Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Between biodiversity conservation and sustainable forest management – A multidisciplinary assessment of the emblematic Białowieża Forest case
    Blicharska, M. ; Angelstam, P. ; Giessen, L. ; Hilszczański, J. ; Hermanowicz, E. ; Holeksa, J. ; Jacobsen, J.B. ; Jaroszewicz, B. ; Konczal, A. ; Konieczny, A. ; Mikusiński, G. ; Mirek, Z. ; Mohren, F. ; Muys, B. ; Niedziałkowski, K. ; Sotirov, M. ; Stereńczak, K. ; Szwagrzyk, J. ; Winder, G.M. ; Witkowski, Z. ; Zaplata, R. ; Winkel, G. - \ 2020
    Biological Conservation 248 (2020). - ISSN 0006-3207
    Białowieża Forest - Biodiversity conservation - Conservation conflict - Forest management - Interdisciplinarity - Land use conflict - Sustainable land use

    The tension between biodiversity conservation and multipurpose forest management may lead to conflicts. An internationally prominent example is the Białowieża Forest Massif (BFM), an extensive forest complex with high levels of naturalness. We apply a systematic, multidisciplinary assessment process to review empirical evidence on different dimensions of the BFM conflict. While there is broad consensus that this forest massif is an exceptional place worth conserving and that a way forward is a zonation system combining conservation with management, exactly how this should be done has yet to be agreed upon. Our assessment shows that the key reasons for the BFM controversy go beyond the availability of knowledge on the ecological status of the BFM and include: 1) evidence stemming from different sources, which is often contradictory and prone to different interpretations; 2) knowledge gaps, particularly with regard to socio-economic drivers and beneficiaries as well as uncertainties about future trends; 3) fundamentally different values and priorities among stakeholder groups, resulting in power struggles, and an overall lack of trust. We conclude that evidence-based knowledge alone is insufficient to cope with complex conservation conflicts. While more evidence may help assess the consequences of decisions, the actual management decisions depend on different actors' worldviews, which are rooted in their professional identities and power, and their political and legal realities. This calls for conflict management through a well-organized participatory process organized and supervised by a body deemed legitimate by the groups involved.

    Methods to assess the effect of meat processing on viability of Toxoplasma gondii: towards replacement of mouse bioassay by in vitro testing
    Opsteegh, M. ; Dam-Deisz, C. ; Boer, Paulo de; Decraeye, S. ; Faré, Andrea ; Hengeveld, P. ; Luiten, R. ; Schares, Gereon ; Smits, C.B. ; Verhaegen, Bavo ; Verkleij, T.J. ; Giessen, Joke van der; Wisselink, Henk J. - \ 2020
    International Journal for Parasitology 50 (2020)5. - ISSN 0020-7519 - p. 357 - 369.
    Consumption of meat containing viable tissue cysts is considered one of the main sources of human infection with Toxoplasma gondii. In contrast to fresh meat, raw meat products usually undergo processing, including salting and mixing with other additives such as sodium acetate and sodium lactate, which affects the viability of T. gondii. However, the experiments described in the literature are not always performed in line with the current processing methods applied in industry. It was our goal to study the effect of salting and additives according to the recipes used by industrial producers. Mouse or cat bioassay is the ‘gold standard’ to demonstrate the presence of viable T. gondii. However, it is costly, time consuming and for ethical reasons not preferred for large-scale studies. Therefore, we first aimed to develop an alternative for mouse bioassay that can be used to determine the effect of processing on the viability of T. gondii tissue cysts. The assays studied were (i) a cell culture method to determine the parasite’s ability to multiply, and (ii) a propidium monoazide (PMA) dye-based assay to selectively detect DNA from intact parasites. Processing experiments were performed with minced meat incubated for 20 h with low concentrations of NaCl, sodium lactate and sodium acetate. NaCl appeared to be the most effective ingredient with only one or two out of eight mice infected after inoculation with pepsin-digest of portions processed with 1.0, 1.2 and 1.6% NaCl. Results of preliminary experiments with the PMA-based method were inconsistent and did not sufficiently discriminate between live and dead parasites. In contrast, the cell culture method showed promising results, but further optimization is needed before it can replace or reduce the number of mouse bioassays needed. In future, standardised in vitro methods are necessary to allow more extensive testing of product-specific processing methods, thereby providing a better indication of the risk of T. gondii infection for consumers.
    Effect of meat processing on viability of Toxoplasma gondii: Towards replacement of mouse bioassay by in vitro testing
    Opsteegh, M. ; Dam-Deisz, C. ; Boer, P. de; Fare, A. ; Hengeveld, P. ; Luiten, R. ; Smits, C.B. ; Verkleij, T. ; Giessen, Judith van der; Wisselink, H.J. - \ 2019
    Felines are the definitive hosts of T. gondii and primary infection results in fecal shedding of infectious oocysts. Infected intermediate hosts will develop tissue cysts, which are infective to both cats and intermediate hosts. Meat containing viable tissue cysts is considered one of the main sources of human infection. In contrast to fresh meat, raw meat products usually undergo processing, including salting and mixing in additives such as acetate and lactate, which affects the viability of T. gondii. However, the experiments currently described in literature, are not always performed in line with the processing methods applied in industry. Therefore we aimed to study the effect of salting and additives according to the recipes used by commercial producers. Mouse or cat bioassay is the gold standard to demonstrate the presence of viable T. gondii. However, it is costly, time consuming and for ethical reasons not preferred for large-scale studies. Therefore, our second aim was to develop an alternative for mouse bioassay that can be used to determine the effect of processing on the viability of T. gondii tissue cysts. We focused on a tissue culture method to determine the parasite's ability to multiply, and a PMA-based assay to selectively detect DNA from live cells. Results with the PMA-based method were inconsistent and did not sufficiently discriminate between live and dead parasites. The tissue culture method showed promising results, but further optimization is needed before it can replace or reduce the number of mouse bioassays needed. Small scale experiments with minced meat incubated for 20h with low concentrations of salt, lactate and acetate showed a large but incomplete reduction of the number of infected mice. In future, in vitro methods are needed to allow more extensive testing of product-specific processing methods, thereby providing a better indication of the risk of T. gondii infection for consumers.
    A risk based surveillance programme for Toxoplasma gondii in pigs using a combination of farm auditing and serological screening
    Wisselink, H.J. ; Swanenburg, M. ; Gonzales Rojas, Jose ; Asseldonk, M.A.P.M. van; Wagenberg, Coen van; Giessen, J. van der; Meerburg, B.G. ; Krijger, Inge ; Eppink, D.M. ; Bouwknegt, M. ; Oorburg, D. - \ 2019
    Toxoplasma gondii is recognized as one of the major foodborne pathogens with a high human disease burden. In the Netherlands, pork contributes to about 11 % of the meatborne T. gondii infections. To control T. gondii infections in pigs, EFSA has advised to perform serological testing of pigs and audits of pig farms on risk factors for T. gondii infection. In the Netherlands, a program was started to translate the EFSA advice into a practical risk based surveillance system. In first instance, a large scale serological monitoring of fattening pigs was started and seroprevalence over time was determined. Next, the association between within-herd seroprevalence and risk factors for T. gondii on fattening pig farms in the Netherlands was determined. For this, a questionnaire for auditing farms for the presence of risk factors of T. gondii was developed and used on 25 case and 50 control farms. Results show that there is a significant association between seroprevalence and risk factors as cats present on farms, use of unheated feed products and feeding wet feed. Moreover, on-farm presence of rats and mice also increases Toxoplasma transmission risks. Subsequently, a study was started on farms to quantify the effectiveness of interventions on farms. A cross-over clinical trial was set up in which case farms were their own control and the cross-over moment is the implementation of interventions on risk factors to change farm management. Farms with a high within-herd seroprevalence were followed for at least during a year and monitored periodically for seroprevalence and implementation of interventions to eventually reduce the disease burden. The break-even point was calculated for which the intervention cost at fattening pig farms equal averted human disease burden and averted cost-of-illness minus cost of the surveillance program. The results shows favourable economic perspectives for interventions to control pig meat-born transmission of T. gondii.
    Identification of potential risk factors for Toxoplasma gondii in fattening pigs in the Netherlands using a Bayesian approach
    Eppink, D.M. ; Bouwknegt, M. ; Oorburg, D. ; Urlings, H.A.P. ; Asseldonk, Marcel van; Wagenberg, Coen van; Krijger, Inge ; Giessen, J.W.P. van der; Swanenburg, M. ; Wisselink, H.J. - \ 2019
    Introduction
    Toxoplasma gondii is a relevant foodborne pathogen,it is estimated that up to one third of the worldpopulation has been exposed to the parasite (Tenteret al. 2000). In the Netherlands toxoplasmosis rankssecond on a list of prioritized emerging zoonosis(Havelaar et al. 2010) and also second in disease burden among 14 foodborne diseases (Mangen et al.2017). Data suggest that ingesting improperly cooked meat containing T. gondii is one of the major sources of infection in Europe and North America (Crotta et al. 2017; Guo et al. 2015). The contribution of pork to meatborne T. gondii infections is estimated to be11 % in the Netherlands (Opsteegh 2011) and is seen as an important possible source of human T. gondii infections (Foroutan et al. 2019). The European Food Safety Authority (EFSA) advised to perform serological testing of pigs and on farm audits on risk factors (EFSA 2011). To that end, a serological monitoring program was developed in a slaughterhouse in the Netherlands. In this study, the objective is to determine the association between within herd seroprevalence, corrected for misclassification of samples through Bayesian analyses, and risk factors for T. gondii on fattening pig farms in TheNetherlands.
    Materials and MethodsFrom 2015 to 2018, HACCP based audits were performedon 75 fattening pig farms in The Netherlands to identify the presence of potential T. gondii risk factors. All farms were conventional pig farms, with 15 farms being farrow to finish. As overall seroprevalence of T. gondii in pigs in the Netherlands is low, estimated at 5 % (1-12 % 95 % CI) by Foroutanet al. 2019, approached farms were chosen with the knowledge of previous serology data. In this way there would be farms with positive serum samples and farms without them included in the study. The audits were based on an updated version of the questionnaire from Mul et al. (2015) and covered the following topics: outdoor access, farm biosecurity, rodent control, presence of cats, feed and watersupply. In addition, serum samples (n=6272) from fattening pigs were obtained at slaughter throughout the year before the audit on the farm was performed. These samples were used for antibody testing bya PrioCHECK™ Toxoplasma Antibody ELISA. Data were analysed using Bayesian statistics, with the within farm T. gondii prevalence as dependent variable and potential risk factors as independent variables. As always with serology, misclassification due to false-positive or false-negative results can occur. Statistical methods have been developed to account for such misclassification, based on frequentistic as well as Bayesian approaches (Hui & Walter 1980; Josephet al. 1995). First, all independent variables wereanalysed in a univariate logistic model, and variables with a probability ≤0.25 that zero is included in the 95 % interval were analysed in a multivariable model. The multivariate logistic model was fitted using backward elimination until all remaining variables showed a probability ≤0.05 that zero is included in the 95 % interval. Two-way interaction terms were evaluated similarly to the main variables regarding statistical significance.
    ResultsDescriptive results showed that 50 out of the 75 farms had 1 or more positive serum samplein the year before the audit was performed. In total 438 samples were positive out of the 6272 samples. Final Bayesian analyses are currently being conducted. However, preliminary results from data analysis using frequentistic logistic multivariate regression identified two significant risk factors: the accessibility of pig feed for cats and theprovision of well water as drinking water for the pigs (Table 1).
    Discussion and ConclusionsThe use of serological testing seems to be a valuable guide and monitoring tool for the control of T.gondii in pork production. In a preliminary analysis, a higher within-herd T. gondii seroprevalence on fattening pig farms in the Netherlands was associated with the accessibility of pig feed for cats and the provision of well water as drinking water for the pigs. Improvements in farm management on fattening pig farms will likely contribute to reduction of the human disease burden and is presently studied.
    The relationship between the presence of antibodies and direct detection of Toxoplasma gondii in slaughtered calves and cattle in four European countries
    Opsteegh, M. ; Spano, F. ; Aubert, D. ; Balea, A. ; Burrells, A. ; Cherchi, S. ; Cornelissen, J.B.W.J. ; Dam-Deisz, C. ; Guitian, J. ; Györke, A. ; Innes, E.A. ; Katzer, F. ; Limon, G. ; Possenti, A. ; Pozio, E. ; Schares, G. ; Villena, I. ; Wisselink, H.J. ; Giessen, J.W.B. van der - \ 2019
    International Journal for Parasitology 49 (2019)7. - ISSN 0020-7519 - p. 515 - 522.
    Cattle - Detection - Mouse bioassay - PCR - Serology - Toxoplasma gondii

    In cattle, antibodies to Toxoplasma gondii infection are frequently detected, but evidence for the presence of T. gondii tissue cysts in cattle is limited. To study the concordance between the presence of anti-T. gondii IgG and viable tissue cysts of T. gondii in cattle, serum, liver and diaphragm samples of 167 veal calves and 235 adult cattle were collected in Italy, the Netherlands, Romania and the United Kingdom. Serum samples were tested for anti-T. gondii IgG by the modified agglutination test and p30 immunoblot. Samples from liver were analyzed by mouse bioassay and PCR after trypsin digestion. In addition, all diaphragms of cattle that had tested T. gondii-positive (either in bioassay, by PCR on trypsin-digested liver or serologically by MAT) and a selection of diaphragms from cattle that had tested negative were analyzed by magnetic capture quantitative PCR (MC-PCR). Overall, 13 animals were considered positive by a direct detection method: seven out of 151 (4.6%) by MC-PCR and six out of 385 (1.6%) by bioassay, indicating the presence of viable parasites. As cattle that tested positive in the bioassay tested negative by MC-PCR and vice-versa, these results demonstrate a lack of concordance between the presence of viable parasites in liver and the detection of T. gondii DNA in diaphragm. In addition, the probability to detect T. gondii parasites or DNA in seropositive and seronegative cattle was comparable, demonstrating that serological testing by MAT or p30 immunoblot does not provide information about the presence of T. gondii parasites or DNA in cattle and therefore is not a reliable indicator of the risk for consumers.

    Association between within-herd seroprevalence and risk factors for Toxoplasma gondii in fattening pigs in the Netherlands
    Eppink, D.M. ; Bouwknegt, M. ; Oorburg, D. ; Urlings, H.A.P. ; Asseldonk, Marcel van; Wagenberg, Coen van; Krijger, I.M. ; Giessen, J.W.P. Van der; Swanenburg, M. ; Wisselink, H.J. - \ 2018
    In: Annual General Meeting of the European College of Veterinary Public Health, "Fading of the HACCP after four decades: new trends in VPH for food safety ", Perugia, 17th-19th October 2018. - European College of Veterinary Public Health (ECVPH) - p. 40 - 40.
    Study on progress in implementing the EU Forest Strategy - Evaluation Study
    Wolfslehner, B. ; Aggestam, F. ; Hurmekoski, E. ; Kulikova, E. ; Lindner, Marcus ; Nabuurs, G.J. ; Pettenella, D. ; Pülzl, H. ; Giessen, L. ; Arets, E.J.M.M. ; Hendriks, C.M.A. - \ 2018
    European Forest Institute - ISBN 9789279864896 - 182 p.
    Serological screening of Dutch slaughter pigs to estimate the seroprevalence of Toxoplasma gondii infections at farms
    Swanenburg, M. ; Rojas, J.G. ; Bouwknegt, M. ; Oorburg, D. ; Giessen, Joke van der; Wisselink, H.J. - \ 2018
    In: The 15th international symposium of veterinary epidemiology and economics. - Chang Mai, Thailand : The World Organisation for Animal Health (OIE) - p. 252 - 252.
    Prevalence of Leptospira spp. and Seoul hantavirus in brown rats (Rattus norvegicus) in four regions in the Netherlands, 2011-2015
    Maas, Miriam ; Vries, Ankje De; Reusken, Chantal ; Buijs, Jan ; Goris, Marga ; Hartskeerl, Rudy ; Ahmed, Ahmed ; Tulden, Peter van; Swart, Arno ; Pijnacker, Roan ; Koene, Miriam ; Lundkvist, Åke ; Heyman, Paul ; Rockx, Barry ; Giessen, Joke Van Der - \ 2018
    Infection Ecology and Epidemiology 8 (2018)1. - ISSN 2000-8686
    epidemiology - hantavirus - Leptospirosis - prevalence - Rattus norvegicus - Seoul virus

    Background: Brown rats (Rattus norvegicus) may carry pathogens that can be a risk for public health. Brown rats in the Netherlands were tested for the zoonotic pathogens Leptospira spp. and Seoul hantavirus (SEOV), in order to obtain insight in their prevalence. Methods and results: Cross-sectional studies were performed at four locations from 2011 to 2015. The rats were tested for Leptospira spp. using real-time PCR and/or culture resulting in a prevalence ranging between 33–57%. Testing for SEOV was done through an adapted human Seoul hantavirus ELISA and real-time RT-PCR. Although at several locations the ELISA indicated presence of SEOV antibodies, none could be confirmed by focus reduction neutralization testing. Conclusion: The results indicate a widespread presence of Leptospira spp. in brown rats in the Netherlands, including areas with a low leptospirosis incidence in humans. No evidence for circulation of SEOV was found in this study.

    Brucella pinnipedialis in grey seals (Halichoerus grypus) and harbor seals (Phoca vitulina) in the Netherlands
    Kroese, Michiel V. ; Beckers, Lisa ; Bisselink, Yvette J.W.M. ; Brasseur, Sophie ; Tulden, Peter W. van; Koene, Miriam G.J. ; Roest, Hendrik I.J. ; Ruuls, Robin C. ; Backer, Jantien A. ; Ijzer, Jooske ; Giessen, Joke W.B. van der; Willemsen, Peter T.J. - \ 2018
    Journal of Wildlife Diseases 54 (2018)3. - ISSN 0090-3558 - p. 439 - 449.
    Brucella pinnipedialis - Halichoerus grypus - MALDI-TOF MS - Marine mammals - MLST - MLVA-16 - Phoca vitulina - The Netherlands

    Brucellosis is a zoonotic disease with terrestrial or marine wildlife animals as potential reservoirs for the disease in livestock and human populations. The primary aim of this study was to assess the presence of Brucella pinnipedialis in marine mammals living along the Dutch coast and to observe a possible correlation between the presence of B. pinnipedialis and accompanying pathology found in infected animals. The overall prevalence of Brucella spp. antibodies in sera from healthy wild grey seals (Halichoerus grypus; n=11) and harbor seals (Phoca vitulina; n=40), collected between 2007 and 2013 ranged from 25% to 43%. Additionally, tissue samples of harbor seals collected along the Dutch shores between 2009 and 2012, were tested for the presence of Brucella spp. In total, 77% (30/ 39) seals were found to be positive for Brucella by IS711 real-time PCR in one or more tissue samples, including pulmonary nematodes. Viable Brucella was cultured from 40% (12/30) real-time PCR-positive seals, and was isolated from liver, lung, pulmonary lymph node, pulmonary nematode, or spleen, but not from any PCR-negative seals. Tissue samples from lung and pulmonary lymph nodes were the main source of viable Brucella bacteria. All isolates were typed as B. pinnipedialis by multiple-locus variable number of tandem repeats analysis-16 clustering and matrix-assisted laser desorption ionization-time of flight mass spectrometry, and of sequence type ST25 by multilocus sequence typing analysis. No correlation was observed between Brucella infection and pathology. This report displays the isolation and identification of B. pinnipedialis in marine mammals in the Dutch part of the Atlantic Ocean.

    A cross sectional study on Dutch layer farms to investigate the prevalence and potential risk factors for different Chlamydia species
    Heijne, Marloes ; Goot, Jeanet A. van der; Fijten, Helmi ; Giessen, Joke W. van der; Kuijt, Eric ; Maassen, Catharina B.M. ; Roon, Annika van; Wit, Ben ; Koets, Ad P. ; Roest, Hendrik I.J. - \ 2018
    PLoS ONE 13 (2018)1. - ISSN 1932-6203
    In poultry several Chlamydia species have been detected, but Chlamydia psittaci and Chlamydia gallinacea appear to be most prevalent and important. Chlamydia psittaci is a well-known zoonosis and is considered to be a pathogen of poultry. Chlamydia gallinacea has been described more recently. Its avian pathogenicity and zoonotic potential have to be further elucidated. Within the Netherlands no data were available on the presence of Chlamydia on poultry farms. As part of a surveillance programme for zoonotic pathogens in farm animals, we investigated pooled faecal samples from 151 randomly selected layer farms. On a voluntary base, 69 farmers, family members or farm workers from these 151 farms submitted a throat swab. All samples were tested with a generic 23S Chlamydiaceae PCR followed by a species specific PCR for C. avium, C. gallinacea and C. psittaci. C. avium and psittaci DNA was not detected at any of the farms. At 71 farms the positive result could be confirmed as C. gallinacea. Variables significantly associated with the presence of C. gallinacea in a final multivariable model were ‘age of hens,’ ‘use of bedding material’ and ‘the presence of horses.’ The presence of C. gallinacea was associated with neither clinical signs, varying from respiratory symptoms, nasal and ocular discharges to diarrhoea, nor with a higher mortality rate the day before the visit. All throat swabs from farmers, family members or farm workers tested negative for Chlamydia DNA, giving no further indication for possible bird-to-human (or human-to-bird) transmission.
    Using serological monitoring, internet-based feedback and on-farm auditing to improve Toxoplasma gondii control at Dutch pig farms
    Oorburg, D. ; Eppink, Dorien ; Heijltjes, Janneke ; Bouwknegt, Martijn ; Urlings, Bert ; Giessen, Joke van der; Krijger, Inge ; Mul, Monique ; Swanenburg, M. ; Wisselink, H.J. - \ 2017
    In: 12th International Symposium on the Epidemiology and Control of Biological,Chemical and Physical Hazards in Pigs and Pork - Proceedings Book, Foz doIguaçu, august 21-24, 2017. - Embrapa - p. 201 - 201.
    Toxoplasma gondii is a relevant foodborne pathogen due to its human disease burden. In the Netherlands, pork is estimated to contribute to 11% of the meatborne T. gondii infections. The European Food Safety Authority advised to perform serological testing of pigs and on farm audits on risk factors for T. gondii infection.
    One health-samenwerking in de aanpak van psittacose
    Heijne, M. ; Hogerwerf, Lenny ; Dijkstra, Frederika ; Goot, J.A. van der; Heddema, Edou ; Kroneman, A. ; Notermans, D. ; Pannekoek, Yvonne ; Rosa, Mauro de; Wierik, M. te; Giessen, Joke van der; Roest, H.I.J. ; Hoek, Wim van der - \ 2017
    Nederlands Tijdschrift voor Medische Microbiologie 25 (2017)2. - ISSN 0929-0176 - p. 43 - 48.
    Psittacose is een zoönose veroorzaakt door de bacterie Chlamydia psittaci. In Nederland is psittacose bij mensen een meldingsplichtige en bij vogels (uitgezonderd pluimvee) een aangifteplichtige ziekte. Van 2011 tot 2015 werden 41 tot 70 humane meldingen per jaar gedaan, maar dit is een onderschatting. Het aantal pneumonieën veroorzaakt door C. psittaci wordt op 1500 per jaar geschat. In 2014 is het One Health-project Plat4m-2bt-Psittacosis gestart. In dit project wordt een onlineplatform ontwikkeld om uitwisseling van data te faciliteren en de samenwerking tussen het humane en veterinaire veld te verbeteren. Onderdeel van het project is het beter in kaart brengen van de aviaire bronnen van psittacose. Recent wordt, naast papegaaiachtigen en duiven, ook pluimvee als mogelijke bron van humane C. psittaci-infecties gezien. Op basis van de jaarlijkse humane psittacosemeldingen is, ook in Nederland, een link gelegd tussen psittacose en de aanwezigheid van kippenslachterijen en eendenbedrijven. Bij een Nederlandse studie op ongeveer 150 leghennenbedrijven is echter geen C. psittaci-DNA aangetoond, maar bij ongeveer de helft van de bedrijven wel een relatief nieuwe Chlamydia-soort: C. gallinacea. Het zoönotisch potentieel van C. gallinacea is nog onduidelijk. Met de ontwikkeling en toepassing van het onlineplatform wil het Platform-2bt-Psittacosis een voorbeeld vormen voor een structurele aanpak van de bestrijding van zoönosen.
    Environmental surveillance during an outbreak of tularaemia in hares, the Netherlands, 2015
    Janse, Ingmar ; Maas, M. ; Rijks, J.M. ; Koene, M. ; Plaats, R.Q. van der; Engelsma, M. ; Tas, P.W.L. ; Braks, M. ; Stroo, A. ; Notermans, D.W. ; Vries, M.C. de; Reubsaet, F.A.G. ; Fanoy, E. ; Swaan, C.M. ; Kik, M.J. ; Ijzer, J. ; Jaarsma, R.I. ; Wieren, S. van; Roda Husman, A.M. de; Passel, M. van; Roest, H. ; Giessen, J. van der - \ 2017
    Eurosurveillance 22 (2017)35. - ISSN 1025-496X
    Tularaemia, a disease caused by the bacterium Francisella tularensis, is a re-emerging zoonosis in the Netherlands. After sporadic human and hare cases occurred in the period 2011 to 2014, a cluster of F. tularensis-infected hares was recognised in a region in the north of the Netherlands from February to May 2015. No human cases were identified, including after active case finding. Presence of F. tularensis was investigated in potential reservoirs and transmission routes, including common voles, arthropod vectors and surface waters. F. tularensis was not detected in common voles, mosquito larvae or adults, tabanids or ticks. However, the bacterium was detected in water and sediment samples collected in a limited geographical area where infected hares had also been found. These results demonstrate that water monitoring could provide valuable information regarding F. tularensis spread and persistence, and should be used in addition to disease surveillance in wildlife.
    Knaagdieren & Zoönosen: Toxoplasma gondii
    Opsteegh, M. ; Giessen, J.W.B. van der; Meerburg, B.G. - \ 2016
    In: Staat van Zoönosen 2016 Bilthoven : RIVM (RIVM rapport 2017-0142) - p. 84 - 84.
    Identification of pig farms with a high risk for Toxoplasma gondii using a combination of serological monitoring and auditing
    Wisselink, H.J. ; Swanenburg, M. ; Gonzales Rojas, Jose ; Asseldonk, Marcel van; Wagenberg, Coen van; Giessen, J.W.B. van der; Mul, M.F. ; Klein Koerkamp, M. ; Oorburg, D. - \ 2016
    In: 4th EAVLD Congress of the European Association of Veterinary Laboratory Diagnosticians. - Prague : European Association of Veterinary Laboratory Diagnosticians (4th EAVLD Congress of the European Association of Veterinary Laboratory Diagnosticians ) - p. 42 - 42.
    Implementing wildlife disease surveillance in the Netherlands, a One Health approach
    Maas, M. ; Gröne, A. ; Kuiken, T. ; Schaik, G. Van; Roest, H.I.J. ; Giessen, J.W.B. Van Der - \ 2016
    Revue scientifique et technique / Office International des Epizooties 35 (2016)3. - ISSN 0253-1933 - p. 863 - 874.
    One health - Overview - Public health - Surveillance - The Netherlands - Veterinary health - Wildlife disease
    The surveillance of (emerging) wildlife diseases can provide important, objective evidence of the circulation of pathogens of interest for veterinary and/or public health. The involvement of multiple research institutions in wildlife disease surveillance can ensure the best use of existing knowledge and expertise, but can also complicate or add challenges to the integration of wildlife disease surveillance components into a national programme. Documenting the existing efforts in a country's surveillance of wildlife diseases, including the institutes in which it takes place, provides a basis for policy-makers and authorities to identify gaps and priorities in their current surveillance programmes. This paper describes the wildlife disease surveillance activities taking place in the Netherlands. The authors recommend that, in addition to funding these current activities, surveillance resources should be allocated with the flexibility to allow for additional targeted surveillance, to detect and adequately respond to newly introduced or emerging pathogens. Similar structured overviews of wildlife disease surveillance in other countries would be very useful to facilitate international collaboration.
    Tularemie in Nederland, terug van weggeweest?
    Pijnacker, Roan ; Koene, M.G.J. ; Rijks, J.M. ; Swaan, C.M. ; Maas, M. ; Rosa, M. de; Broens, E.M. ; Fanoy, E. ; Vries, M.C. de; Notermans, D.W. ; Tas, P. v.d.; Gröne, A. ; Roest, H.I.J. ; Pelt, W. van; Giessen, J. van der - \ 2016
    Nederlands Tijdschrift voor Medische Microbiologie 24 (2016)2. - ISSN 0929-0176 - p. 65 - 68.
    Tularemie is een bacteriële zoönose veroorzaakt door Francisella tularensis. De ziekte kent verschillende verschijningsvormen, dierlijke reservoirs en transmissieroutes. De bacterie kan zich maandenlang handhaven buiten
    een dierlijke gastheer. Na decennialange afwezigheid in Nederland is tularemie vanaf 2011 incidenteel aangetoond bij zowel hazen als mensen. Begin 2015 was er een opvallend hoge sterfte onder hazen in de omgeving van Akkrum in Friesland. In dit gebied werd bij 11 hazen tularemie aangetoond. In dit artikel bespreken we de achtergrond en de huidige situatie van tularemie in Nederland
    Coronary microvascular dysfunction after long-term diabetes and hypercholesterolemia
    Sorop, Oana ; Heuvel, Mieke van den; Ditzhuijzen, Nienke S. van; Beer, Vincent J. de; Heinonen, Ilkka ; Duin, Richard W.B. van; Zhou, Zhichao ; Koopmans, Sietse J. ; Merkus, Daphne ; Giessen, Wim J. van der - \ 2016
    American Journal of Physiology : Heart and Circulatory Physiology 311 (2016)6. - ISSN 0363-6135 - p. H1339 - H1351.
    Coronary microvascular dysfunction - Diabetes - Endothelin-1 - Hypercholesterolemia - Swine

    Coronary microvascular dysfunction (CMD) has been proposed as an important component of diabetes mellitus (DM)-and hypercholesterolemia-associated coronary artery disease (CAD). Previously we observed that 2.5 mo of DM and high-fat diet (HFD) in swine blunted brady-kinin (BK)-induced vasodilation and attenuated endothelin (ET)-1-mediated vasoconstriction. Here we studied the progression of CMD after 15 mo in the same animal model of CAD. Ten male swine were fed a HFD in the absence (HFD, n = 5) or presence of streptozotocin-induced DM (DM + HFD. n = 5). Responses of small (~300-μm-diameter) coronary arteries to BK. ET-1. and the nitric oxide (NO) donor 5-nitroso-N-acetylpenicillamine were examined in vitro and compared with those of healthy (Normal) swine (n = 12). Blood glucose was elevated in DM + HFD (17.6 ± 4.5 mmol/1) compared with HFD (5.1 ± 0.4 mmol/1) and Normal (5.8 ± 0.6 mmol/1) swine, while cholesterol was markedly elevated in DM + HFD (16.8 ± 1.7 mmol/1) and HFD (18.1 ±2.6 mmol/1) compared with Normal (2.1 ± 0.2 mmol/1) swine (all P <0.05). Small coronary arteries showed early atherosclerotic plaques in HFD and DM + HFD swine. Surprisingly. DM + HFD and HFD swine maintained BK responsiveness compared with Normal swine due to an increase in NO availability relative to endothelium-derived hyperpolarizing factors. However, ET-1 responsiveness was greater in HFD and DM + HFD than Normal swine (both P <0.05), resulting mainly from ΕΤ» receptor-mediated vasoconstriction. Moreover, the calculated vascular stiffness coefficient was higher in DM + HFD and HFD than Normal swine (both P <0.05). In conclusion. 15 mo of DM + HFD, as well as HFD alone, resulted in CMD. Although the overall vasodilation to BK was unperturbed, the relative contributions of NO and endothelium-de-rived hyperpolarizing factor pathways were altered. Moreover, the vasoconstrictor response to ET-1 was enhanced, involving the ΕΤB receptors. In conjunction with our previous study, these findings highlight the time dependence of the phenotype of CMD.

    The Role of Farm Management Characteristics in Understanding the Spatial Distribution of Landscape Elements: A Case Study in the Netherlands
    Hauser, Leon Tobias ; Sluis, T. van der; Giessen, M. - \ 2016
    Rural Landscapes: Society Environment, History 3 (2016)1. - ISSN 2002-0104 - 15 p.
    In Western Europe the fate of biodiversity is intimately linked to agricultural land use. A driving force behind biodiversity decline is the gradual conversion of Europe’s traditional integrated rural landscapes of nature and agriculture into monofunctional units of production. With these developments, semi-natural landscape elements have increasingly disappeared from agricultural landscapes. A growing body of research, however, underlines the importance of semi-natural habitats in agricultural landscapes for biodiversity conservation, habitat connectivity, and ecosystem services. On the local scale, considerable variation between the relative area of landscape elements on individual farms can be observed. Farm management decisions are presumed to be important determinants for the composition of agricultural landscapes and the services provided to society.
    By bringing together data from farmer interviews and aerial photographic imagery, this paper analyzes the predictive validity of farm management characteristics to understand the distribution of landscape elements on farmland parcels. The farm management parameters included in the study are relevant to current dominant trends in the Dutch agricultural sector; intensification, scale enlargement, diversification, and gradual termination of farming activities. Scale enlargement and migratory processes are found to be important predictors. The results of the Dutch case study provide insights in the threats and opportunities for the conservation of semi-natural habitat in agricultural landscapes. The findings present an empirical contribution to the debate on sustainable management of agriculture’s green infrastructure and, in broader perspective, the objective to reconcile agricultural production with the urging need of biodiversity conservation in Europe’s spatially contested countryside.
    Marked increase in leptospirosis infections in humans and dogs in the Netherlands, 2014
    Pijnacker, Roan ; Goris, M.G. ; Wierik, M.J. te; Broens, E.M. ; Giessen, J.W. van der; Rosa, M. de; Wagenaar, J.A. ; Hartskeerl, R.A. ; Notermans, D.W. ; Maassen, K. ; Schimmer, B. - \ 2016
    Eurosurveillance 21 (2016)17. - ISSN 1025-496X - 7 p.

    In the Netherlands, 97 human leptospirosis cases were notified in 2014. This represents a 4.6-fold increase in autochthonous cases (n = 60) compared with the annual average between 2010 and 2013. Most cases had symptom onset between June and November. This marked increase in humans coincided with an increase of leptospirosis in dogs. In 2014, 13 dogs with leptospirosis were reported, compared with two to six dogs annually from 2010 to 2013. The majority of the autochthonous cases (n = 20) were linked to recreational exposure, e.g. swimming or fishing, followed by occupational exposure (n = 15). About sixty per cent (n = 37) of the autochthonous cases were most likely attributable to surface water contact, and 13 cases to direct contact with animals, mainly rats. A possible explanation for this increase is the preceding mild winter of 2013–2014 followed by the warmest year in three centuries, possibly enabling rodents and Leptospira spp. to survive better. A slight increase in imported leptospirosis was also observed in Dutch tourists (n = 33) most of whom acquired their infection in Thailand (n = 18). More awareness and early recognition of this mainly rodent-borne zoonosis by medical and veterinary specialists is warranted.

    Identifying pig herds at risk for Toxoplasma gondii: prevalence and test characteristics
    Boender, G.J. ; Swanenburg, M. ; Koeijer, A.A. de; Heres, L. ; Giessen, J.W.B. van der; Wisselink, H.J. - \ 2015
    In: Proceedings: Apicomplexa in farm animals. - Edinburgh : Moredun Research Institute - p. 55 - 55.
    Toxoplasma gondii in European slaughtered calves and cattle - serology, mouse bioassay and magnetic capture qPCR
    Opsteegh, M. ; Aubert, Dominique ; Balea, Anamaria ; Burrells, Alison ; Cherchi, S. ; Cornelissen, J.B.W.J. ; Dam, C. ; Györke, Adriana ; Kalmar, Zsuzsa ; Katzer, Frank ; Limon, Georgina ; Possenti, A. ; Pozio, Edoardo ; Spano, Furio ; Villena, Isabelle ; Wisselink, H.J. ; Giessen, J. van der - \ 2015
    In: ApiCOWplaxa 2015 Proceedings: Apicomplexa in Farm Animals. - Edinburgh : Moredun Research Institute - p. 43 - 43.
    Public and animal health risk of import and transit of live exotic animals into the Netherlands in the period 2013 and 2014
    Roon, A. van; Maas, M. ; Toale, D. ; Giessen, J. van der; Vos-de Jong, C.J. de; Swanenburg, M. ; Tafro, N. - \ 2015
    Central Veterinary Institute of Wageningen UR (Report / CVI 15/CVI0318) - 147 p.
    Letter to the editor: Inoculation of mice with avian blaCTX-M-1- or blaCMY-2-carrying Escherichia coli strains does not lead to long-term colonization
    Duijkeren, Engeline van; Overbeek, Wendy M. van; Huijbers, Patricia M.C. ; Giessen, Arjen W. van de; Hoek, Angela H.A.M. van - \ 2015
    Journal of Antimicrobial Chemotherapy 70 (2015)11. - ISSN 0305-7453 - p. 3164 - 3165.
    Onderzoek naar Brucella bij wilde zwijnen op de Veluwe
    Tulden, P.W. van; Dekkers, L.J.M. ; Giessen, J. van der - \ 2015
    Jacht & Beheer (2015). - ISSN 1569-3414 - p. 14 - 14.
    Tularemie in Nederland, terug van weggeweest?
    Koene, M.G.J. ; Rijks, J. ; Maas, M. ; Rosa, M. de; Broens, E.M. ; Vellema, P. ; Engelsma, M.Y. ; Pijnacker, R. ; Fanoy, E. ; Notermans, D.W. ; Tas, P. van de; Giessen, J. van der; Gröne, A. ; Roest, H.I.J. - \ 2015
    Tijdschrift voor Diergeneeskunde 140 (2015)8. - ISSN 0040-7453 - p. 23 - 27.
    dierenwelzijn - diergezondheid - wilde dieren - animal welfare - animal health - wild animals
    Tularemie is een zoönose veroorzaakt door de
    bacterie Francisella tularensis. Veel diersoorten
    kunnen besmet raken, al bestaan er grote verschillen
    in gevoeligheid. Haasachtigen en knaagdieren
    zijn erg bevattelijk voor de infectie. Tussen
    1953 en 2011 zijn geen Nederlandse gevallen
    gediagnosticeerd, maar nadien zijn bij zowel
    hazen als mensen meerdere incidentele besmettingen
    aangetoond. Begin 2015 is tularemie vastgesteld
    bij meerdere dood aangetroffen hazen in
    de omgeving van Akkrum in Friesland. Bovendien
    werd in deze omgeving melding gemaakt
    van een hogere sterfte onder hazen dan gebruikelijk.
    Voor Nederland is dit een uitzonderlijke
    situatie. Dit artikel gaat dieper in op de ziekte
    en mogelijke risico’s voor dieren
    Kwaliteit van modellen voor wettelijke onderzoekstaken
    Houweling, H. ; Voorn, G.A.K. van; Giessen, A. van der; Wiertz, J. - \ 2015
    Wageningen : WOT Natuur & Milieu - Wageningen UR (WOt-paper 38) - 4
    kwaliteitsnormen - modellen - recht - natuur - milieu - landbouwwetenschappen - landschap - evaluatie - quality standards - models - law - nature - environment - agricultural sciences - landscape - evaluation
    De unit Wettelijke Onderzoekstaken Natuur & Milieu van Wageningen UR (WOT N&M) zet modellen, (ruimtelijke) gegevensbestanden en graadmeters in bij het beleidsgericht onderzoek voor het Planbureau voor de Leefomgeving en het Ministerie van Economische Zaken. Het gaat daarbij bijvoorbeeld om onderzoek voor de Natuurverkenningen, de Herijking van de Ecologische Hoofdstructuur of de Evaluatie van het Mest- en Gewasbeschermingsmiddelenbeleid. Om de kwaliteit van deze modellen en (ruimtelijke) gegevensbestanden te verbeteren en te borgen maakt de WOT N&M gebruik van een kwaliteitssysteem. In deze WOtpaper wordt dit kwaliteitssysteem toegelicht.
    Quality of models for policy support
    Houweling, H. ; Voorn, G.A.K. van; Giessen, A. van der; Wiertz, J. - \ 2015
    Wageningen : Statutory Research Tasks Unit for Nature & the Environment (WOT Natuur & Milieu) (WOt-paper 38) - 4
    quality management - policy - quality standards - models - kwaliteitszorg - beleid - kwaliteitsnormen - modellen
    The Statutory Research Tasks Unit for Nature & the Environment (WOT N&M) at Wageningen UR uses models, geodatabases and indicators in its policyoriented research for PBL Netherlands Environmental Assessment Agency (see Bouwma et al., 2014) and the Dutch Ministry of Economic Affairs. This research is undertaken for a variety of purposes, for example for the Nature Outlook reports, the review of the National Ecological Network and the evaluation of the policy on fertilisers and crop protection products. WOT N&M operates a quality system to improve and maintain the quality of these models and databases. This WOt-Paper describes this quality system.
    Increasing representation of states by utilitarian as compared to environmental bureaucracies in international forest and forest-environmental policy negotiations
    Giessen, L. ; Krott, M. ; Mollmann, T. - \ 2014
    Forest Policy and Economics 38 (2014). - ISSN 1389-9341 - p. 97 - 104.
    nature conservation policy - institutional change - governance - regime - politics - sectors - back
    This article analyses the representation of selected countries (EU-27 and the five influential "forest states") to international forest-related negotiations by national utilitarian vis-a-vis conservation-oriented ministerial bureaucracies. It is hypothesised that due to the bureaucracies' informal goal of gaining and maintaining responsibility over political issues, mainly ministries of agriculture including forestry and ministries of environment are competing for the task of representing states in international forest and forest-environmental negotiations. A survey design based on a semi-structured questionnaire was used to study the bureaucratic representation of the selected states to the United Nations Forum on Forests (UNFF) and to the Convention on Biological Diversity (CBD) negotiations between 2000 and 2011. The results show that in the processes under study the representation of states by utilitarian types of bureaucracies is rather increasing, while the role of conservationist bureaucracies is declining. Likewise, the roles of ministries of foreign affairs and economic affairs are declining, while hybrid organisations on agriculture/environment were observed being on a strong increase. Under CBD negotiations the vast majority of responding countries was represented by environmental bureaucracies, while agricultural ones played a marginal role. In contrast, under UNFF negotiations countries were represented by agricultural, economic and hybrid agricultural/environmental bureaucracies in approx. equal shares. Agricultural bureaucracies especially gained influence under UNFF negotiations during the study period. The article concludes on these trends also highlighting options for future research. (C) 2013 Elsevier B.V. All rights reserved.
    Identification and typing of Brucella spp. in stranded harbour porpoises (Phocoena phocoena) on the Dutch coast.
    Maio, E. ; Begeman, L. ; Bisselink, Y.J.W.M. ; Tulden, P.W. van; Wiersma, L. ; Hiemstra, S. ; Ruuls, R. ; Gröne, A. ; Roest, H.I.J. ; Willemsen, P.T.J. ; Giessen, J. van der - \ 2014
    Veterinary Microbiology 173 (2014)1-2. - ISSN 0378-1135 - p. 118 - 124.
    marine mammal brucella - north-sea - adjacent waters - infection - pinnipedialis - ceti - cetaceans - lungworms - emphasis - exposure
    The presence of Brucella (B.) spp. in harbour porpoises stranded between 2008 and 2011 along the Dutch coast was studied. A selection of 265 tissue samples from 112 animals was analysed using conventional and molecular methods. In total, 4.5% (5/112) of the animals corresponding with 2.3% (6/265) Brucella positive tissue samples were Brucella positive by culture and these were all confirmed by real-time polymerase chain reaction (real-time PCR) based on the insertion element 711 (IS711). In addition, two more Brucella-positive tissue samples from two animals collected in 2011 were identified using real-time PCR resulting in an overall Brucella prevalence of 6.3% (7/112 animals). Brucella spp. were obtained from lungs (n=3), pulmonary lymph node (n=3) and lungworms (n=2). Multi Locus Variable Number of Tandem Repeats (VNTR) Analysis (MLVA) typing based on the MLVA-16 showed that the Brucella isolates were B. ceti. Additional in silico Multi Locus Sequence typing (MLST) after whole genome sequencing of the 6 Brucella isolates confirmed B. ceti ST 23. According to the Brucella 2010 MLVA database, the isolated Brucella strains encountered were of five genotypes, in two distinct subclusters divided in two different time periods of harbour porpoises collection. This study is the first population based analyses for Brucella spp. infections in cetaceans stranded along the Dutch coast.
    Actor-centred power: The driving force in decentralised community based forest governance
    Krott, M. ; Bader, A. ; Schusser, C. ; Devkota, R. ; Maryudi, A. ; Giessen, L. ; Aurenhammer, H. - \ 2014
    Forest Policy and Economics 49 (2014). - ISSN 1389-9341 - p. 34 - 42.
    policy - science
    Community forestry has been described as a decentralised mode of forest governance that only partly lives up to its expectations. The power of important actors to misuse the community forestry approach for their self-interests has been reported as a major obstacle to comprehensive success. Hence, this article aims at developing an analytical, theory-based and empirically applicable framework for assessing an actor's power using community forestry as an illustrative case. The actor-centred power approach (ACP) analysis aims to provide a scientific answer to the question of who are the politically most powerful actors in community forestry practices. In making use of suitable components of power theories it builds strongly upon the social relations of actors, organisational aspects and power sources, as described by Weber, Dahl, Etzioni and their adherents. Actor-centred power approach (ACP) is defined as a social relationship in which actor A alters the behaviour of actor B without recognising B's will. In our framework we distinguish between three core elements: coercion, (dis-)incentives and dominant information. These make up the basis for observable facts that involve not only physical actions but also threats by power elements and the very sources of said power elements. Theoretical considerations show that, despite the focus being on actors, by looking to their power sources a considerable part of structural power can be more tangible at least in part, like rules, discourse or ideologies. Furthermore, the paper shows how the actor-centred power approach distinguishes power from other influences on forest management and contributes to the identification of the group of powerful actors on an empirical basis. Due to the focus on actors and well-defined and observable elements of power, the actor-centred power approach (ACP) could serve not only as a basis for research but also as a tool for quick assessment of power networks, delivering valuable preliminary information for designing forest policy in practice.
    Learning from practices — implications of the “practice based approach” for forest and environmental policy research.
    Giessen, L. ; Krott, M. - \ 2014
    Forest Policy and Economics 49 (2014). - ISSN 1389-9341 - p. 12 - 16.
    With the book publication “Forest and Nature Governance — A practice based approach” (Arts et al., 2013, Eds.) the Forest and Nature Conservation Policy Group of Wageningen University, The Netherlands demonstrates its high aspirations of developing a new research approach. This article aims at discussing the methodological and conceptual contributions of the book to the field of forest and environmental policy research and proposes perspectives for further developing this methodological approach. It finds the “practice based approach” being an innovative, theoretically sound concept, which is able to produce valuable and “thick” empirical results. The approach is also found offering a plethora of possibilities to link up to analytical policy research. Yet, the approach will require further elaboration, especially on questions regarding the role of definitions, its contribution towards explaining social phenomena, and concerning the use of normative orientations in some of the empirical cases. The future challenges of the approach lie in either moulding a niche for further developing it independent from other schools, or in influencing mainstream approaches through theoretical innovations or surprising empirical results.
    Significant increase of Echinococcus multilocularis prevalencein foxes, but no increased predicted risk for humans
    Maas, M. ; Dam-Deisz, W.D.C. ; Roon, A.M. van; Takumi, K. ; Giessen, J.W.B. van der - \ 2014
    Veterinary Parasitology 206 (2014)3-4. - ISSN 0304-4017 - p. 167 - 172.
    human alveolar echinococcosis - red foxes - netherlands - transmission - switzerland - city - dogs
    The emergence of the zoonotic tapeworm Echinococcus multilocularis, causative agent ofalveolar echinococcosis (AE), poses a public health risk. A previously designed risk mapmodel predicted a spread of E. multilocularis and increasing numbers of alveolar echinococ-cosis patients in the province of Limburg, The Netherlands. This study was designed todetermine trends in the prevalence and worm burden of E. multilocularis in foxes in a popu-lar recreational area in the southern part of Limburg to assess the risk of infection for humansand to study the prevalence of E. multilocularis in dogs in the adjacent city of Maastricht.Thirty-seven hunted red foxes were tested by the intestinal scraping technique and nestedPCR on colon content. Additionally, 142 fecal samples of domestic dogs from Maastrichtwere analyzed by qPCR for the presence of E. multilocularis.In foxes, a significantly increased prevalence of 59% (95% confidence interval 43–74%)was found, compared to the prevalence of 11% (95% CI 7–18%) in 2005–2006. Average wormburden increased to 37 worms per fox, the highest since the first detection, but consistentwith the prediction about the parasite population for this region. Updated prediction onthe number of AE cases did not lead to an increase in previous estimates of human AE casesup to 2018. No dogs in the city of Maastricht tested positive, but results of questionnairesshowed that deworming schemes were inadequate, especially in dogs that were consideredat risk for infection.
    An experimental Toxoplasma gondii dose response challenge model to study therapeutic or vaccine efficacy in cats
    Cornelissen, J.B.W.J. ; Giessen, J.W.B. van der; Takumi, K. ; Teunis, P.F.M. ; Wisselink, H.J. - \ 2014
    PLoS ONE 9 (2014)9. - ISSN 1932-6203 - 9 p.
    crude rhoptry proteins - united-states - tissue cysts - oocysts - bradyzoites - infectivity - tachyzoites - outbreak - animals - humans
    High numbers of Toxoplasma gondii oocysts in the environment are a risk factor to humans. The environmental contamination might be reduced by vaccinating the definitive host, cats. An experimental challenge model is necessary to quantitatively assess the efficacy of a vaccine or drug treatment. Previous studies have indicated that bradyzoites are highly infectious for cats. To infect cats, tissue cysts were isolated from the brains of mice infected with oocysts of T. gondii M4 strain, and bradyzoites were released by pepsin digestion. Free bradyzoites were counted and graded doses (1000, 100, 50, 10), and 250 intact tissue cysts were inoculated orally into three cats each. Oocysts shed by these five groups of cats were collected from faeces by flotation techniques, counted microscopically and estimated by real time PCR. Additionally, the number of T. gondii in heart, tongue and brains were estimated, and serology for anti T. gondii antibodies was performed. A Beta-Poisson dose-response model was used to estimate the infectivity of single bradyzoites and linear regression was used to determine the relation between inoculated dose and numbers of oocyst shed. We found that real time PCR was more sensitive than microscopic detection of oocysts, and oocysts were detected by PCR in faeces of cats fed 10 bradyzoites but by microscopic examination. Real time PCR may only detect fragments of T. gondii DNA without the presence of oocysts in low doses. Prevalence of tissue cysts of T. gondii in tongue, heart and brains, and anti T. gondii antibody concentrations were all found to depend on the inoculated bradyzoite dose. The combination of the experimental challenge model and the dose response analysis provides a suitable reference for quantifying the potential reduction in human health risk due to a treatment of domestic cats by vaccination or by therapeutic drug application.
    Circulation of four Anaplasma phagocytophilum ecotypes in Europe
    Jahfari, S. ; Coipan, E.C. ; Fonville, M. ; Leeuwen, A.D. van; Hengeveld, P. ; Heylen, D. ; Heyman, P. ; Maanen, C. van; Butler, C.M. ; Foldvari, G. ; Szekeres, S. ; Duijvendijk, L.A.G. van; Tack, W. ; Rijks, J.M. ; Giessen, J. van der; Takken, W. ; Wieren, S.E. van; Takumi, K. ; Sprong, H. - \ 2014
    Parasites & Vectors 7 (2014)1. - ISSN 1756-3305
    candidatus neoehrlichia mikurensis - human granulocytic anaplasmosis - ixodes-ricinus ticks - borrelia-burgdorferi - borne diseases - phylogenetic analyses - sequence-analysis - ehrlichiosis - strains - gene
    Background: Anaplasma phagocytophilum is the etiological agent of granulocytic anaplasmosis in humans and animals. Wild animals and ticks play key roles in the enzootic cycles of the pathogen. Potential ecotypes of A. phagocytophilum have been characterized genetically, but their host range, zoonotic potential and transmission dynamics has only incompletely been resolved. Methods. The presence of A. phagocytophilum DNA was determined in more than 6000 ixodid ticks collected from the vegetation and wildlife, in 289 tissue samples from wild and domestic animals, and 69 keds collected from deer, originating from various geographic locations in The Netherlands and Belgium. From the qPCR-positive lysates, a fragment of the groEL-gene was amplified and sequenced. Additional groEL sequences from ticks and animals from Europe were obtained from GenBank, and sequences from human cases were obtained through literature searches. Statistical analyses were performed to identify A. phagocytophilum ecotypes, to assess their host range and their zoonotic potential. The population dynamics of A. phagocytophilum ecotypes was investigated using population genetic analyses. Results: DNA of A. phagocytophilum was present in all stages of questing and feeding Ixodes ricinus, feeding I. hexagonus, I. frontalis, I. trianguliceps, and deer keds, but was absent in questing I. arboricola and Dermacentor reticulatus. DNA of A. phagocytophilum was present in feeding ticks and tissues from many vertebrates, including roe deer, mouflon, red foxes, wild boar, sheep and hedgehogs but was rarely found in rodents and birds and was absent in badgers and lizards. Four geographically dispersed A. phagocytophilum ecotypes were identified, that had significantly different host ranges. All sequences from human cases belonged to only one of these ecotypes. Based on population genetic parameters, the potentially zoonotic ecotype showed significant expansion. Conclusion: Four ecotypes of A. phagocytophilum with differential enzootic cycles were identified. So far, all human cases clustered in only one of these ecotypes. The zoonotic ecotype has the broadest range of wildlife hosts. The expansion of the zoonotic A. phagocytophilum ecotype indicates a recent increase of the acarological risk of exposure of humans and animals.
    The Dutch Q fever situation - Lessons learned?
    Roest, H.I.J. ; Maassen, C.B.M. ; Giessen, A. van de; Zijderveld, F.G. van - \ 2014
    Planet@Risk 2 (2014)3. - ISSN 2296-8172 - p. 166 - 168.
    About 60 to 75% of the emerging infectious diseases are zoonotic. A special group of zoonotic diseases are these that are endemic but in a dormant state. A good example of such a disease is Q fever in the Netherlands. Before 2005, Q fever was known to be present in the human and animal populations but did not cause significant disease. This changed in 2005, when the first abortions in dairy goats were registered and in 2007 when the first human Q fever outbreak in the Netherlands was recorded. Between 2005 and 2009 abortions on 28 dairy goat farms and 2 dairy sheep farms were detected and between 2007 and 2010 about 4000 human cases were notified. This is recognised as the largest laboratory confirmed Q fever outbreak ever reported. To identify the cause of the human disease, genotyping of the causative Q fever agent Coxiella burnetii confirmed the epidemiological link between humans and dairy goats and sheep. Furthermore, an intergraded human-veterinary approach was needed to combat the outbreak. The need for such a One Health approach was also the conclusion of the official evaluation of the Q fever outbreak in the Netherlands. This resulted in a currently implemented national zoonosis structure with a signalling forum that meets monthly. This structure has already been helpful in assessing the human risk of the Schmallenberg virus outbreak.
    Discussing legal scholarship from political science perspectives : Review
    Edwards, P. ; Giessen, L. - \ 2014
    Forest Policy and Economics 38 (2014). - ISSN 1389-9341 - p. 30 - 31.
    Scholarship in international law aims at addressing global forest governance comprehensively. This article reviews the recent contribution Global Forest Governance — Legal Concepts and Policy Trends by Rowena Maguire and puts it into the perspective of recent political and policy science research on global forests. While finding Maguire's volume being a very timely and valuable contribution to the interdisciplinary discussions on international forest governance, we identify some weaknesses which are mostly rooted in methodological critique and a lack of a systematic framework for analysis.
    Reviewing the main characteristics of the international forest regime complex and partial explanations for its fragmentation
    Giessen, L. - \ 2013
    International Forestry Review 15 (2013)1. - ISSN 1465-5489 - p. 60 - 70.
    global governance - climate-change - united-nations - policy - partnerships - lessons - back
    The objectives of this review article are, firstly, to provide an overview of the literature on the main characteristics of what is referred to as the international forest regime and secondly, based on this, to review explanations for fragmentation as its core characteristic. A third aim of the article is to propose fields for future policy-oriented research on global forest governance, the international forest regime and its fragmentation. The article discusses different strands of literature and academic views on the existence and main characteristics of an international forest regime. It regards the recent notion of an international forest regime complex to be a fruitful topic for future research proposals and finds that fragmentation is its analytical core characteristic. In addition, the article reviews partial explanations for the great relevance of fragmentation in the case of the forest regime complex. It discriminates between domestic factors and causes as opposed to those resulting from the international system. Based on the review, the article suggests, lastly, fields for future research on global forest governance, the international forest regime complex and its fragmentation.
    Tularaemia in a brown hare (lepus europaeus) in 2013: first case in the netherlands in 60 years
    Rijks, J.M. ; Kik, M. ; Koene, M.G.J. ; Engelsma, M.Y. ; Tulden, P.W. van; Montizaan, M.G. ; Oomen, T. ; Spierenburg, M.A.H. ; Ijzer, J. ; Giessen, J.W.B. van der; Gröne, A. ; Roest, H.I.J. - \ 2013
    Eurosurveillance 18 (2013)49. - ISSN 1025-496X
    Tularaemia has not been reported in Dutch wildlife since 1953. To enhance detection, as of July 2011, brown hares (Lepus europaeus) submitted for post-mortem examination in the context of non-targeted wildlife disease surveillance, were routinely tested for tularaemia by polymerase chain reaction (PCR). Francisella tularensis subspecies holarctica infection was confirmed in a hare submitted in May 2013. The case occurred in Limburg, near the site of the 1953 case. Further surveillance should clarify the significance of this finding.
    Geodemographic analysis of Borrelia burgdorferi sensu lato using the 5S-23S rDNA spacer region
    Coipan, E.C. ; Fonville, M. ; Tijsse-Klasen, E. ; Giessen, J.W.B. van der; Takken, W. ; Sprong, H. ; Takumi, K. - \ 2013
    Infection, Genetics and Evolution 17 (2013). - ISSN 1567-1348 - p. 216 - 222.
    ixodes-ricinus ticks - lyme borreliosis - clinical-manifestations - genetic-variability - population-genetics - housekeeping genes - sequence-analysis - bloodmeal source - borne diseases - netherlands
    Background: Lyme borreliosis is the predominant tick-borne disease in the Northern hemisphere, with considerable heterogeneity in clinical manifestations. Here, we evaluated one genetic marker for its use in population genetic based analysis. For that we collected molecular and epidemiological records of Borrelia burgdorferi sensu lato isolates from ticks, animals and humans at various sites in The Netherlands and worldwide. Methods: The 5S-23S rDNA (rrfA-rrlB) intergenic spacer region (IGS) from 291 Dutch Borrelia positive ticks was sequenced and compared to Borrelia sequences from GenBank. We estimated several population genetic measures to test the neutrality of the marker. We also assessed the ability of this marker to discriminate between Eurasian Borrelieae at a finer geographical resolution, and to detect population expansion per genospecies. Results: The most prevalent genospecies in The Netherlands was Borrelia afzelii, whereas Borrelia garinii, B. burgdorferi sensu stricto, Borrelia spielmanii and Borrelia valaisiana were found less frequently. The result of the Ewens-Watterson-Slatkin test was consistent with neutral selection of IGS region. Estimated pairwise fixation indices (Fst) were significantly different from zero between The Netherlands, the rest of Europe, Russia and Asia for B. afzelii and Borrelia garinii. Estimated Fu's Fs were significantly negative for B. afzelii and B. garinii. Conclusions: At least seven B. burgdorferi s.l. genospecies circulate in Ixodes ricinus population in The Netherlands. The population genetic analyses of IGS region can resolve subpopulations within a genospecies and detect a large excess of rare genetic variants at the genospecies level. A genetic trace of population expansion for B. afzelii and B. garinii is consistent with the reported increase in Lyme borreliosis incidence in European countries.
    Spatiotemporal dynamics of emerging pathogens in questing Ixodes ricinus
    Coipan, E.C. ; Jahfari, S. ; Fonville, M. ; Maassen, C.B. ; Giessen, J. van der; Takken, W. ; Takumi, K. ; Sprong, H. - \ 2013
    Frontiers in Cellular and Infection Microbiology 3 (2013). - ISSN 2235-2988 - 11 p.
    burgdorferi sensu-lato - geographic information-systems - human granulocytic ehrlichiosis - tick-borne diseases - borrelia-burgdorferi - anaplasma-phagocytophilum - lyme borreliosis - human babesiosis - europe - switzerland
    Ixodes ricinus transmits Borrelia burgdorferi sensu lato, the etiological agent of Lyme disease. Previous studies have also detected Rickettsia helvetica, Anaplasma phagocytophilum, Neoehrlichia mikurensis, and several Babesia species in questing ticks in The Netherlands. In this study, we assessed the acarological risk of exposure to several tick-borne pathogens (TBPs), in The Netherlands. Questing ticks were collected monthly between 2006 and 2010 at 21 sites and between 2000 and 2009 at one other site. Nymphs and adults were analysed individually for the presence of TBPs using an array-approach. Collated data of this and previous studies were used to generate, for each pathogen, a presence/absence map and to further analyse their spatiotemporal variation. R. helvetica (31.1%) and B. burgdorferi sensu lato (11.8%) had the highest overall prevalence and were detected in all areas. N. mikurensis (5.6%), A. phagocytophilum (0.8%), and Babesia spp. (1.7%) were detected in most, but not all areas. The prevalences of pathogens varied among the study areas from 0 to 64%, while the density of questing ticks varied from 1 to 179/100 m². Overall, 37% of the ticks were infected with at least one pathogen and 6.3% with more than one pathogen. One-third of the Borrelia-positive ticks were infected with at least one other pathogen. Coinfection of B. afzelii with N. mikurensis and with Babesia spp. occurred significantly more often than single infections, indicating the existence of mutual reservoir hosts. Alternatively, coinfection of R. helvetica with either B. afzelii or N. mikurensis occurred significantly less frequent. The diversity of TBPs detected in I. ricinus in this study and the frequency of their coinfections with B. burgdorferi s.l., underline the need to consider them when evaluating the risks of infection and subsequently the risk of disease following a tick bite.
    Brucella ceti in Harbour porpoises (Phocoena phocoena) from the Netherlands
    Begeman, L. ; Bisselink, Y.J.W.M. ; Giessen, J. van der; Hiemstra, S.J. ; Maio, E. ; Roest, H.I.J. ; Ruuls, R.C. ; Tulden, P.W. van; Wiersma, L. ; Gröne, A. - \ 2013
    Increasing prevalence and diversity of ESBL/AmpC-type ß-lactamase genes in Escherichia coli isolated from veal calves from 1997 to 2010
    Hordijk, J. ; Wagenaar, J.A. ; Giessen, A. van de; Dierikx, C.M. ; Essen-Zandbergen, A. van; Veldman, K. ; Kant, A. ; Mevius, D.J. - \ 2013
    Journal of Antimicrobial Chemotherapy 68 (2013)9. - ISSN 0305-7453 - p. 1970 - 1973.
    food-producing animals - extended-spectrum - companion animals - ampc - resistant - livestock - meat
    OBJECTIVES: Several studies on faecal carriage of extended-spectrum ß-lactamase (ESBL)/AmpC-producing Escherichia coli have been performed in cattle, but little is known about faecal carriage in veal calves. This study describes the prevalence and molecular characteristics of ESBL/AmpC genes in E. coli isolated from faecal samples of veal calves from 1997 to 2010. METHODS: Pooled faecal samples were inoculated using selective enrichment broth and subsequently selective MacConkey agar. All isolates with reduced susceptibility to cefotaxime were screened by PCR and sequencing analysis for the presence of ESBL/AmpC genes. RESULTS: The prevalence of E. coli with reduced susceptibility to cefotaxime showed a discontinuous increasing trend, ranging from 4% in 1998 and 1999 to 39% in 2010. Promoter mutations of the chromosomal ampC gene were present in all years. In 2000, ESBL genes blaCTX-M-1, blaTEM-52 and blaTEM-20 were first observed. Before 2005 the majority of E. coli with reduced susceptibility to cefotaxime harboured ampC promoter mutations. From 2005 onwards the majority harboured blaCTX-M genes, of which blaCTX-M-1 was the most abundant, followed by blaCTX-M-14 and blaCTX-M-15. The diversity of blaCTX-M genes gradually increased from one variant in 2000 to six variants in 2010. The prevalence of blaTEM-52 was relatively low, but it was detected from 2000 onwards. blaCMY and blaSHV were found sporadically. CONCLUSIONS: The prevalence and molecular diversity of genes encoding cefotaxime resistance in E. coli isolated from veal calves over a 14 year period showed an increasing trend. From 2005 onwards, blaCTX-M genes were most abundant, especially blaCTX-M-1.
    Development of a challenge model for Toxoplansma gondii in cats: assessment of a dose-response for infection
    Wisselink, H.J. ; Cornelissen, J.B.W.J. ; Teunis, P.F.M. ; Takumi, K. ; Giessen, J.W.B. van der - \ 2013
    In: Abstract Book of Med-Vet-Net Association International Scientific Conference DTU, Lyngby, Denmark, 24-25 June 2013. - - p. 34 - 34.
    Framing the tiger — A biodiversity concern in national and international media reporting
    Sadath, N. ; Kleinschmit, D. ; Giessen, L. - \ 2013
    Forest Policy and Economics 36 (2013). - ISSN 1389-9341 - p. 37 - 41.
    conservation
    International forest and environmental governance processes assume that ideas and concepts surrounding biodiversity at the international level will be made accessible at a national level so that they can be easily adopted by national forest and environmental policy arenas. One prerequisite for a seamless implementation of these ideas and concepts is a common definition of specific problems at different political levels. Different perceptions mirrored by media reporting on problems at different political levels may affect the implementation of policies thatmust be carried out at a national level, even if decisions concerning this implementation are made at an international level. Using the illustrative case of human–tiger interaction, this article shows how national and international media reporting differ in their framing of a particular problem. Based on a theoretical framework consisting framing and media selection theory, and on initial empirical observations, the article recommends blueprints for future in-depth research on the relationship between media framing and policy at different political levels. This case study is based on quantitative content analysis of reports on tiger–human interaction published between 2005 and 2010 in an international newspaper and a national one from Bangladesh. Our example shows that the selected national newspaper frames the tiger as a threat to the livelihood and well-being of local people, whereas the international newspaper stresses biodiversity and climate-change related aspects of human–tiger conflicts. These results indicate that the framing of an issue in the media can differ considerably at different levels and that this is a fruitful field for future in-depth research.
    Prevalence of livestock-associated MRSA on Dutch broiler farms and in people living and/or working on these farms
    Geenen, P.L. ; Graat, E.A.M. ; Haenen, A. ; Hengeveld, P.D. ; Hoek, A.H.A.M. van; Huijsdens, X.W. ; Kappert, C.C. ; Lammers, G.A.C. ; Duijkeren, E. van; Giessen, A.W. van de - \ 2013
    Epidemiology and Infection 141 (2013)5. - ISSN 0950-2688 - p. 1099 - 1108.
    resistant staphylococcus-aureus - pig farms - netherlands - poultry - admission - software - humans - origin - flocks - herds
    This study aimed to determine the prevalence and risk factors for methicillin-resistant Staphylococcus aureus (MRSA) on 50 Dutch broiler farms. Of 145 persons living and/or working on these farms, eight tested positive for MRSA (5.5%). Investigation of 250 pooled throat samples of broilers and 755 dust samples resulted in four farms where MRSA-positive samples were present (8.0%). All isolates belonged to the CC398 complex. Living and/or working on a MRSA-positive farm was a risk for MRSA carriage; 66.7% of people on positive farms were MRSA positive vs. 1.5% on negative farms (P
    Circumstantial evidence for an increase in the total number and activity of borrelia-infected ixodes ricinus in the Netherlands.
    Sprong, H. ; Hofhuis, A. ; Gassner, F. ; Takken, W. ; Jacobs, F. ; Vliet, A.J.H. van; Ballegooijen, M. van; Giessen, J. van der; Takumi, K. - \ 2012
    Parasites & Vectors 5 (2012)5. - ISSN 1756-3305 - 11 p.
    tick-borne diseases - burgdorferi sensu-lato - owls strix-aluco - lyme borreliosis - population-dynamics - ixodidae nymphs - endemic area - acari - ecology - risk
    BACKGROUND: Between 1994 and 2009, a threefold increase has been observed in consultations of general practitioners for tick bites and Lyme disease in The Netherlands. The objective of this study was to determine whether an increase in the number of questing ticks infected with B. burgdorferi sensu lato is a potential cause of the rise in Lyme disease incidence. METHODS: Historic data on land usage, temperature and wildlife populations were collected and analyzed together with data from two longitudinal field studies on density of questing ticks. Effective population sizes of Borrelia burgdorferi s.l. were calculated. RESULTS: Long-term trend analyses indicated that the length of the annual tick questing season increased as well as the surface area of tick-suitable habitats in The Netherlands. The overall abundances of feeding and reproductive hosts also increased. Mathematical analysis of the data from the field studies demonstrated an increase in mean densities/activities of questing ticks, particularly of larvae between 2006 and 2009. No increase in infection rate of ticks with Borrelia burgdorferi sensu lato was found. Population genetic analysis of the collected Borrelia species points to an increase in B. afzelii and B. garinii populations. CONCLUSIONS: Together, these findings indicate an increase in the total number of Borrelia-infected ticks, providing circumstantial evidence for an increase in the risk of acquiring a bite of a tick infected with B. burgdorferi s.l. Due to the high spatiotemporal variation of tick densities/activities, long-term longitudinal studies on population dynamics of I. ricinus are necessary to observe significant trends.
    Temporary governance and persistent government – Rural policy integration in pilot and mainstream funding programmes.
    Giessen, L. - \ 2012
    In: Environmental Governance: The Challenge of Legitimacy and Effectiveness / Hogl,, K., Kvarda,, E., Nordbeck,, R., Pregernig,, M., Chaltenham : Edward Elgar - ISBN 9781849806077 - p. 155 - 177.
    Description ‘This excellent collection of articles by leading scholars in a variety of natural resource policy fields examines cases in participation, horizontal and vertical co-ordination, and the role of science and expertise in environmental policy formation. The legitimacy and effectiveness of each of these key components of governance and meta-governance regimes is assessed in important areas such as climate change and parks and wilderness preservation. The volume brings an admirable consistency of focus to the analysis of new governance modes in environmental policy and sheds new light upon important recent trends and developments in the area.’ – Michael Howlett, Simon Fraser University, Canada.
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