%0 Journal Article %J Avian Pathol %D 2017 %T Specific antibody-mediated immunity in the reproductive tract of laying chickens immunized against Newcastle disease with conventional attenuated and inactivated vaccines. %A Fabienne Rauw %A Nguyen, T G %A Ngabirano, E %A Sylvie Marché %A Bénédicte Lambrecht %X

Despite the widespread and successful use of Newcastle disease (ND) vaccines, Newcastle disease virus (NDV) can seriously injure the reproductive tract of egg-laying hens, leading to rapid egg-drop and poor shell quality. Few published studies investigated local NDV-specific immune response in the reproductive tract after ND vaccination of hens. The present study investigated, for the first time, local NDV-specific antibody-mediated immunity in segments of the oviduct during the laying period. Specific pathogen-free (SPF) White Leghorn chickens were immunized following an ND vaccination programme applied in the field, which combined ND-attenuated vaccine (inoculated subcutaneously at one day, 2 weeks and 11 weeks of age) with inactivated vaccine (inoculated intramuscularly at 17 weeks). The infundibulum, magnum, isthmus and uterus (segments of the reproductive tract) were harvested at 28 weeks and 32 weeks of age (during the laying period). Supernatant from ex vivo tissue culture was collected and tested by: (i) haemagglutination inhibition (HI) test, (ii) commercial IDVet ND-enzyme-linked immunosorbent assay (ELISA) and (iii) NDV-specific IgG, IgM and IgA in-house ELISAs. For all sampling time points and oviduct segments, all samples were positive for commercial ND-ELISA and in-house ELISA-IgG. However, six of these ELISA-IgG positive samples yielded negative results when submitted to the HI test. Interestingly, NDV-specific IgM and IgA were detected frequently in the infundibulum and magnum as compared to the isthmus and uterus. These results show that the antibody immune response in the oviduct was induced by the timing of attenuated and inactivated ND vaccinations.

%B Avian Pathol %V 46 %P 434-441 %8 2017 Aug %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/28290220?dopt=Abstract %R 10.1080/03079457.2017.1304528 %0 Journal Article %J Genome Announcements %D 2016 %T Complete Coding Sequences of One H9 and Three H7 Low-Pathogenic Influenza Viruses Circulating in Wild Birds in Belgium, 2009 to 2012 %A Steven Van Borm %A Rosseel, Toon %A Sylvie Marché %A Mieke Steensels %A Vangeluwe, Didier %A Linden, Annick %A Thierry van den Berg %A Bénédicte Lambrecht %B Genome Announcements %V 4 %8 Jun-06-2018 %G eng %N 3 %R 10.1128/genomeA.00540-16 %0 Journal Article %J Genome Announc %D 2016 %T Complete Coding Sequences of One H9 and Three H7 Low-Pathogenic Influenza Viruses Circulating in Wild Birds in Belgium, 2009 to 2012. %A Steven Van Borm %A Rosseel, Toon %A Sylvie Marché %A Mieke Steensels %A Vangeluwe, Didier %A Linden, Annick %A Thierry van den Berg %A Bénédicte Lambrecht %X

The complete coding sequences of four avian influenza A viruses (two H7N7, one H7N1, and one H9N2) circulating in wild waterfowl in Belgium from 2009 to 2012 were determined using Illumina sequencing. All viral genome segments represent viruses circulating in the Eurasian wild bird population.

%B Genome Announc %V 4 %8 2016 Jun 09 %G eng %N 3 %1 https://www.ncbi.nlm.nih.gov/pubmed/27284153?dopt=Abstract %R 10.1128/genomeA.00540-16 %0 Journal Article %J Veterinary Medicine and Science %D 2016 %T Evaluation of the kinetics of anti-NP and anti-HA antibody after infection of Pekin ducks with low pathogenic avian influenza virus %A Sylvie Marché %A Thierry van den Berg %A Bénédicte Lambrecht %K duck immune response %K HI test %K notifiable avian influenza %K NP ELISA %K Pekin duck %K serological diagnosis %X

Serological monitoring is a feature of surveillance programmes for the detection of the circulation of notifiable low pathogenic avian influenza (LPAI) viruses in commercial poultry holdings. Commercial multispecies nucleoprotein (NP) enzyme-linked immunosorbent assays (ELISAs) have been replacing the haemagglutination inhibition (HI) test as pre-screening tools. Few comparative studies have been conducted to test sera from domestic ducks for diagnostic purposes. Therefore, we evaluated the correlation between commercial NP ELISAs and the HI test. Anti-NP and anti-haemagglutinin (HA) antibodies were measured in sera from domestic ducks that had undergone serological screening and from juvenile domestic Pekin ducks that were experimentally infected with LPAI viruses. The findings highlight an absence of a correlation between NP ELISA and HI results with both field and experimental duck sera. Dissimilar kinetics of the antibodies detected during the follow-up evaluation of the humoral immune responses in experimentally infected ducks may explain this lack of correlation. Indeed, anti-NP titres decreased over time, whereas anti-HA titres remained unchanged after inoculation with the H3N1 LPAI virus isolated from domestic duck or the H7N1 LPAI virus isolated from chicken. Despite these differences, the NP ELISA may serve as a valid pre-screening tool to detect circulating LPAI viruses in domestic duck populations at the flock level.

%B Veterinary Medicine and Science %V 2 %8 2016 %G eng %N 1 %& 36 %R 10.1002/vms3.18 %0 Journal Article %J Infect Ecol Epidemiol %D 2016 %T First TBEV serological screening in Flemish wild boar. %A Sophie Roelandt %A Vanessa Suin %A Yves Van der Stede %A Lamoral, Sophie %A Sylvie Marché %A Marylène Tignon %A Saiz, Juan Carlos %A Escribano-Romero, Estela %A Casaer, Jim %A Bernard Brochier %A Steven Van Gucht %A S. Roels %A Vervaeke, Muriel %X

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.

%B Infect Ecol Epidemiol %V 6 %P 31099 %8 2016 %G eng %1 http://www.ncbi.nlm.nih.gov/pubmed/27087689?dopt=Abstract %R 10.3402/iee.v6.31099 %0 Journal Article %J Avian Dis %D 2016 %T Impact of Age, Season, and Flowing vs. Stagnant Water Habitat on Avian Influenza Prevalence in Mute Swan (Cygnus olor) in Belgium. %A Bénédicte Lambrecht %A Sylvie Marché %A Houdart, P %A Thierry van den Berg %A Vangeluwe, D %K Animals %K Anseriformes %K Antibodies, Viral %K Belgium %K Ecosystem %K Female %K Influenza A Virus, H5N1 Subtype %K Influenza in Birds %K Male %K prevalence %K Seasons %K Seroepidemiologic Studies %K virulence %X

Due to their probable role in the spread of Asian highly pathogenic avian influenza (HPAI) H5N1 virus, and in order to explore its implication in the low pathogenic avian influenza (LPAI) virus epidemiology, mute swans represent one particular wild bird species specifically targeted in the avian influenza (AI) surveillance elaborated in Belgium. A total of 640 individual mute swans have been sampled during a 4-yr AI surveillance program (2007-2010) to determine the AI seroprevalence and viroprevalence in this species; all were analyzed through age, temporal, and habitat (flowing and stagnant water) factors. Using a nucleoprotein (NP)-based ELISA, a global antibody prevalence of 35% has been found and was characterized by two peaks in the winter and the summer that might be indicative of a greater LPAI virus circulation in the autumn than in the spring. A significantly higher antibody prevalence was detected in adult swans (53.8%) as compared to juveniles (15.5%). In contrast, a low prevalence of infection (2.7%) was found, mainly in juvenile mute swans and only during the autumn migration period. Interestingly, an impact of water habitat was observed based on the comparison of the antibody prevalence and prevalence of infection from swan populations living on stagnant water vs. flowing water, suggesting that stagnant water provides a more-favorable environment for LPAI persistence and transmission.

%B Avian Dis %V 60 %P 322-8 %8 2016 May %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/27309074?dopt=Abstract %R 10.1637/11132-050815-Reg %0 Journal Article %J Avian Dis %D 2016 %T Multiyear Serological Surveillance of Notifiable Influenza A Viruses in Belgian Poultry: A Retrospective Analysis. %A Sylvie Marché %A Houdart, Philippe %A Thierry van den Berg %A Bénédicte Lambrecht %K Animals %K Antibodies, Viral %K Belgium %K Chickens %K Ducks %K Enzyme-Linked Immunosorbent Assay %K Geese %K Influenza A virus %K Influenza in Birds %K Poultry Diseases %K Retrospective Studies %K Seroepidemiologic Studies %K Turkeys %X

Surveillance of notifiable avian influenza (NAI) virus is mandatory in European member states, and each year a serological survey is performed to detect H5 and H7 circulation in poultry holdings. In Belgium, this serological monitoring is a combination of a stratified and a risk-based approach and is applied to commercial holdings with more than 200 birds. Moreover, a competitive nucleoprotein (NP) ELISA has been used as first screening method since 2010. A retrospective analysis of the serological monitoring performed from 2007 through 2013 showed sporadic circulation of notifiable low-pathogenicity avian influenza (LPAI) viruses in Belgian holdings with a fluctuating apparent flock seroprevalence according to years and species. Overall, the highest apparent flock seroprevalence was detected for the H5 subtype in domestic Anatidae, with 20%-50% for breeding geese and 4%-9% for fattening ducks. Positive serology against non-H5/H7 viruses was also observed in the same species with the use of the IDScreen influenza A antibody competition ELISA kit (ID-vet NP ELISA), and confirmed by isolation of H2, H3, H6, and H9 LPAI viruses. Among Galliformes, the apparent flock seroprevalence was lower, ranging between 0.3% and 1.3%. Circulation of notifiable LPAI viruses was only observed in laying hens with a similar seroprevalence for H5 and H7. Based on ID-vet NP ELISA results, no circulation of LPAI viruses, regardless the subtype, was observed in breeding chickens and fattening turkeys. Retrospectively, the use of an ELISA as first-line test not only reduced the number of hemagglutination inhibition tests to be performed, but also gave a broader evaluation of the prevalence of LPAI viruses in general, and might help to identify the most at-risk farms.

%B Avian Dis %V 60 %P 409 %8 2016 May %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/27309088?dopt=Abstract %R 10.1637/0005-2086-60.01s1.409 %0 Journal Article %J Avian Dis %D 2016 %T Protection Afforded by a Recombinant Turkey Herpesvirus-H5 Vaccine Against the 2014 European Highly Pathogenic H5N8 Avian Influenza Strain. %A Mieke Steensels %A Fabienne Rauw %A Thierry van den Berg %A Sylvie Marché %A Gardin, Y %A Palya, V %A Bénédicte Lambrecht %K Animals %K Chickens %K Europe %K Galliformes %K Genetic Vectors %K Herpesvirus 1, Meleagrid %K Influenza A Virus, H5N1 Subtype %K Influenza A Virus, H5N8 Subtype %K Influenza in Birds %K Influenza Vaccines %K Vaccination %K Vaccines, Synthetic %X

A highly pathogenic avian influenza (HPAI) H5N8 (clade 2.3.4.4) virus, circulating in Asia (South Korea, Japan, and southern China) since the beginning of 2014, reached the European continent in November 2014. Germany, the Netherlands, the United Kingdom, Italy, and Hungary confirmed H5N8 infection of poultry farms of different species and of several wild bird species. Unlike the Asian highly pathogenic (HP) H5N1, this HP H5N8 also went transatlantic and reached the American West Coast by the end of 2014, affecting wild birds as well as backyard and commercial poultry. This strain induces high mortality and morbidity in Galliformes, whereas wild birds seem only moderately affected. A recombinant turkey herpesvirus (rHVT) vector vaccine expressing the H5 gene of a clade 2.2 H5N1 strain (rHVT-H5) previously demonstrated a highly efficient clinical protection and reduced viral excretion against challenge with Asian HP H5N1 strains of various clades (2.2, 2.2.1, 2.2.1.1, 2.1.3, 2.1.3.2, and 2.3.2.1) and was made commercially available in various countries where the disease is endemic. To evaluate the protective efficacy of the rHVT-H5 vaccine against the first German H5N8 turkey isolate (H5N8 GE), a challenge experiment was set up in specific-pathogen-free (SPF) chickens, and the clinical and excretional protection was evaluated. SPF chickens were vaccinated subcutaneously at 1 day old and challenged oculonasally at 4 wk of age with two viral dosages, 10(5) and 10(6) 50% egg infective doses. Morbidity and mortality were monitored daily in unvaccinated and vaccinated groups, whereas viral shedding by oropharyngeal and cloacal routes was evaluated at 2, 5, 9, and 14 days postinoculation (dpi). Serologic monitoring after vaccination and challenge was also carried out. Despite its high antigenic divergence of the challenge H5N8 strain, a single rHVT-H5 vaccine administration at 1 day old resulted in a full clinical protection against challenge and a significant reduction of viral shedding in the vaccinated birds.

%B Avian Dis %V 60 %P 202-9 %8 2016 May %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/27309056?dopt=Abstract %R 10.1637/11126-050615-Reg.1 %0 Journal Article %J Epidemiol Infect %D 2015 %T Extended transmission of two H5/H7 low pathogenic avian influenza viruses in chickens. %A Claes, G %A Bénédicte Lambrecht %A Dewulf, J %A Thierry van den Berg %A Sylvie Marché %K Animals %K Chickens %K Influenza A Virus, H5N2 Subtype %K Influenza A Virus, H7N1 Subtype %K Influenza in Birds %K Virus Shedding %X

Transmission experiments are useful for investigating the mechanisms of low pathogenic notifiable avian influenza virus (LPNAI) transmission. In this study, the hypothesis that inoculation-infected chickens are more infectious than contact-infected chickens was tested. To this end, extended transmission experiments with one H5N2 and one H7N1 LPAIV which had previously been characterized in a series of standard transmission experiments were conducted in specific pathogen-free (SPF) chickens. For the H5N2 LPAIV, the infectivity of contact-infected chickens was similar to the infectivity of inoculated chickens. Despite results from a previous study suggesting the H7N1 LPAIV strain to be similarly infectious to SPF chickens as the H5N2 LPAIV strain, the acquisition of contact-infected chickens proved more difficult for H7N1 LPAIV. It was assumed that this might have been a consequence of the length and timing of the exposure period. In conclusion, for LPNAIVs that first seemed equally infectious, short-term transmissibility may vary considerably.

%B Epidemiol Infect %V 143 %P 781-90 %8 2015 Mar %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/24924291?dopt=Abstract %R 10.1017/S0950268814001307 %0 Journal Article %J Transbound Emerg Dis %D 2014 %T Chasing notifiable avian influenza in domestic poultry: a case report of low-pathogenic avian influenza h5 viruses in two Belgian holdings. %A Sylvie Marché %A Steven Van Borm %A Bénédicte Lambrecht %A Houdart, P %A Thierry van den Berg %K Animals %K Belgium %K Birds %K Disease Outbreaks %K Enzyme-Linked Immunosorbent Assay %K Hemagglutination Tests %K Influenza A Virus, H5N2 Subtype %K Influenza in Birds %K Poultry Diseases %X

In December 2008, bird species in two geographically distant holdings were found positive for H5 viruses following the annual Avian influenza serological screening in Belgium. The virological tests performed identified in one holding a low-pathogenic avian influenza (LPAI) virus subtype H5N2, and a H5 LPAI virus was identified by real-time PCR and direct sequencing at the second holding. The first farm was an outdoor mixed holding housing ornamental birds and poultry (n = 6000) and the second a free-range geese breeding farm (n = 1500). No clinical signs or mortalities were reported. Control measures defined by Council Directive 2005/94/EC were followed, including notification to the European Commission via the Animal Disease Notification System and to the World Organization for Animal Health, and poultry were killed, while ornamental bird species were quarantined. Partial sequencing of the H5N2 virus haemagglutinin and neuraminidase N2 gene sequences revealed a close homology to some recent LPAI isolates identified from wild birds in Germany and Italy and from wild birds in Eurasia and Africa, respectively. It is noteworthy that, these two holdings were already H5 positive based on HI test results carried out during the previous serological screening; however, no virus was detected at that time. To have a better understanding of the potential 'silent' circulation of the H5N2 isolate in the field, experimental infections of chickens and turkeys were performed. The low excretion detected might in part explain viral persistence not associated with spread between gallinaceous birds in the same holding, indicating that the H5N2 LPAI isolate was not fully adapted to these two poultry species. Our results highlighted limitations to only using serological screening for the early detection of LPAI in an 'at-risk farm', suggesting that virological and serological monitoring tests be applied simultaneously as a means of testing animals in 'at-risk farms'.

%B Transbound Emerg Dis %V 61 %P 526-36 %8 2014 Dec %G eng %N 6 %1 https://www.ncbi.nlm.nih.gov/pubmed/23347839?dopt=Abstract %R 10.1111/tbed.12056 %0 Journal Article %J Epidemiol Infect %D 2014 %T An experimental model to analyse the risk of introduction of a duck-originated H5 low-pathogenic avian influenza virus in poultry through close contact and contaminative transmission. %A Claes, G %A Sylvie Marché %A Dewulf, J %A Thierry van den Berg %A Bénédicte Lambrecht %K Animals %K Chickens %K Drinking Water %K Ducks %K Housing, Animal %K Influenza A virus %K Influenza in Birds %K Models, Biological %K Risk Factors %K RNA, Viral %K Specific Pathogen-Free Organisms %X

Aquatic wild birds are often carriers of low-pathogenic avian influenza viruses (LPAIVs). If H5 and H7 LPAIVs are transmitted to poultry and have the opportunity to circulate, a highly pathogenic AIV may arise. Contact with aquatic wild birds is one of the most important ways in which these LPAIVs can be introduced into poultry flocks. In this study, the transmissibility of a duck-originated H5 LPAIV between ducks and chickens was analysed in a series of animal experiments, using different transmission routes. Results indicate that the outcome of virus intake by chickens exposed to infectious ducks depends on the way the virus is presented. Faecally contaminated drinking water proved to be the most efficient route by which the virus can be transmitted to chickens. The results from this study also suggest that some duck-originated H5 LPAIVs may be introduced to poultry but do not have the potential to become established in poultry populations.

%B Epidemiol Infect %V 142 %P 1836-47 %8 2014 Sep %G eng %N 9 %1 http://www.ncbi.nlm.nih.gov/pubmed/24252718?dopt=Abstract %R 10.1017/S0950268813002793 %0 Journal Article %J Avian Dis %D 2012 %T Different replication profiles in specific-pathogen-free chickens of two H7 low pathogenic avian influenza viruses isolated from wild birds. %A Sylvie Marché %A Claes, Gerwin %A Steven Van Borm %A Vangeluwe, Didier %A Thierry van den Berg %A Bénédicte Lambrecht %K Animals %K Animals, Wild %K Anseriformes %K Chickens %K Hemagglutinin Glycoproteins, Influenza Virus %K Influenza A virus %K Influenza in Birds %K Phylogeny %K Specific Pathogen-Free Organisms %K Time Factors %K Virus Replication %X

During an active wild bird survey conducted in Belgium from 2007 to 2011, two low pathogenic avian influenza (LPAI) H7 viruses were isolated from wild birds: an H7N1 virus from a common shelduck (Tadorna tadorna) and an H7N7 virus from a Canada goose (Branta canadensis). The H7 sequence analyses and intravenous pathogenicity indices indicated that they were both low pathogenic isolates and genetically related to other recent European H7 LPAIs isolated from wild birds. Interestingly, the two isolates showed different replication profiles in specific-pathogen-free (SPF) chickens, but poultry can be at risk from both. Indeed, the H7N1 isolated from the common shelduck had the ability to infect and to replicate efficiently in SPF chickens as indicated by high oropharyngeal and cloacal excretions compatible with efficient transmission as well as strong immune responses. On the other hand, the H7N7 isolated from the Canada goose presented a lower replication profile because the inoculated chickens excreted less virus, mostly via the oropharyngeal route, and only three chickens seroconverted. None of the chickens showed clinical signs during the entire infection. Our study using an SPF chicken model underlines that the mechanisms of adaptation of LPAIs in poultry remain unpredictable and are still poorly understood but it represents a powerful tool to gain a better evaluation of the risks of LPAI circulation in poultry.

%B Avian Dis %V 56 %P 959-65 %8 2012 Dec %G eng %N 4 Suppl %1 https://www.ncbi.nlm.nih.gov/pubmed/23402119?dopt=Abstract %R 10.1637/10155-040912-ResNote.1 %0 Journal Article %J Avian Dis %D 2012 %T Evaluation of four enzyme-linked immunosorbent assays for the serologic survey of avian influenza in wild bird species. %A Claes, Gerwin %A Vangeluwe, Didier %A Yves Van der Stede %A Thierry van den Berg %A Bénédicte Lambrecht %A Sylvie Marché %K Animals %K Animals, Wild %K Birds %K Enzyme-Linked Immunosorbent Assay %K Influenza in Birds %K Seroepidemiologic Studies %K Serologic Tests %X

Wild birds that reside in aquatic environments are the major reservoir of avian influenza viruses (AIVs). Since this reservoir of AIVs forms a constant threat for poultry, many countries have engaged in AIV surveillance. More and more commercial enzyme-linked immunosorbent assays (ELISA) are available for serologic surveillance, but these tests are often developed and validated for use in domestic poultry. However, for a correct interpretation of ELISA test results from wild bird sera, more information is needed. In the present study, four ELISA test kits (ID-Vet IDScreen, IDEXX FlockChek AI MultiS-Screen Ab Test Kit, Synbiotics FluDETECTBE, and BioChek AIMSp) were compared for the serologic analysis of 172 serum samples from mallard, mute swan, and Canada goose. Samples were selected based on ID-Vet IDScreen results to obtain an approximately equal number of positive and negative samples. In addition, 92 serum samples from experimentally infected specific-pathogen-free (SPF) chickens and Pekin ducks were included in the tests for validation purposes. Cohen's kappa statistics and Spearman correlation coefficients were calculated for each combination of two tests and for each bird species. Test agreement for mallard sera varied from poor to moderate, while test results for Canada goose and swan sera agreed from fair to almost perfect. The best agreement was obtained with sera from experimentally infected SPF chickens and Pekin ducks. This study shows that some care must be taken before using nucleoprotein ELISAs for the testing of sera from wild birds and that more reliable validation studies should be considered before their use in the serologic surveillance of wild birds.

%B Avian Dis %V 56 %P 949-54 %8 2012 Dec %G eng %N 4 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/23402117?dopt=Abstract %R 10.1637/10165-040912-Reg.1 %0 Journal Article %J Avian Dis %D 2010 %T Evaluation of different serologic markers for the early detection of avian influenza infection in chickens. %A Sylvie Marché %A Bénédicte Lambrecht %A Thierry van den Berg %K Animals %K Biomarkers %K Chickens %K Influenza A virus %K Influenza in Birds %K Specific Pathogen-Free Organisms %X

Viruses of all subtypes may be introduced into domestic poultry, but only H5 and H7 low pathogenicity avian influenza viruses can mutate during circulation in poultry and emerge as high pathogenicity avian influenza variants. It is therefore essential to monitor the field situation continuously to detect low pathogenicity notifiable avian influenza (LPNAI) as soon as possible. With the emergence of the highly pathogenic H5N1, markers of infection of avian influenza are becoming more and more significant. They are important as early warning systems, and they can also be valuable tools as companion tests of vaccines (differentiating infected from vaccinated animals), but they might also be informative about the evaluation of the degree of adaptation and the timing of infection. Therefore, several experimental infections of specific-pathogen-free chickens were conducted to follow the kinetics of antibody responses against the hemagglutinin, the neuraminidase, the nucleoprotein, and the M2e after infections with LPNAI viruses isolated from waterfowl or already adapted to chicken. Overall, the immune responses against the different antigens showed similar kinetics in the different infected animals, but they were lower when the animals were infected with AI viruses originating from waterfowl, and the kinetics of the M2e antibodies was quite different. Indeed, it was rather shorter and disappeared more rapidly (approximately 35 days postinfection) compared to the kinetics of the other antibodies. Therefore, the detection of the antibodies against M2e peptide could be an interesting tool to detect recent infection, and these preliminary results indicated that the production of M2e antibodies might be correlated with the degree of adaptation of LPNAIs.

%B Avian Dis %V 54 %P 690-8 %8 2010 Mar %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/20521717?dopt=Abstract %R 10.1637/8907-043009-ResNote.1 %0 Journal Article %J Avian Dis %D 2010 %T Evaluation of different strategies for the use of ELISA tests as first screening tools for serologic surveillance of low pathogenic avian influenza in the Belgian poultry sector. %A Sylvie Marché %A Thierry van den Berg %K Animals %K Belgium %K Enzyme-Linked Immunosorbent Assay %K Influenza A virus %K Influenza in Birds %K Poultry %K Reagent Kits, Diagnostic %K Sensitivity and Specificity %K Seroepidemiologic Studies %X

Since the emergence of the highly pathogenic avian influenza H5N1, avian influenza surveillance has been expanded in Europe. The serologic monitoring of domestic poultry is usually accomplished using the reference hemagglutination inhibition (HI) test for the detection of H5 and H7 subtypes. However, as the number of tested sera has been increasing, there is a need for another serologic method that could be used as a preliminary screening test. A comparison of four enzyme-linked immunosorbent assay (ELISA) tests (two indirect and two competitive) was conducted, and they showed good specificity and higher sensitivity than the HI test. The selected ELISA tests were then tested using approximately 800 field sera representative of different poultry species, and a simulation was done to determine the best strategy for screening. The first strategy was testing both gallinaceous and nongallinaceous sera with a competitive ELISA and using the HI test for H5 and H7 as a confirmatory test. The second strategy was testing only gallinaceous bird sera with the indirect ELISA with confirmatory H5 and H7 HI and all nongallinaceous sera by the H5 and H7 HI test. In the Belgian poultry context, the best strategy seems to be the use of a blocking ELISA as the primary screening tool to test all the poultry sera, followed by confirmation by H5 and H7 HI test subtyping.

%B Avian Dis %V 54 %P 627-31 %8 2010 Mar %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/20521705?dopt=Abstract %R 10.1637/8759-033109-Reg.1 %0 Journal Article %J Avian Dis %D 2010 %T Evaluation of rapid antigen detection kits for the diagnosis of highly pathogenic avian influenza H5N1 infection. %A Sylvie Marché %A Thierry van den Berg %K Animals %K Chickens %K Influenza A Virus, H5N1 Subtype %K Influenza in Birds %K Reagent Kits, Diagnostic %K Sensitivity and Specificity %K Specific Pathogen-Free Organisms %X

Early detection of highly pathogenic (HP) strains of avian influenza, especially the HP H5N1, is important in terms of controlling and minimizing the spread of the virus. Several rapid antigen detection kits that are able to detect influenza A viruses in less than 1 hr are commercially available, but only a few of them have been evaluated. In this study, four commercially available rapid tests for veterinary usage and two tests for human usage were evaluated and compared. The evaluation of the detection limits of the different tests established with serial dilution of HP H5N1 indicated that most of them have a detection limit of about 10(5) to 10(6) 50% tissue culture infectious dose/ml. None of the tests was able to detect virus in oral and cloacal swabs 24 hr post-experimental infection of specific-pathogen-free chickens with HP H5N1. However, 48 hr postinfection, almost all of the rapid tests were able to detect infected birds (dead or alive). Moreover, organs were also successful samples for detection of H5N1 with the rapid tests. Unexpectedly, the specificity was not very high for some tests. However, in general in this study, the tests for veterinary usage showed better sensitivity. To conclude, these tests offer good indicative value in the event of an outbreak, but as a result of their low sensitivity and some aspecific reactions, test results always need to be confirmed by other methods.

%B Avian Dis %V 54 %P 650-4 %8 2010 Mar %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/20521709?dopt=Abstract %R 10.1637/8779-040109-ResNote.1 %0 Journal Article %J Avian Dis %D 2010 %T H5N1 high pathogenicity avian influenza virus survival in different types of water. %A Domańska-Blicharz, Katarzyna %A Minta, Zenon %A Smietanka, Krzysztof %A Sylvie Marché %A Thierry van den Berg %K Animals %K Animals, Wild %K Birds %K Disease Outbreaks %K Influenza A Virus, H5N1 Subtype %K Influenza in Birds %K Poland %K WATER %K Water Microbiology %X

Persistence of H5N1 high pathogenicity avian influenza virus (HPAIV), isolated during the epidemic in wild birds in Poland in 2006, was evaluated in three water samples derived from the sources known to host wild water birds (city pond, Vistula river mouth, and Baltic Sea). The virus was tested at two concentrations (10(4) and 10(6) median tissue culture infective dose per milliliter) and at three temperatures (4 C, 10 C, and 20 C), representing average seasonal temperatures in Poland. All tested water samples were filtered before virus inoculation, and one unfiltered sample (Baltic seawater) was also tested. Infectivity was determined twice a week over a 60-day trial period by microtiter endpoint titration. The persistence of the virus varied considerably depending on its concentration and also on physico-chemical parameters of the water, such as temperature and salinity. Avian influenza virus survival was the highest at 4 C and the lowest at 20 C. Prolonged infectivity of the virus in Baltic seawater (brackish, 7.8 ppt) was also seen. In distilled water, the virus retained its infectivity beyond the 60-day study period. Interestingly, a devastating effect of the unfiltered fraction of seawater was seen as the virus disappeared in this fraction the quickest in all studied combinations; thus, biologic factors may also affect infectivity of HPAIV.

%B Avian Dis %V 54 %P 734-7 %8 2010 Mar %G eng %N 1 Suppl %1 http://www.ncbi.nlm.nih.gov/pubmed/20521724?dopt=Abstract %R 10.1637/8786-040109-ResNote.1 %0 Journal Article %J Avian Dis %D 2010 %T Rapid detection of Eurasian and American H7 subtype influenza A viruses using a single TaqManMGB real-time RT-PCR. %A Steven Van Borm %A Suarez, David L %A Boschmans, Marc %A Orkun Ozhelvaci %A Sylvie Marché %A Thierry van den Berg %K Americas %K Animals %K Asia %K Chickens %K Cloaca %K Europe %K Hemagglutinin Glycoproteins, Influenza Virus %K Influenza A virus %K Influenza in Birds %K Oropharynx %K Reverse Transcriptase Polymerase Chain Reaction %K Specific Pathogen-Free Organisms %X

A real-time reverse transcription PCR (RRT-PCR) targeting a highly conserved HA2 H7 region was developed for the detection of all H7 subtype avian influenza viruses (PanH7). The wide phylogenetic scope and analytical sensitivity and specificity were validated with the use of a panel of 56 diverse influenza A viruses. The detection limit was determined with the use of serial dilutions of Eurasian isolates A/Ck/BE/06775/2003 and A/Ck/It/1067/v99 and North American isolates A/CK/PA/ 143586/2001 and A/Quail/PA/20304/1998, to be 1 log10 higher than the detection limit of the generic influenza A matrix RRT-PCR (about 2.5 EID50/reaction compared to 0.25 EID50/reaction for matrix). Diagnostic test properties of PanH7 were determined with the use of 102 swabs from A/Ck/It/1067/v99 experimentally infected chickens, and were not affected by the increased detection limit of PanH7. In comparison to matrix RRT-PCR and virus isolation in embryonated chicken eggs (VI), the PanH7 detected more weakly positive oropharyngeal swabs at the onset of the infection. PanH7 diagnostic sensitivity compared to virus isolation (VI) was 83.3% (compared to 72.2% for matrix RRT-PCR); and diagnostic specificity was 88.1% (94.0% for matrix). The PanH7 test can also be tailored to detect only American (AmH7) or only Eurasian (EurH7) strains by changing the mix of forward and reverse primers used in combination with the unique probe. Overall, this new test is a valuable tool for the detection and identification of H7 subtype influenza A.

%B Avian Dis %V 54 %P 632-8 %8 2010 Mar %G eng %N 1 Suppl %1 https://www.ncbi.nlm.nih.gov/pubmed/20521706?dopt=Abstract %R 10.1637/8734-032509-ResNote.1 %0 Journal Article %J Avian Dis %D 2010 %T Redesigning the serological surveillance program for notifiable avian influenza in Belgian professional poultry holdings. %A Sarah Welby %A Thierry van den Berg %A Sylvie Marché %A Houdart, Philippe %A Hooyberghs, Jozef %A Mintiens, Koen %K Agriculture %K Animals %K Belgium %K Communicable Disease Control %K Disease Notification %K Influenza in Birds %K National Health Programs %K Poultry %K Seroepidemiologic Studies %X

This study was aimed at redesigning the Belgian active surveillance program for domestic birds in professional poultry holdings based on a risk analysis approach. A stochastic quantitative analysis, combining all data sources, was run to obtain sensitivity estimates for the detection of an infected bird in the different risk groups identified. An optimal number of holdings for each risk group was then estimated on the basis of the different sensitivities obtained. This study proved to be a useful tool for decision makers, providing insight on how to reallocate the total amount of samples to be taken in the coming year(s) in Belgium, thus optimizing the field resources and improving efficiency of disease surveillance such as required by the international standards.

%B Avian Dis %V 54 %P 597-605 %8 2010 Mar %G eng %N 1 Suppl %1 https://www.ncbi.nlm.nih.gov/pubmed/20521701?dopt=Abstract %R 10.1637/8749-033009-Reg.1 %0 Journal Article %J Comparative Immunology, Microbiology and Infectious Diseases %D 2008 %T Influenza vaccines and vaccination strategies in birds %A Thierry van den Berg %A Bénédicte Lambrecht %A Sylvie Marché %A Mieke Steensels %A Steven Van Borm %A Bublot, Michel %B Comparative Immunology, Microbiology and Infectious Diseases %V 31 %8 Jan-03-2008 %G eng %N 2-3 %R 10.1016/j.cimid.2007.07.004 %0 Journal Article %J Comp Immunol Microbiol Infect Dis %D 2008 %T Influenza vaccines and vaccination strategies in birds. %A Thierry van den Berg %A Bénédicte Lambrecht %A Sylvie Marché %A Mieke Steensels %A Steven Van Borm %A Bublot, Michel %K Animals %K Birds %K Horses %K Humans %K Influenza A Virus, H5N1 Subtype %K Influenza in Birds %K Influenza Vaccines %K Influenza, Human %K Orthomyxoviridae Infections %K Swine %X

Although it is well accepted that the present Asian H5N1 panzootic is predominantly an animal health problem, the human health implications and the risk of human pandemic have highlighted the need for more information and collaboration in the field of veterinary and human health. H5 and H7 avian influenza (AI) viruses have the unique property of becoming highly pathogenic (HPAI) during circulation in poultry. Therefore, the final objective of poultry vaccination against AI must be eradication of the virus and the disease. Actually, important differences exist in the control of avian and human influenza viruses. Firstly, unlike human vaccines that must be adapted to the circulating strain to provide adequate protection, avian influenza vaccination provides broader protection against HPAI viruses. Secondly, although clinical protection is the primary goal of human vaccines, poultry vaccination must also stop transmission to achieve efficient control of the disease. This paper addresses these differences by reviewing the current and future influenza vaccines and vaccination strategies in birds.

%B Comp Immunol Microbiol Infect Dis %V 31 %P 121-65 %8 2008 Mar %G eng %N 2-3 %1 https://www.ncbi.nlm.nih.gov/pubmed/17889937?dopt=Abstract %R 10.1016/j.cimid.2007.07.004 %0 Journal Article %J Infect.Immun. %D 2006 %T Members of the 30- to 32-kilodalton mycolyl transferase family (Ag85) from culture filtrate of Mycobacterium avium subsp. paratuberculosis are immunodominant Th1-type antigens recognized early upon infection in mice and cattle16 %A Rosseels,V. %A Sylvie Marché %A Virginie Roupie %A M. Govaerts %A Godfroid,J. %A Walravens,K. %A K Huygen %K 0 %K a %K acid %K Acids %K Acyltransferases %K Amino acids %K an %K Animals %K Antigens %K Antigens,Bacterial %K article %K AS %K BCG %K Belgium %K biosynthesis %K blood %K Born %K Brussels %K Cattle %K Cell %K Cell Proliferation %K cells %K Cells,Cultured %K Components %K culture %K Development %K effective %K Epitopes %K families %K Family %K growth & development %K im %K Immunodominant Epitopes %K immunology %K INFECTION %K Institute %K Interferon-gamma %K IS %K journal %K Laboratories %K Lymphocyte Activation %K M %K Male %K MEDIA %K metabolism %K mice %K Mice,Inbred C57BL %K Mice,Mutant Strains %K microbiology %K Molecular Weight %K Mycobacterium %K Mycobacterium avium subsp.paratuberculosis %K Mycobacterium bovis %K Mycobacterium tuberculosis %K ON %K Paratuberculosis %K pathology %K Peptides %K present %K Print %K protein %K recombinant %K Research %K Research Support %K response %K Responses %K result %K results %K SB - IM %K secretion %K Spleen %K Synthetic %K Th1 Cells %K Tuberculosis %K vaccine %K young %X The characterization of protective antigens is essential for the development of an effective, subunit-based vaccine against paratuberculosis. Surface-exposed and secreted antigens, present abundantly in mycobacterial culture filtrate (CF), are among the well-known protective antigens of Mycobacterium tuberculosis and Mycobacterium bovis. Culture filtrate, prepared from Mycobacterium avium subsp. paratuberculosis ATCC 19698 grown as a surface pellicle on synthetic Sauton medium, was strongly and early recognized in experimentally infected B6 bg/bg beige mice and cattle, as indicated by elevated spleen cell gamma interferon (IFN-gamma) secretion and lymphoproliferative responses of peripheral blood mononuclear cells, respectively. Strong proliferative and ex vivo IFN-gamma responses against antigen 85 (Ag85) complex (a major protein component from M. bovis BCG culture filtrate) could be detected in cattle as early as 10 weeks after oral M. avium subsp. paratuberculosis infection. Synthetic peptides from the Ag85A and Ag85B components of this complex were strongly recognized, whereas T-cell responses were weaker against peptides from the Ag85C protein. A promiscuous T-cell epitope spanning amino acids 145 to 162 of Ag85B (identical sequence in M. bovis and M. avium subsp. paratuberculosis) was identified in experimentally infected cattle. Finally, young calves, born from cows with confirmed paratuberculosis, demonstrated proliferative responses to purified, recombinant Ag85A and Ag85B from M. avium subsp. paratuberculosis. These results indicate that the M. avium subsp. paratuberculosis Ag85 homologues are immunodominant T-cell antigens that are recognized early in experimental and natural infection of cattle %B Infect.Immun. %V 74 %P 202 - 212 %8 0/1/2006 %G eng %N 1 %1 38341 %& 202 %R 74/1/202 [pii];10.1128/IAI.74.1.202-212.2006 [doi] %0 Journal Article %J Vet.Immunol.Immunopathol. %D 2002 %T IFN-gamma diagnostic tests in the context of bovine mycobacterial infections in Belgium37 %A Walravens,K. %A Sylvie Marché %A Rosseels,V. %A Wellemans,V. %A Boelaert,F. %A K Huygen %A Godfroid,J. %K a %K analysi %K analysis %K Animal %K Animals %K Antigens %K article %K AS %K at %K Belgium %K blood %K Brussels %K Cattle %K classification %K Context %K Countries %K criteria %K Diagnosis %K duration %K Enzyme-Linked Immunosorbent Assay %K Evolution %K im %K immune response %K immunology %K INFECTION %K infections %K Interferon-gamma %K IS %K journal %K M %K Mycobacterium %K Mycobacterium bovis %K Mycobacterium phlei %K ON %K Paratuberculosis %K present %K Print %K Ratio %K repeated %K Research %K response %K Responses %K SB - IM %K Short %K specific %K status %K Strategies %K Strategy %K study %K Test %K TESTING %K tests %K Tuberculosis %K Tuberculosis,Bovine %K US %K veterinary %X In countries where cattle tuberculosis caused by Mycobacterium bovis (Mbov) and paratuberculosis caused by Mycobacterium avium subsp. paratuberculosis (Mptb) are present, testing strategies for the Mbov eradication have to discriminate between these two infections. Present indirect tests are based on the analysis of the specific cellular immune response (DTH, IFN-gamma) against crude mycobacterial antigens (avian and bovine PPD). In this study, we compared the evolution of the IFN-gamma responses of animals experimentally infected with Mbov, Mptb, or inoculated with Mycobacterium phlei. Mbov inoculation induced a strong IFN-gamma response that allows rapid classification of the status of the animals following interpretation criteria set up by us. Experimental inoculation with M. phlei induced sensitisation to mycobacterial antigens as detected by the IFN-gamma test but these reactions were of short duration, therefore, repeated testing allows us to define these animals as aspecific reactors. IFN-gamma response induced after oral inoculation of calves with Mptb was of low intensity and ratio of responses measured against avian versus bovine PPD did not allow a clear diagnostic at least for the six first month of infection %B Vet.Immunol.Immunopathol. %V 87 %P 401 - 406 %8 10/9/2002 %G eng %N 3-4 %1 39232 %& 401 %R S0165242702000922 [pii]