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We describe the prototype of an electronic tool for risk assessment with dynamic ranking of wildlife-borne pathogens in function of their need for surveillance. Data about pathogens, their hosts and occurrences are obtained from literature and are classified as qualitative scores under six main criteria with their sub-criteria, corresponding to the elements of a standard risk assessment. Pathogen-specific data are reviewed by experts. The information is processed per pathogen through an algorithm and through summing up of the values obtained by converting four-tiered qualitative sub-criteria scores to weighted five-tiered numerical values. For a consistent comparison between pathogens, the 'unknown' sub-criteria scores are assigned a median value of 3, allowing preservation of the sub-criteria concerned and their weights for the risk assessment, but minimizing the effect of this score on the outcome. Irregular data availability is further accommodated by a different data processing for comprehensiveness and refinement requirements, which is realised by a respective first- and second-level ranking of pathogens, the latter using additional quantitative and qualitative data for the release assessment. Continuous data updates are necessary to reflect the current situation in the field. Output flexibility is implemented by the possibility to run queries based on the choice of a region, a specific target group susceptible to the pathogens and a set of weights for the sub-criteria. [ABSTRACT FROM AUTHOR]

Esophageal adenocarcinoma (EAC) is an aggressive cancer characterized by a high risk of relapse post-surgery. Current follow-up methods (serum carcinoembryonic antigen detection and PET-CT) lack sensitivity and reliability, necessitating a novel approach. Analyzing cell-free DNA (cfDNA) from blood plasma emerges as a promising avenue. This study aims to evaluate the cost-effective and genome-wide cell-free reduced representation bisulfite sequencing (cfRRBS) method combined with computational deconvolution for effective disease monitoring in EAC patients. cfDNA methylation profiling with cfRRBS was performed on 162 blood plasma samples from 33 EAC cancer patients and 28 blood plasma samples from 20 healthy donors. The estimated tumor fraction for EAC patients at the time of diagnosis was significantly different from the healthy donor plasma samples (one-sided Wilcoxon rank-sum test: p-value = 0.032). Tumor fractions above 15% and focal gains/amplifications in MYC (chr8), KRAS (chr12), EGFR (chr7) and NOTCH2 (chr1) were observed in four samples of distinct patients at the time metastatic disease was detected. This study showed feasibility to estimate tumor fractions in blood plasma of EAC patients based on cfDNA methylation using cfRRBS and computational deconvolution. Nevertheless, in this study only cancer patients with evidence of metastatic disease show high tumor fractions and copy number alterations., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Ethics: Written informed consent was obtained from all cancer patients and healthy donors. Sample collection was approved by the ethics committee of Ghent University Hospital (registration numbers B670201628317, B670201628319 and B670201733701). The research was conducted according to the local legislation and institutional requirements., (© 2024. The Author(s).)

Transcriptomic profiling of blood immune cells offers a promising alternative to invasive, sampling bias-prone tissue-based biomarker assays for predicting immune checkpoint inhibitor (ICI) therapy response in non-small cell lung cancer (NSCLC) patients. However, the optimal analytical approach to identify systemic correlates of response still needs to be explored. We collected peripheral blood mononuclear cells and whole blood (WB) samples from 33 ICI-treated NSCLC patients before ICI treatment and at the first response evaluation. After bulk polyadenylated RNA-sequencing, we assessed differences in gene expression profiles between non-responders and responders using differential expression analysis, single sample gene set enrichment analysis (ssGSEA), and cell type deconvolution. We evaluated gene expression values, ssGSEA scores, and deconvolved cell type proportions to distinguish non-responders from responders via ROC curve (AUC) analysis, training a logistic regression classification model. Gene expression values and deconvolved proportions yielded the best results with WB samples after treatment (AUC = 0.87 and 0.85, respectively). Overall, ssGSEA scores showed superior classification performance across all sample types and timepoints (AUC > 0.7). In conclusion, transcriptomic analysis through ssGSEA demonstrated the best performance as a non-invasive biomarker for predicting clinical benefit in ICI-treated NSCLC patients, with gene expression and deconvolution on post-treatment WB samples also showing promising results., (© 2024. The Author(s).)

Neuroblastoma, a rare embryonic tumor arising from neural crest development, is responsible for 15% of pediatric cancer-related deaths. Recently, several single-cell transcriptome studies were performed on neuroblastoma patient samples to investigate the cell of origin and tumor heterogeneity. However, these individual studies involved a small number of tumors and cells, limiting the conclusions that could be drawn. To overcome this limitation, we integrated seven single-cell or single-nucleus datasets into a harmonized cell atlas covering 362,991 cells across 61 patients. We use this atlas to decipher the transcriptional landscape of neuroblastoma at single-cell resolution, revealing associations between transcriptomic profiles and clinical outcomes within the tumor compartment. In addition, we characterize the complex immune-cell landscape and uncover considerable heterogeneity among tumor-associated macrophages. Finally, we showcase the utility of our atlas as a resource by expanding it with additional data and using it as a reference for data-driven cell-type annotation., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Currently, we cannot provide a conclusive diagnosis for 3% to 5% of people who are confronted with cancer. These patients have cancer of unknown primary (CUP), ie, a metastasized cancer for which the tissue of origin cannot be determined. Studies have shown that the DNA methylation profile is a unique "fingerprint" that can be used to classify tumors. Here we used cell-free reduced representation bisulfite sequencing (cfRRBS), a technique that allows us to identify the methylation profile starting from minimal amounts of highly fragmented DNA, for CUP diagnosis on formalin-fixed paraffin-embedded (FFPE) tissue and liquid biopsies. We collected 80 primary tumor FFPE samples covering 16 tumor entities together with 15 healthy plasma samples to use as a custom cfRRBS reference data set. Entity-specific methylation regions are defined for each entity to build a classifier based on nonnegative least squares deconvolution. This classification framework was tested on 30 FFPE, 19 plasma, and 40 pleural and peritoneal effusion samples of both known metastatic tumors and clinical CUPs for which pathological investigation finally resulted in a cancer diagnosis. Using this framework, 27 of 30 FFPE (all CUPs) and 16 of 19 plasma samples (10/13 CUPs) obtained an accurate diagnosis, with a minimal DNA input of 400 pg. Diagnosis of the 40 pleural and peritoneal effusion samples is possible in 9 of 27 samples with negative/inconclusive cytology (6/13 CUPs), showing that cell-free DNA (cfDNA) methylation profiling could complement routine cytologic analysis. However, a low "cfDNA - high-molecular weight DNA ratio" has a considerable impact on the prediction accuracy. Moreover, the accuracy improves significantly if the predicted tumor percentage is >7%. This proof-of-concept study shows the feasibility of using DNA methylation profiling on FFPE and liquid biopsy samples such as blood, ascites, and pleural effusions in a fast and affordable way. Our novel RRBS-based technique requires minimal DNA input, can be performed in <1 week, and is highly adaptable to specific diagnostic problems as we only use 5 FFPE references per tumor entity. We believe that cfRRBS methylation profiling could be a valuable addition to the pathologist's toolbox in the diagnosis of CUPs., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Pediatric central nervous system tumors remain challenging to diagnose. Imaging approaches do not provide sufficient detail to discriminate between different tumor types, while the histopathological examination of tumor tissue shows high inter-observer variability. Recent studies have demonstrated the accurate classification of central nervous system tumors based on the DNA methylation profile of a tumor biopsy. However, a brain biopsy holds significant risk of bleeding and damaging the surrounding tissues. Liquid biopsy approaches analyzing circulating tumor DNA show high potential as an alternative and less invasive tool to study the DNA methylation pattern of tumors. Here, we explore the potential of classifying pediatric brain tumors based on methylation profiling of the circulating cell-free DNA (cfDNA) in cerebrospinal fluid (CSF). For this proof-of-concept study, we collected cerebrospinal fluid samples from 19 pediatric brain cancer patients via a ventricular drain placed for reasons of increased intracranial pressure. Analyses on the cfDNA showed high variability of cfDNA quantities across patients ranging from levels below the limit of quantification to 40 ng cfDNA per milliliter of CSF. Classification based on methylation profiling of cfDNA from CSF was correct for 7 out of 20 samples in our cohort. Accurate results were mostly observed in samples of high quality, more specifically those with limited high molecular weight DNA contamination. Interestingly, we show that centrifugation of the CSF prior to processing increases the fraction of fragmented cfDNA to high molecular weight DNA. In addition, classification was mostly correct for samples with high tumoral cfDNA fraction as estimated by computational deconvolution (> 40%). In summary, analysis of cfDNA in the CSF shows potential as a tool for diagnosing pediatric nervous system tumors especially in patients with high levels of tumoral cfDNA in the CSF. Further optimization of the collection procedure, experimental workflow and bioinformatic approach is required to also allow classification for patients with low tumoral fractions in the CSF., (© 2024. The Author(s).)

Background: Blood plasma, one of the most studied liquid biopsies, contains various molecules that have biomarker potential for cancer detection, including cell-free DNA (cfDNA) and cell-free RNA (cfRNA). As the vast majority of cell-free nucleic acids in circulation are non-cancerous, a laboratory workflow with a high detection sensitivity of tumor-derived nucleic acids is a prerequisite for precision oncology. One way to meet this requirement is by the combined analysis of cfDNA and cfRNA from the same liquid biopsy sample. So far, no study has systematically compared the performance of cfDNA and cfRNA co-purification to increase sensitivity., Results: First, we set up a framework using digital PCR (dPCR) technology to quantify cfDNA and cfRNA from human blood plasma in order to compare cfDNA/cfRNA co-purification kit performance. To that end, we optimized two dPCR duplex assays, designed to quantify both cfDNA and cfRNA with the same assays, by ensuring that primers and probes are located within a highly abundant exon. Next, we applied our optimized workflow to evaluate the co-purification performance of two manual and two semi-automated methods over a range of plasma input volumes (0.06-4 mL). Some kits result in higher nucleic acid concentrations in the eluate, while consuming only half of the plasma volume. The combined nucleic acid quantification systematically results in higher nucleic acid concentrations as compared to a parallel quantification of cfDNA and cfRNA in the eluate., Conclusions: We provide a framework to evaluate the performance of cfDNA/cfRNA co-purification kits and have tested two manual and two semi-automated co-purification kits in function of the available plasma input amount and the intended use of the nucleic acid eluate. We demonstrate that the combined quantification of cfDNA and cfRNA has a benefit compared to separate quantification. We foresee that the results of this study are instrumental for clinical applications to help increase mutation detection sensitivity, allowing improved disease detection and monitoring., (© 2022. The Author(s).)

Objectives: The aim of this Belgian research study was to describe the characteristics of physicians who are at increased risk for patient-physician aggression. Second, aggression subtypes were described and data were provided on the prevalence of patient-physician aggression in Belgium., Design: Cross-sectional survey., Setting: Primary and secondary care inside and outside hospitals., Participants: Any physician who had worked in Belgium for the preceding 12 months was eligible to participate (n=34 648)., Main Outcome Measures: An online, original questionnaire was used to obtain physician characteristics (eg, age, sex, native language), department, working conditions and contact with aggressive patients during their career and during the preceding 12 months., Results: The questionnaire was completed by 4930 participants and 3726 (76%) were valid to take into account for statistics. During the preceding 12 months, 37% had been victims of aggression: 33% experienced verbal aggression, 30% psychological, 14% physical and 10% sexual. Multiple answers were allowed. Women and younger physicians were more likely to experience aggression. Psychiatric departments and emergency departments were the settings most commonly associated with aggression. Physicians who provided primarily outpatient care were more subject to aggression., Conclusion: Belgian physicians experience several forms of aggression. Those most at-risk of aggression are young and female physicians who work in outpatient, emergency or psychiatric settings., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

In a cross-sectional field study involving 51 cattle herds in Belgium, 3159 serum samples and 557 individual milk samples were collected and tested by four different commercial antibody (Ab) ELISAs on serum and two Ab ELISAs on milk. A virus neutralization test (VNT) was performed on serum samples with discording ELISA results and on all samples from non-vaccinating herds. An epidemiological survey was carried out in the same herds to collect information about herd characteristics, management practices, BVD vaccination and BVD infection status. The objective of the study was to evaluate the performances of the Ab ELISAs relatively to the VNT, to assess the possibility of using pooled samples and to give recommendations regarding serological monitoring of BVD-free herds in the context of the Belgian national BVD eradication program which started early 2015. Depending on the assays, for ELISAs on serum, the diagnostic sensitivity (DSe) was estimated to be between 93.0 and 98.7% and the diagnostic specificity (DSp) between 94.3% and 99.1%. For the two ELISAs on milk, the DSe were 91.3% and 96.7% and the DSp 94.0% and 100% respectively and the Cohen's agreement coefficients between serum and milk samples were 0.75 and 0.85. Positive serum and milk samples diluted in negative samples to mimic different pool sizes were not detected by all ELISAs at dilutions above 1:5 or 1:10, leading to the conclusion that the testing of pooled samples should be used cautiously for serological monitoring and only with ELISAs with high sensitivity. The epidemiological analysis and the seroprevalence study, based on a general estimating equation model, showed that several factors had a significant influence on overall animal seroprevalence and within-herd seroprevalence such as age class, herd size, BVD herd infection status, BVD vaccination of young and/or adult cattle and the number of stables in the farm. This study showed that the best performances obtained with commercial Ab ELISAs are observed on individual serum samples, which should therefore be the preferred matrix to monitor BVD-free herds in the context of the Belgian eradication program. By regularly testing a limited number of samples from young (6-18 months) unvaccinated cattle it is possible to confirm the BVD-free herd status or to detect a recent infection., (Copyright © 2018 Elsevier B.V. All rights reserved.)

We performed a thorough fit-for-purpose evaluation of commercial ELISAs for the detection of bovine viral diarrhea virus (BVDV)-specific antibodies in serum and in milk by testing 2 panels of well-characterized serum and milk samples. Sixteen ELISAs from 9 different manufacturers, available on the Belgian market at the time of our study, were assessed for their diagnostic and analytical sensitivity (DSe and ASe, respectively), diagnostic specificity (DSp), and repeatability relative to the virus neutralization (VN) test considered to be the gold standard assay. Using serum as a matrix, DSe was much lower for competitive (c)ELISAs (min. 45%, max. 65%) than for indirect (i)ELISAs (min. 85%, max. 100%), partly because of the lower detection of positive samples from vaccinated animals included in the panel. ASe was also better for iELISAs; DSp was >95% for all but 2 ELISAs. Repeatability, expressed as coefficients of variation (CV) of optical densities, was generally good, although 3 ELISAs had a mean CV >10%. With milk samples, as observed for serum, DSe was lower for cELISAs (min. 57%, max. 75%) than for iELISAs (min. 61%, max. 89%), and DSp was high for all ELISAs (min. 94%, max. 100%). Both DSe and ASe were lower when testing milk samples compared to serum samples. These results confirm that serologic monitoring of BVDV-free herds should be performed using serum samples of unvaccinated animals to avoid interference of vaccination and to maximize the chance of detecting seroconversion linked to BVDV infection. Further investigations using a larger collection of field samples are recommended.

Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (Map), is a chronic granulomatous enteritis which primarily affects domestic and wild ruminants, resulting in serious economic losses for dairy and beef industry around the world. There is no satisfactory cure or vaccine, and actual diagnostic tests need improvement, particularly for the initial stages of the disease. Map specific cell-mediated immune responses may allow early detection of the infection at subclinical stages. In this study, over a period of 39 months, we collected 548 blood samples in two culture-confirmed Map-infected herds, 95 blood samples in five dairy herds that scored negative during 3 consecutive years of Map serology testing and 79 samples in three culture-confirmed M. bovis infected herds. Based on criteria of bacteriology, serology and ratio of IFN-γ induced with bovine and avian purified protein derivative of tuberculin (PPD-B/PPD-A), we classified the samples in four groups: 415 samples as Map-exposed/infected (MAP), 58 samples as aspecific reactors (AR), 179 samples as non-responders (NI) and 70 samples as M. bovis infected (TB). Age of the animals influenced the IFN-γ response in the MAP group, with PPD specific IFN-γ levels (but not PPD-B/PPD-A IFN-γ ratio) being significantly higher in animals <18 months of age. Map specific antibodies were detected by IDEXX ELISA in 13/415 (3%) sera of the MAP group, whereas fecal culture was positive for only 7/405 (1.7%) samples. Animals in the MAP group could therefore be considered being at the very early stage of Map infection. Six purified, recombinant Map antigens (Ag5, Ag6, MAP1637c, MAP0388, MAP3547c and MAP0586c), previously identified using combined advanced proteomic or reverse genomic approaches, were tested for their diagnostic potential in a 20h IFN-γ release assay. In the age group >18 months old, Ag5 and MAP0388 were recognized by only 10.1% and 7.7% of the animals in the MAP group, whereas a total of 38.6.%, 29.4%, 25.6% and 39.0% of the animals in the MAP group reacted to Ag6, MAP1637c, MAP3547c and MAP0586c respectively. None of the animals in the TB group reacted to Ag6, MAP1637c or MAP586c. Except for MAP0388, the % of reactors in the MAP group was significantly higher in animals <18 months old: 28.0%, 24.0%, 45.5%, 47.1%, 49.8% and 47.4% respectively. Further studies of these candidates and their combination are needed to confirm their diagnostic potential for the detection of early Map infection., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In the frame of a Flemish wildlife surveillance in 2013, a serological screening was performed on sera from wild boar (Sus scrofa; n=238) in order to detect tick-borne encephalitis virus (TBEV)-specific antibodies. Neutralising antibodies were titrated with a seroneutralisation test (SNT), using two cut-off titres (1/10-1/15). Seven wild boars were found TBEV-seropositive and showed moderate (>1/15) to high (>1/125) SNT-titres; three individuals had borderline results (1/10-1/15). This study demonstrated the presence of TBEV-specific antibodies in wild boar and highlighted potential TBEV-foci in Flanders. Additional surveillance including direct virus testing is now recommended.

Introduction: In order to investigate the role of roe deer in the maintenance and transmission of infectious animal and human diseases in Flanders, we conducted a serologic screening in 12 hunting areas., Materials and Methods: Roe deer sera collected between 2008 and 2013 (n=190) were examined for antibodies against 13 infectious agents, using indirect enzyme-linked immunosorbent assay, virus neutralisation, immunofluorescence, or microagglutination test, depending on the agent., Results and Discussion: High numbers of seropositives were found for Anaplasma phagocytophilum (45.8%), Toxoplasma gondii (43.2%) and Schmallenberg virus (27.9%), the latter with a distinct temporal distribution pattern following the outbreak in domestic ruminants. Lower antibody prevalence was found for Chlamydia abortus (6.7%), tick-borne encephalitis virus (5.1%), Neospora caninum (4.8%), and Mycobacterium avium subsp paratuberculosis (4.1%). The lowest prevalences were found for Leptospira (1.7%), bovine viral diarrhoea virus 1 (1.3%), and Coxiella burnetii (1.2%). No antibodies were found against Brucella sp., bovine herpesvirus 1, and bluetongue virus. A significant difference in seroprevalence between ages (higher in adults >1 year) was found for N. caninum. Four doubtful reacting sera accounted for a significant difference in seroprevalence between sexes for C. abortus (higher in females)., Conclusions: Despite the more intensive landscape use in Flanders, the results are consistent with other European studies. Apart from maintaining C. abortus and MAP, roe deer do not seem to play an important role in the epidemiology of the examined zoonotic and domestic animal pathogens. Nevertheless, their meaning as sentinels should not be neglected in the absence of other wild cervid species.

In a multi-disciplinary effort, we investigate the level of speckle that can be tolerated in a laser cinema projector based on a quality of experience experiment with movie clips shown to a test audience in a real-life movie theatre setting. We identify a speckle disturbance threshold by statistically analyzing the observers' responses for different values of the amount of speckle, which was monitored using a well-defined speckle measurement method. The analysis shows that the speckle perception of a human observer is not only dependent on the objectively measured amount of speckle, but it is also strongly influenced by the image content. The speckle disturbance limit for movies turns out to be substantially larger than that for still images, and hence is easier to attain.

Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, whereas in the test group solid feed was provided. Maternal antibodies for alpha toxin were present in 45% of the veal calves and 66% of the beef calves. In beef calves a fluent transition from maternal to active immunity was observed for alpha toxin, whereas almost no veal calves developed active immunity. Perfringolysin antibodies significantly declined both in veal and beef calves. In the second study all calves were seropositive for alpha toxin throughout the experiment and solid feed intake did not alter the dynamics of alpha and perfringolysin antibodies. In conclusion, the present study showed that veal calves on a traditional milk replacer diet had significantly lower alpha toxin antibodies compared to beef calves in the risk period for enterotoxaemia, whereas no differences were noticed for perfringolysin.

Failure of passive transfer is a common problem in calves destined for veal production. At present it is unknown whether the risk for respiratory disease (BRD) or neonatal calf diarrhea (NCD) in the veal herd is associated with total immunoglobulin (Ig) and/or on the serostatus for respiratory pathogens measured at arrival. Therefore, the first objective of this prospective longitudinal cohort study was to determine associations between serum protein fractions as determined by routine electrophoresis (total protein, albumin, alpha-1 and -2 globulins, beta-globulins and Ig's) at arrival and BRD and NCD in the first 3 weeks of the production cycle. The second objective was to determine whether the serostatus (seropositive/seronegative) of seven respiratory pathogens (bovine respiratory syncytial virus (BRSV), parainfluenzavirus-3, bovine coronavirus (BCV), bovine herpesvirus-1, bovine viral diarrhea virus, Mannheimia haemolytica and Mycoplasma bovis) of these arrival serum samples could be associated with the risk of having BRD. The third objective was to determine which of the electrophoresis proteins and respiratory serostatuses were associated with average daily gain (ADG) in the study period. The study population consisted of 150 rosé veal calves housed in a single air-space. The study period ended at day 18 post arrival, when BRD incidence was judged to be too high to further postpone a group treatment. A Cox regression model was used to determine the effect of the studied protein fractions and antibodies on the time to BRD and NCD occurrence. The effect of the studied predictors on ADG was determined by linear regression. Calves with Ig levels under 7.5g/L had an increased BRD hazard (hazard ratio (HR)=1.9 (95% confidence interval (CI)=1.2-3.0)). NCD was only positively associated with the alpha-2 globulin concentration. Calves with a negative serostatus for BCV (HR=1.7 (95% CI=1.0-2.8)) or BRSV (HR=2.0 (95% CI=1.0-3.9)) had an increased BRD hazard. Average daily gain (ADG) was 0.242kg/day (SD=0.142) and was not related to the occurrence of BRD or NCD. Calves with Ig's below 7.5g/L and with increased levels of alpha-2 globulins showed a decrease in ADG. This study showed the importance of providing sufficient colostrum to veal calves and the potential benefit of the presence of BCV and BRSV antibodies at arrival to reduce the BRD hazard in the first 3 weeks., (Copyright © 2015 Elsevier B.V. All rights reserved.)

We study the perception of speckle by human observers in a laser projector based on a 40 persons survey. The speckle contrast is first objectively measured making use of a well-defined speckle measurement method. We statistically analyse the results of the user quality scores, revealing that the speckle perception is not only influenced by the speckle contrast settings of the projector, but it is also strongly influenced by the type of image shown. Based on the survey, we derive a speckle contrast threshold for which speckle can be seen, and separately we investigate a speckle disturbance limit that is tolerated by the majority of test persons.

The risk of tick-borne encephalitis virus (TBEV) introduction into Belgium remains high, and the presence of infected wildlife in Belgium is suspected. Domestic animals can serve as excellent sentinels for TBEV surveillance to install an early warning surveillance component for this emerging zoonotic disease of public health importance. In a targeted, risk-based and cross-sectional sampling design, serological screening was performed on Belgian cattle (n=650), selected from the 2010 Belgian national cattle surveillance serum bank. All samples were subjected to a gold standard TBEV seroneutralization test (SNT), based on the rapid fluorescent focus inhibition test (RFFIT) protocol. Seventeen bovines were seropositive (titer >1/15) and six had borderline results (1/10 < titer < 1/15). The accuracy of the RFFIT-SNT was confirmed in a mouse inoculation test. The overall bovine TBEV seroprevalence in the targeted area was estimated between 2.61% and 4.29%. This confirms for the first time the presence of infected foci in Belgium. Further surveillance in cattle, other sentinels, ticks, and humans at risk is recommended to further determine the location and size of endemic foci and the risk for public health.

Methicillin-resistant Staphylococcus aureus (MRSA) has long been recognized as an important pathogen in human medicine leading to hospital and community-acquired infections. However, it is now also considered a growing problem in veterinary medicine, although causing little or no disease. Although MRSA has already been detected in livestock including poultry, little is known about the epidemiology of MRSA in broiler and layer chickens. We therefore investigated 372 poultry farms in Belgium. We also compared the isolation method recommended by the European Food Safety Authority using two enrichment steps with an isolation method using only one enrichment step. Isolated MRSA was characterized by means of antimicrobial resistance profiling, spa typing, multi-locus sequence typing, and SCCmec typing. MRSA prevalence was 0.8% using the double broth enrichment method, while using the single broth enrichment method it was 1.8%. Five MRSA strains belonged to the livestock-associated (LA) MRSA ST398 (four with spa type t011 and one with t899), and three to the hospital-acquired MRSA ST239 spa type t037. The ST239 strains carried SCCmec type III while those belonging to ST398 carried SCCmec type IV or V. All isolates showed additional resistance to erythromycin and tetracycline apart from the expected resistance to cefoxitin and penicillin. All strains were susceptible to linezolid, mupirocin and vancomycin. In conclusion, a higher sensitivity for the isolation of LA-MRSA was obtained using only one enrichment step. While the typical LA-MRSA ST398 was present at low prevalence in poultry, human-associated strains have also been found.

In laser projection applications, laser light modules are often combined with rotating diffusers in order to reduce the appearance of speckle on the projection screen. The rotation of a diffuser in a laser beam generates a beam of partially coherent light. Propagation of this light through the different optical components constituting the laser projector is thus essential when investigating the appearance of speckle. In this paper, a computationally efficient simulation model is presented to propagate partially coherent light through a homogenizing rectangular light pipe. The light pipe alters the coherence properties of the light and different consequences are discussed. The outcomes of the simulation model are experimentally verified using a reversing wavefront Michelson interferometer.

The role of wild birds in the epidemiology and ecology of influenza A viruses has long been recognised (Alexander, 2007a). As a result of the emergence of a H5N1 highly pathogenic avian influenza (HPAI) virus and the apparent role of wild birds in its spread across Asia, Europe and Africa, avian influenza (AI) wild bird surveillance has been implemented in many countries including, since February 2006, a mandatory programme in the European Union (CEC, 2006a). In the present study the detection of virus excreted from Pekin ducks (Anas platyrhynchos) infected experimentally with A/mallard/England/2126/07 (H3N6) was investigated over a fourteen day period post-infection using cloacal and oropharyngeal swabs, with (wet) and without (dry) viral transport medium which were collected from each duck in alternating order. For influenza A virus matrix gene RNA detection, wet oropharyngeal swabs were significantly more sensitive than dry oropharyngeal on days 4-5 after infection. For cloacal samples, dry swabs were equivalent or superior to wet swabs throughout the study. Although differences in detection between dry and wet swabs were observed, the qualitative bird-level results were unaffected, meaning that the infection status of individual birds was correctly determined., (Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.)

We present a standardized procedure to measure the amount of speckle in laser based projection systems. The parameters of the measurement procedure are chosen such that the measured speckle contrast values are in correspondence with the subjective speckle perception of a human observer, independent of the particularities of the laser projector's illumination configuration. The resulting measurement configuration consists of a single digital image sensor in combination with a camera lens of which the settings are related to the human eye. In addition, a standardized measurement procedure and speckle pattern analysis method are suggested. Finally, the speckle measurement set-up is applied to a laser projection system and corresponding subjective speckle perception results of a large test public are discussed.

Tick-borne encephalitis virus (TBEV) is an important emerging tick-borne viral infection of humans and dogs in Europe. Currently, TBEV surveillance is virtually nonexistent in Belgium, which is considered nonendemic. A commercial enzyme-linked immunosorbent assay (ELISA) was adapted for the detection of TBEV-specific IgG-antibodies in canine sera. Serum samples of Belgian dogs were obtained from three diagnostic laboratories from Northern (n=688) and Southern Belgium (n=192). ELISA-positive and borderline samples were subjected to a TBEV rapid fluorescent focus inhibition confirmation test. One dog was confirmed TBEV seropositive. Several ELISA-positive and borderline sera underwent seroneutralization and hemagglutinin inhibition tests to rule out West Nile and Louping Ill viruses, but tested negative. The clinical history of the seropositive dog could not explain beyond doubt where and when TBEV infection was acquired. Further surveillance is necessary to determine whether this dog remains a single travel-related case or whether it represents an early warning of a possible future emergence of TBEV.

In this work we present a prototype multiview projection display that combines high-spatial and high-angular resolution with low complexity, compact form factor and potentially low-cost design. The system consists of a single projector and an image steering projection screen. It is based on beam steering using decentered microlens arrays in the projection screen and time-sequential rear-projection of the view images. The prototype has a 25 in. screen, a total of 27 viewing zones with XGA resolution and a horizontal field of view of 30°.