, and pregnant women and their fetuses. The aim of this study was to obtain epidemiological data on cases of listeriosis occurring in Por...
Article
Conventional methods for the detection of Listeria monocytogenes in foods and environmental samples relies on selective pre-enrichment, enrichment, and plating. This is followed by confirmation of suspected colonies by testing a limited number of biochemical markers.
Article
Full-text available
Over the last 10 to 15 years, increasing evidence suggests that persistence of Listeria monocytogenes in food processing plants for years or even decades is an important factor in the transmission of this foodborne pathogen and the root cause of a number of human listeriosis outbreaks. L. monocytogenes persistence in other food-associated environme...
Article
Listeria monocytogenes is a ubiquitous bacterium widely distributed in the environment that can cause a severe disease in humans when contaminated foods are ingested. Cheese has been implicated in sporadic cases and in outbreaks of listeriosis worldwide. Environmental contamination, in several occasions by persistent strains, has been considered an...
Article
Abstract The aim of this study was to characterize a broad collection of isolates of Listeria monocytogenes, of different serotypes, recovered in Portugal between 2003 and 2007 from foods (n=353) and from clinical cases of human listeriosis (n=95), in terms of antimicrobial susceptibility. All the isolates were susceptible to ampicillin, the prefer...
Article
Full-text available
Objective. A total of 725 Listeria monocytogenes isolates, 607 from various foods and 118 from clinical cases of listeriosis, were investigated concerning their ability to form biofilms, at 4°C during 5 days and at 37°C during 24 h. Methods. Biofilm production was carried out on polystyrene tissue culture plates. Five L. monocytogenes isolates were...
Article
The effects of previous exposure to sub-lethal acidic and osmotic stresses on the survival of Listeria monocytogenes during exposure to gastro-intestinal (GI) tract simulation, was investigated. Six L. monocytogenes strains isolated from cheeses were selected and exposed to high salt concentrations or acidic conditions and their viability compared...
Article
D values were calculated at 55, 60 and 65 °C for five Listeria monocytogenes isolates using alheira (traditional Portuguese sausage) food matrix as heating menstrum. z values were also calculated and combined with internal alheiras temperature profiles during cooking in multiple ways, allowed estimations of percentages of L. monocytogenes survival....
Article
Full-text available
The persistence of Listeria monocytogenes in food-associated environments represents a key factor in transmission of this pathogen. To identify persistent and transient strains associated with production of fermented meat sausages in northern Portugal, 1,723 L. monocytogenes isolates from raw material and finished products from 11 processors were i...
Conference Paper
Pathogenic microorganisms such as Listeria monocytogenes are known to form biofilms. The risk of contamination of food products in the food industry and growth on medical devices in the clinical environment is a cause of concern. The objectives of this work were to examine and compare biofilm formation by food and clinical isolates of L. monocytoge...
Article
Full-text available
The bacterial genus Listeria contains pathogenic and non-pathogenic species, including the pathogens L. monocytogenes and L. ivanovii, both of which carry homologous virulence gene clusters such as the prfA cluster and clusters of internalin genes. Initial evidence for multiple deletions of the prfA cluster during the evolution of Listeria indicate...
Data
Table in MS Excel with presence or absence of 78 virulence associated genes in the genomes of the genus Listeria.
Data
Full-text available
Primer sequences of primers used to confirm absence of specific virulence associated genes.
Data
Excel file containing presence/absence data of genes in the Listeria pan-genome.
Data
Full-text available
PDF file containing a graphic comparison of the prfA cluster region
Data
Full-text available
PDF-file with gene trees based on internalin genes.
Data
Excel file SNP differences between L. monocytogenes F2365 and its duplicate FSL R2-574 and results of Sanger sequencing SNP confirmation.
Data
Full-text available
PDF file containing a graphic comparison of the inlAB region.
Data
PDF file containing a graphic comparison of internalin GHE region. Gray arrows indicate conserved genes adjacent to the region.
Article
Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chouriça de Vinhais and Salpicão de Vinhais, fermented meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus...
Article
Salpicão de Vinhais and Chouriça de Vinhais are traditional dry-fermented meat sausages produced in the North of Portugal. The microbiological profile during production of both products was followed in three small processing units. Lactic acid bacteria were the most prevalent microorganisms, with enhanced growth during the smoking process and a con...
Article
"Chouriça de Vinhais" and "Salpicão de Vinhais" are traditional smoked naturally fermented meat products produced in the North of Portugal, Trás-os-Montes. The objective of this study was the characterisation of these products, giving particular attention to their microbiological and chemical safety. Nitrite, nitrate, heavy metals and biogenic amin...
Article
The objective of this study was the characterisation of alheiras, traditional Portuguese sausages, with respect to their microbiological safety. Thirty-eight lots from 17 producers were analysed. The microbiological status of the analysed product can be considered of concern in terms of food safety. Although Campylobacter spp. and Escherichia coli...
Article
Alheiras are traditional smoked naturally fermented meat sausages produced in the north of Portugal. They have not previously been characterized as to their chemical and microbiological status. pH and salt levels are insufficient to assure microbiological safety, there is ample opportunity for post-cooking contamination; the products require chill...
Presentation
The aim of this work was the study of the microbiological profile during “Alheira” fermentation and the subsequent dry smoking process.
Poster
Lactic acid bacteria (LAB) are widely used for the fermentation and preservation of fermented meat products (Tyopponen et al. 2003). Bacteriocins produced by some LAB have inhibitory effects against pathogens and spoilage organisms (Jack et al. 1995). Since food safety has become an increasingly important international concern, the application of a...
Poster
In Portugal epidemiological information regarding listeriosis is scarce. This might be due to the fact that there is no obligatory notification of this foodborne zoonosis in Portugal. However, Listeria monocytogenes has been isolated from different food products throughout various ad hoc studies in our country. One of the most appreciated tradition...
Article
Full-text available
Spray-dried cells of Lactobacillus sakei CTC 494 survived ca. 60% longer in the spray dried state when cells were grown in the presence of 20 g sucrose l(-1) or 12.5 g monosodium glutamate l(-1). No significant differences were observed in viability during storage in the freeze dried state with the addition of these compounds to the growth medium,...
Poster
Enteroccci were isolated from four commercial brands of “alheira”, a traditional fermented sausage produced in the north of Portugal. Gram+ and catalase- organisms isolated in Bile Esculine Azide Agar were tested for growth in 6,5% (w/v) NaCl, at 45ºC and 10ºC and at pH 9.6. Of the 75 presumptive Enterococcus, 45 were further identified as E. faeca...