Biological Hazards BIOHAZ Unit

Parma, Italy

Biological Hazards BIOHAZ Unit

Parma, Italy
Time filter
Source Type

Alvarez-Ordonez A.,University College Cork | Alvarez-Ordonez A.,Alimentary Pharmabiotic Center | Begley M.,University College Cork | Prieto M.,University of León | And 5 more authors.
Microbiology | Year: 2011

Human salmonellosis infections are usually acquired via the food chain as a result of the ability of Salmonella serovars to colonize and persist within the gastrointestinal tract of their hosts. In addition, after food ingestion and in order to cause foodborne disease in humans, Salmonella must be able to resist several deleterious stress conditions which are part of the host defence against infections. This review gives an overview of the main defensive mechanisms involved in the Salmonella response to the extreme acid conditions of the stomach, and the elevated concentrations of bile salts, osmolytes and commensal bacterial metabolites, and the low oxygen tension conditions of the mammalian and avian gastrointestinal tracts. © 2011 SGM.

De Jonghe V.,Belgium Institute for Agricultural and Fisheries Research | Coorevits A.,University College Ghent | Coorevits A.,Ghent University | Van Hoorde K.,University College Ghent | And 7 more authors.
Applied and Environmental Microbiology | Year: 2011

The refrigerated storage of raw milk throughout the dairy chain prior to heat treatment creates selective conditions for growth of psychrotolerant bacteria. These bacteria, mainly belonging to the genus Pseudomonas, are capable of producing thermoresistant extracellular proteases and lipases, which can cause spoilage and structural defects in pasteurized and ultra-high-temperature- treated milk (products). To map the influence of refrigerated storage on the growth of these pseudomonads, milk samples were taken after the first milking turn and incubated laboratory scale at temperatures simulating optimal and suboptimal preprocessing storage conditions. The outgrowth of Pseudomonas members was monitored over time by means of cultivation-independent denaturing gradient gel electrophoresis (DGGE). Isolates were identified by a polyphasic approach. These incubations revealed that outgrowth of Pseudomonas members occurred from the beginning of the dairy chain (farm tank) under both optimal and suboptimal storage conditions. An even greater risk for outgrowth, as indicated by a vast increase of about 2 log CFU per ml raw milk, existed downstream in the chain, especially when raw milk was stored under suboptimal conditions. This difference in Pseudomonas outgrowth between optimal and suboptimal storage was already statistically significant within the farm tank. The predominant taxa were identified as Pseudomonas gessardii, Pseudomonas gessardii-like, Pseudomonas fluorescens-like, Pseudomonas lundensis, Pseudomonas fragi, and Pseudomonas fragi-like. Those taxa show an important spoilage potential as determined on elective media for proteolysis and lipolysis. Copyright © 2011, American Society for Microbiology.

Leuschner R.G.K.,Biological Hazards BIOHAZ Unit | Robinson T.P.,Emerging Risks EMRISK Unit | Hugas M.,Biological Hazards BIOHAZ Unit | Cocconcelli P.S.,Catholic University of the Sacred Heart | And 10 more authors.
Trends in Food Science and Technology | Year: 2010

Qualified Presumption of Safety (QPS) is a generic risk assessment approach applied by the European Food Safety Authority (EFSA) to notified biological agents aiming at simplifying risk assessments across different scientific Panels and Units. The aim of this review is to outline the implementation and value of the QPS assessment for EFSA and to explain its principles such as the unambiguous identity of a taxonomic unit, the body of knowledge including potential safety concerns and how these considerations lead to a list of biological agents recommended for QPS which EFSA keeps updated through an annual scientific review and assessment. © 2010 Elsevier Ltd.

Rasschaert G.,Belgium Institute for Agricultural and Fisheries Research | Piessens V.,Belgium Institute for Agricultural and Fisheries Research | Scheldeman P.,Belgium Institute for Agricultural and Fisheries Research | Leleu S.,Belgium Institute for Agricultural and Fisheries Research | And 5 more authors.
Poultry Science | Year: 2013

Campylobacter is the most commonly reported gastrointestinal bacterial pathogen in humans in many developed countries. During slaughter of broiler flocks, it is difficult to avoid contamination of broiler carcasses. This study aimed to quantify Campylobacter contamination on broiler carcasses at 5 points in the slaughter processing during the slaughter of a Campylobacter- colonized flock by real-time PCR and conventional enumeration. In addition, the decontamination effect of neutral electrolyzed oxidizing (EO) water and 1.5% lactic acid (pH 2.0) were evaluated. During processing, the Campylobacter counts on the carcasses declined toward the end of the processing line. The log counts on the carcasses as determined by quantitative real-time PCR (qPCR), decreased from 9.37 after scalding to 8.08 after the last cooling step. Enumeration of the campylobacters on plates revealed the same trend, although the counts per carcass were generally 3 logs lower. After scalding, a mean of 6.86 log cfu/carcass were counted, which decreased to 4.83 log cfu/carcass after the last cooling step. Submerging carcasses after scalding in EO water gave a significant reduction of 1.31 log cfu/carcass by enumeration on plates and a not significant reduction of 0.53 log cfu/carcass by qPCR. Treatment of the carcasses after the inside-outside bird washer led to reductions from 0.09 to 0.91 log cfu/carcass, although not significant. After submerging the carcasses in a 1.5% lactic acid solution, significant reductions of 1.62 and 1.24 log cfu/carcass by qPCR and enumeration, respectively, were observed. Spraying the carcasses with lactic acid led to nonsignificant reductions of 0.68 log cfu/carcass determined by qPCR and 0.26 log cfu/carcass by enumeration. Both EO water and lactic acid seem promising for implementation in poultry processing plants. © 2013 Poultry Science Association Inc.

Hermans D.,Ghent University | Pasmans F.,Ghent University | Messens W.,Belgium Institute for Agricultural and Fisheries Research | Messens W.,Biological Hazards BIOHAZ Unit | And 7 more authors.
Vector-Borne and Zoonotic Diseases | Year: 2012

Campylobacteriosis is the most reported foodborne gastroenteritic disease and poses a serious health burden in industrialized countries. Disease in humans is mainly caused by the zoonotic pathogen Campylobacter jejuni. Due to its wide-spread occurrence in the environment, the epidemiology of Campylobacter remains poorly understood. It is generally accepted, however, that chickens are a natural host for Campylobacter jejuni, and for Campylobacter spp. in general, and that colonized broiler chicks are the primary vector for transmitting this pathogen to humans. Several potential sources and vectors for transmitting C. jejuni to broiler flocks have been identified. Initially, one or a few broilers can become colonized at an age of >2 weeks until the end of rearing, after which the infection will rapidly spread throughout the entire flock. Such a flock is generally colonized until slaughter and infected birds carry a very high C. jejuni load in their gastrointestinal tract, especially the ceca. This eventually results in contaminated carcasses during processing, which can transmit this pathogen to humans. Recent genetic typing studies showed that chicken isolates can frequently be linked to human clinical cases of Campylobacter enteritis. However, despite the increasing evidence that the chicken reservoir is the number one risk factor for disease in humans, no effective strategy exists to reduce Campylobachter prevalence in poultry flocks, which can in part be explained by the incomplete understanding of the epidemiology of C. jejuni in broiler flocks. As a result, the number of human campylobacteriosis cases associated with the chicken vector remains strikingly high. © 2012, Mary Ann Liebert, Inc.

Leleu S.,Belgium Institute for Agricultural and Fisheries Research | Messens W.,Belgium Institute for Agricultural and Fisheries Research | Messens W.,Biological Hazards BIOHAZ Unit | De Reu K.,Belgium Institute for Agricultural and Fisheries Research | And 6 more authors.
Journal of Food Protection | Year: 2011

Egg washing is currently not permitted within the European Union, with few exceptions. This is mainly because there are concerns that cuticle damage could occur during or after the washing process, as a result of a suboptimal operation. In this study, the cuticle coverage levels of 400 washed or unwashed eggs, derived from either a brown or a white egg-laying flock at the end of lay, were compared. The eggs from older hens inherently have poorer cuticle coverage and as a result arguably constitute a greater risk to consumer safety if they are then washed. Thus, the effects of the washing procedure used in this study on cuticle quality were tested under the worst-case scenario. A standard Swedish egg washing process was used. The cuticle coverage of the eggs was assessed by a colorimeter by quantifying the color difference before and after staining with Tartrazine and Green S. The cuticle of an additional 30 eggs from each of the four groups was then visually assessed by scanning electron microscopy. The staining characteristics of the cuticle varied greatly within each group of eggs and showed that the washing process did not lead to cuticle damage. Scanning electron microscopy confirmed that there was no irreversible damage to the cuticle of the washed eggs and that it was not possible to correctly assign the treatment (washed or not) based on a visual assessment. In conclusion, no evidence could be found to suggest that the washing procedure used in this investigation irreversibly changed the quality of the cuticle. Copyright © International Association for Food Protection.

Leuschner R.G.K.,Biological Hazards BIOHAZ Unit | Hristova A.,Emerging Risks EMRISK Unit | Robinson T.,Emerging Risks EMRISK Unit | Hugas M.,Biological Hazards BIOHAZ Unit
Journal of Food Composition and Analysis | Year: 2013

In the Rapid Alert System for Food and Feed (RASFF) database, an exchange information tool on risk measures related to food and feed controls, notifications concerning the presence of biogenic amines in food are mainly histamine in fish products. This reflects the current EU legislation which sets food safety criteria for histamine in certain fish products. Average histamine concentrations in about 300 notifications between 2002 and 2010 were below 200. mg/kg fish product in 17%, between 200 and 500. mg/kg in 36%, between 500 and 1000. mg/kg in 16%, between 1000 and 2000. mg/kg in 12% and above 2000. mg/kg in 11% of notifications. A high variability of histamine concentrations in different samples originating from the same fish product of up to a factor of 500 was reported. RASFF introduced 'Food poisoning' as a reason for notification in 2008 and reported around 60 negatively affected consumers due to dietary histamine intake until the end of 2010. Based on the evolution and development of notifications in the RASFF database, it can be anticipated that these data will increasingly provide valuable 'real-life' and 'up to date' evidence to support food safety risk analysis in the future. © 2012 Elsevier Inc.

Loading Biological Hazards BIOHAZ Unit collaborators
Loading Biological Hazards BIOHAZ Unit collaborators