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  • A Meta-Analysis on the In Vitro Antagonistic Effects of Lactic Acid Bacteria from Dairy Products on Foodborne Pathogens
    Publication . Loforte, Yara; Fernandes, Nathália; Almeida, André Martinho de; Cadavez, Vasco; Gonzales-Barron, Ursula
    Raw milk and traditional fermented foods such as artisanal cheese represent a natural source of lactic acid bacteria (LAB). They can produce antimicrobial compounds, such as bacteriocins and lactic acid, which may be exploited in dairy biopreservation. This study aimed to conduct a systematic review and meta-analysis to synthesize the inhibition diameter (ID) of LAB against L. monocytogenes, S. aureus, and Salmonella spp. Literature electronic searches were performed on PubMed, Scopus, and Web of Science, to identify articles that reported data on in-vitro antimicrobial activity by LAB isolated from dairy foods. A total of 1665 papers were retrieved, and 20 primary studies were selected according to the selection criteria, of which 397 observations were extracted. Random-effects meta-regression models were employed to describe the effects of LAB genus, pathogen concentration, susceptibility method, incubation time, inoculation volume, agar type and pH on the IDs for L. monocytogens, S. aureus, and Salmonella spp. L. monocytogens was the most susceptible pathogen (p < 0.05) to the LAB effects, followed by S. aureus and Salmonella spp. As a whole, LAB from the Lacticaseibacillus genus were the most effective (p < 0.05) in inhibiting L. monocytogens (21.49 ± 2.654 mm), followed by S. aureus (21.06 ± 2.056 mm). Salmonella spp. presented higher (p < 0.05) susceptibility to Lactobacillus genus (19.93 ± 2.456 mm). From the results, a general trend could be observed for the well-diffusion method to produce higher (p < 0.05) ID estimates than the spot and disk methods (30.73 ± 2.530 mm vs. 21.98 ± 1.309 mm vs. 13.39 ± 1.403 mm for L. monocytogenes; 22.37 ± 1.073 mm vs. 14.91 ± 2.312 mm vs. 20.30 ± 2.319 mm for Salmonella spp.), respectively. Among the tested moderators, the pathogen’s inoculum concentration, the in vitro susceptibility assay itself, incubation time and inoculation volume on agar are determinant parameters to be looked at when designing a robust and reproducible experimental plan. The in vitro results reinforced that LAB can be useful in controlling the development of pathogenic bacteria frequently found in the dairy industry.
  • Meta-análise do contato com animais como rota de transmissão de toxoplasmose esporádica
    Publication . Rodrigues, Vânia; Cadavez, Vasco; Kooh, Pauline; Sanaa, Moez; Gonzales-Barron, Ursula; Rodrigues, Vânia
    A toxoplasmose é uma infeção causada pelo parasita Toxoplasma gondii, cuja transmissão ocorre por ingestão de alimentos contaminados, contato com animais (zoonose) e de mãe para filho (congénita). O objetivo deste estudo foi sintetizar a associação entre a infeção esporádica por T. gondii e o contato com animais, através da combinação dos resultados de estudos de caso-controlo relevantes, usando a meta-análise para produzir uma estimativa mais precisa da associação global entre o fator de risco e a doença.
  • Meta-análise do contato com animais e do consumo de carne como fontes de salmonelose esporádica
    Publication . Gonçalves-Tenório, Andiara; Cadavez, Vasco; Rodrigues, Vânia; Kooh, Pauline; Sanaa, Moez; Gonzales-Barron, Ursula; Rodrigues, Vânia
    As doenças gastrointestinais representam um importante problema de saúde pública em todo mundo, desta forma a identificação da origem de transmissão é de grande importância para a avaliação e atribuição de risco. Os estudos epidemiológicos de casocontrolo são usados para identificar os fatores de risco associados à transmissão das doenças. A salmonelose, doença causada por vários serotipos de Salmonella spp., pode ser transmitida ao homem de diversas formas. De uma forma geral, os casos esporádicos de salmonelose não partilham o mesmo fator de risco ou rota de contaminação, de modo que os estudos que medem a relação de probabilidades (“odds ratio”, OR) de qualquer fonte de transmissão podem ocultar os riscos reais tornando-os mais difíceis de detetar (Fullerton et al., 2012). Por exemplo, o frango assado é uma importante fonte de contaminação por Salmonella spp., todavia a maioria das porções de frango não estão contaminadas, de modo que a probabilidade de uma pessoa adquirir salmonelose pelo consumo de frango assado é apenas um pouco superior à das pessoas que não consomem frango assado (controlo).
  • Controlling Listeria monocytogenes contamination in fresh goat milk cheeses: Dynamic modelling during storage
    Publication . Bonilla-Luque, Olga María; Possas, Arícia; Gonzales-Barron, Ursula; Cadavez, Vasco; Ezzaky, Youssef; Hussein, Abdelraheem; Valero, Antonio
    Predictive models applied for artisanal fresh goat cheeses are invaluable tools for rapid decision-making in quality and safety management. Listeria monocytogenes is a common foodborne pathogen associated with recent safety alerts in ready-to-eat (RTE) products in Andalucia. Managing artisanal production variables, such as storage conditions and final product features (pH or water activity [aw]) might be crucial for controlling L. monocytogenes in these traditional products. This study evaluated the time-temperature dependence of L. monocytogenes during shelf-life of fresh goat milk cheese artisanally produced in Andalucía. The effect of storage temperature (4–25 ◦C) over 5–20 days was tested in lab-scale fresh goat milk cheeses initially inoculated with a three-strain cocktail of the pathogen (ca. 2–3 log cfu/g). The Huang (model A) and Baranyi (model B) models coupled with Ratkowsky were fitted to the collected growth data to describe the relationship between L. monocytogenes concentration, growth rate (μmax, log cfu/d), storage temperature, and time. The results highlighted the higher variability of growth data at 4 ◦C, the linear relationship between μmax and temperature, the inverse correlation between ymax (exceeding 5 log cfu/g at all the temperatures) and ΔY (with a maximum of 4.386 and minimum of 2.461, at 4 and 25 ◦C, respectively) and a faster decrease of pH at higher temperatures. Model validity, assessed through goodness-of-fit and both internal and external validations (under both isothermal temperatures and a dynamic temperature workflow simulating real production scenario), revealed good model adjustment to L. monocytogenes growth in artisanal commercial cheeses, after determining a correction factor of 1.806 and 1.856, for models A and B, respectively. Predictions indicated that an initially contaminated artisanal fresh goat milk cheese would not meet regulatory limits after 4 days under refrigeration conditions (4 ◦C), aerobic conditions, or opened packaging. These results highlight the potential public health risk of artisanal fresh goat milk cheeses related to L. monocytogenes transmission if manufacturing and storage conditions are not well controlled, emphasizing the need for stringent microbial control efforts and mitigation measures.
  • Predicción in vivo de la composición de la canal: técnica de los ultrasonidos y puntuación de la condición corporal.
    Publication . Delfa, Rafael; Teixeira, Alfredo; Cadavez, Vasco; Sierra-Alfancra, I
    En una detallada monografía sobre la calidad de la canal ovina. Delfa (1992a) y Delfa el al. (J 992a) exponían que la valoración de la composición de la canal, es decir, la determinación de la proporción de piezas que de ella se obtienen así como de la cantidad absoluta o relativa del musculo. grasa y hueso que cada una de las piezas proporcionan y el reparto y distribución del tejido adiposo en la canal. Son los criterios más importantes que dilucidan la calidad de las mismas.
  • Pathogens-in-Foods (PIF): An open-access European database of occurrence data of biological hazards in foods
    Publication . Gonzales-Barron, Ursula; Faria, Ana Sofia; Thebault, Anne; Guillier, Laurent; Mendes, Lucas Ribeiro; Silva, Lucas Ribeiro; Messens, Winy; Kooh, Pauline; Cadavez, Vasco
    The collection of occurrence data of foodborne pathogens in foods faces the hindrances of dispersion of information, lack of standardisation and harmonisation, and ultimately, high expenditure in time and resources. The Pathogens-in-Foods (PIF) database was conceived as a solution to centralise published data on prevalence and concentration of pathogenic bacteria, viruses and parasites occurring in foods, obtained through systematic review (SR), and categorised in harmonised data structures under controlled terminologies. The present article outlines how PIF was constructed to adhere to the FAIR (findability, accessibility, interoperability and reusability) principles for scientific data management; and proceeds with a description of the PIF concept, which entails two phases: the SR process and the population of PIF. The protocolled SR process is supported by a welldefined search strategy, inclusion criteria, and rules for internal validation assessment; whereas the population of PIF with new data relies in data extraction, validation and release. The article then introduces a novel data quality approach, named as the CCC approach (data consistency, conformity and completeness), which ensures proper interpretation of data, richness of data, and flawless transcription of data. After a brief explanation of the three PIF components – database, back-end and front-end – the article proceeds with the exposition of the data model, as well as the capabilities of the front-end, including data search, insertion and curation. The future of PIF lies in expanding its capabilities, addressing emerging challenges, and leveraging technological advancements to maintain its relevance and utility in the evolving landscape of food safety.
  • Hierarquização dos factores de risco associados à salmonelose por meta-análise de estudos caso-controlo
    Publication . Rodrigues, Vânia; Cadavez, Vasco; Gonzales-Barron, Ursula; Kooh, Pauline; Sanaa, Moez; Rodrigues, Vânia
    Os estudos caso-controlo são uma metodologia de investigação em epidemiologia que permitem analisar, de forma retrospectiva, a exposição a factores de risco das doenças entéricas. O objectivo deste trabalho foi sintetizar a associação entre as infecções esporádicas por Salmonella spp. e os factores de risco, através da combinação dos resultados de estudos casocontrolo. Para uniformizar as categorias de exposição, desenvolvemos uma classificação dos eventuais factores de risco, com as seguintes categorias: viagem, especificidades do hospedeiro, transmissão de pessoa a pessoa, contacto com animais, contaminação pelo ambiente e consumo de alimentos. A pesquisa da literatura relevante foi realizada através dos portais da Science Direct, Pubmed, Scielo, 151 Web of Science e Scopus. Em cada estudo caso-controlo, foi recolhida a medida de associação oddsratio (ORs) da doença com a exposição. Os estudos seleccionados foram classificados quanto ao seu potencial de enviesamento, resultante de deficiências do desenho experimental, da selecção da população e dos métodos utilizados na análise dos dados. Foram também extraídas outras características consideradas importantes, tais como: a população, o desenho experimental, a análise estatística dos dados e o(s) factor(es) de risco. Posteriormente, os ORs globais, para cada factor de risco e das rotas de transmissão, foram estimados por modelos de meta-análise com o software R, e hierarquizados.
  • Microbiological safety of goat milk and cheese: evidences from a meta-analysis
    Publication . Cadavez, Vasco; Rodrigues, Vânia; Gonzales-Barron, Ursula; Rodrigues, Vânia
    This chapter synthesizes published information concerning the incidence of zoonotic pathogenic microorganisms – Listeria monocytogenes, Staphylococcus aureus and shigatoxin-producing Escherichia coli – in raw goat milk and cheese. Meta-analytical data were extracted from primary studies undertaken in Brazil, China, Czech Republic, Germany, Iran, Italy, Malaysia, Mexico, Norway, Portugal, Spain, Sweden, Switzerland, Turkey and USA. In both raw goat milk (overall incidence 42.6%; 95% CI: 23.0-64.8%) and cheese (overall incidence 26.4%; 95% CI: 10.8-51.6%), S. aureus was found to be the most frequent contaminant bacterium, which suggests that control measures during milk handling are still to be reinforced. In addition, the high frequency of detection of generic E. coli in raw goat milk cheese (overall incidence 11.9%; 95% CI: 3.8- 31.6%) is another indicator of hygiene deficiencies during production. Moreover, E. coli strains with virulence genes have been very frequently detected in raw goat milk (overall incidence 10.5%; 95% CI: 5.3–19.6%). L. monocytogenes, a pathogen that mainly affects the susceptible population, presented a high incidence in both raw goat milk (overall incidence 3.4%; 95% CI: 2.2-5.1%) and goat milk cheese (overall incidence 8.5%; 95% CI: 4.9-14.6%). In conclusion, the present meta-analysis confirms that raw goat milk and cheese are important vehicles of transmission of food-borne diseases. Further research work towards improving the current microbiological quality of these products, particularly in traditional production units, is essential.
  • Meta-análise do contato com animais e do consumo de carne como fontes de salmonelose esporádica
    Publication . Gonçalves-Tenório, Andiara; Cadavez, Vasco; Rodrigues, Vânia; Kooh, Pauline; Sanaa, Moez; Gonzales-Barron, Ursula; Rodrigues, Vânia
    As doenças gastrointestinais representam um importante problema de saúde pública em todo mundo, desta forma a identificação da origem de transmissão é de grande importância para a avaliação e atribuição de risco. Os estudos epidemiológicos de casocontrolo são usados para identificar os fatores de risco associados à transmissão das doenças. A salmonelose, doença causada por vários serotipos de Salmonella spp., pode ser transmitida ao homem de diversas formas. De uma forma geral, os casos esporádicos de salmonelose não partilham o mesmo fator de risco ou rota de contaminação, de modo que os estudos que medem a relação de probabilidades (“odds ratio”, OR) de qualquer fonte de transmissão podem ocultar os riscos reais tornando-os mais difíceis de detetar (Fullerton et al., 2012). Por exemplo, o frango assado é uma importante fonte de contaminação por Salmonella spp., todavia a maioria das porções de frango não estão contaminadas, de modo que a probabilidade de uma pessoa adquirir salmonelose pelo consumo de frango assado é apenas um pouco superior à das pessoas que não consomem frango assado (controlo).
  • Food source atribution of human campylobacteriosis by meta-analysis of case-control studies
    Publication . Rodrigues, Vânia; Cadavez, Vasco; Kooh, Pauline; Moez, Sanna; Gonzales-Barron, Ursula; Rodrigues, Vânia
    A case-control study is a powerful approach among epidemiologists to investigate the causal effect of exposure and enteric illness. To combine the associations between sporadic campylobacteriosis and the different food pathways of exposure, the results from relevant case-control studies were extracted and their odds-ratio (OR) measures were meta-analysed within food category partitions by population type, extracting the variability due to both primary studies and model types. In the mixed population, the most important determinants of disease turned out to be: consumption of raw milk (pooted OR=2. 64), poultry (OR=1. 78), raw milk's cheese (OR=1. 72), BBQ meats (OR=1. 67), fast-food composite (OR=1. 59) and raw seafood (OR=1. 50). On the other hand, consumption of raw-egg containing products (OR=4. 85), raw milk (OR=3. 05), pork (OR=2. 34), minced beef (OR=2.27), processed meats (OR=2.18), any composite food eaten out (OR=2.16) and poultry meat (OR=2.08) were found to bear the highest risk of campylobacteriosis in the children population.