• Erysipeloïd na contact met geïnfecteerd pluimvee

      Kense, Merlijn; Fanoy, Ewout; Maas, Jaap; Wittgen, Steven; Notermans, Daan (2018-02-15)
    • ESAT-6 and CFP-10 in clinical versus environmental isolates of Mycobacterium kansasii.

      Arend, Sandra M; Haas, Petra de; Leyten, Eliane; Rosenkrands, Ida; Rigouts, Leen; Andersen, Peter; Mijs, Wouter; Dissel, Jaap T van; Soolingen, Dick van (2005-04-15)
      Mycobacterium kansasii consists of 5 genetically distinct groups, of which 2 are associated with human disease. Determinants of the differences in virulence are unknown. Potential genes of interest are esat-6 and cfp-10, which are associated with virulence of Mycobacterium tuberculosis and Mycobacterium bovis but are lacking in bacille Calmette-Guérin and in most environmental mycobacteria (M. kansasii is an exception). We investigated esat-6 and cfp-10 genes in 22 clinical and 14 environmental isolates of M. kansasii. Both were present in all isolates; each genetic group had its own characteristic Southern-blot pattern corresponding to a highly conserved fingerprint pattern. Nucleotide sequences of the genes differed 12.6% and 10.1%, respectively, from the M. tuberculosis homologues, but the deduced amino acid sequences were <5% different. In vitro, clinical and environmental genotypes of M. kansasii expressed CFP-10 and ESAT-6. Thus, virulence of M. kansasii is not directly related to esat-6 and cfp-10 genes or gene expression.
    • Establishment of a genotyping scheme for Coxiella burnetii.

      Svraka, Sanela; Toman, Rudolf; Skultety, Ludovit; Slaba, Katarina; Homan, Wieger L (2006-01-01)
      Coxiella burnetii is the causative agent of Q fever. The bacterium is highly infectious and is classified as a category B biological weapon. The tools of molecular biology are of utmost importance in a rapid and unambiguous identification of C. burnetii in naturally occurring Q fever outbreaks, or in cases of a deliberate release of the infectious agent. In this work, development of a multiple locus variable number tandem repeats (VNTR) analysis (MLVA) for the characterization of C. burnetii is described. Sixteen C. burnetii isolates and five passage history/laboratory variants were characterized. The VNTR markers revealed many polymorphisms resulting in nine unique MLVA types that cluster into five different clusters. This proves that the MLVA system is highly discriminatory. The selected VNTR markers were stable. The MLVA method developed in this report is a promising tool for the characterization of C. burnetii isolates and their epidemiological study.
    • Establishment of a National Inventory of Dangerous Pathogens in the Republic of Uganda.

      Brizee, Sabrina; Kwehangana, Musa; Mwesigwa, Collins; Bleijs, Diederik A; van den Berg, Harold H J L; Kampert, Evelien; Makoba, Milton Wetaka; Kagirita, Atek; Makumbi, Issa; Kakooza, Francis; et al.
    • Estimated incidence and number of outpatient visits for seasonal influenza in 2015-2016 in Beijing, China.

      Wu, S; Van Asten, L; Wang, L; McDonald, S A; Pan, Y; Duan, W; Zhang, L; Sun, Y; Zhang, Y; Zhang, X; et al. (2017)
      Information on morbidity burden of seasonal influenza in China is limited. A multiplier model was used to estimate the incidence and number of outpatient visits for seasonal influenza by age group for the 2015-2016 season in Beijing, the capital of China, based on reported numbers of influenza-like illness consultations and proportions of positive cases from influenza surveillance systems in Beijing, general consultation rates and other parameters from previous studies, surveys and surveillance systems. An estimated total of 1 190 200 (95% confidence interval (CI) 830 400-1 549 900) cases of influenza virus infections occurred in Beijing, 2015-2016 season, with an attack rate of 5·5% (95% CI 3·9-7·2%). These infections resulted in an estimated 468 280 (95% CI 70 700-606 800) outpatient visits, with an attack rate of 2·2% (95% CI 0·3-2·8%). The attack rate of influenza virus infections was highest among children aged 0-4 years (31·9% (95% CI 21·9-41·9%)), followed by children aged 5-14 years (18·7% (95% CI 12·9-24·5%)). Our study demonstrated a substantial influenza-related morbidity in Beijing, China, especially among the preschool- and school-aged children. This suggests that development or modification of seasonal influenza targeted vaccination strategies need to recognize that incidence is highest in children.
    • Estimated Substitution of Tea or Coffee for Sugar-Sweetened Beverages Was Associated with Lower Type 2 Diabetes Incidence in Case-Cohort Analysis across 8 European Countries in the EPIC-InterAct Study.

      Imamura, Fumiaki; Schulze, Matthias B; Sharp, Stephen J; Guevara, Marcela; Romaguera, Dora; Bendinelli, Benedetta; Salamanca-Fernández, Elena; Ardanaz, Eva; Arriola, Larraitz; Aune, Dagfinn; et al. (2019-08-08)
    • Estimates of global seasonal influenza-associated respiratory mortality: a modelling study.

      Iuliano, A Danielle; Roguski, Katherine M; Chang, Howard H; Muscatello, David J; Palekar, Rakhee; Tempia, Stefano; Cohen, Cheryl; Gran, Jon Michael; Schanzer, Dena; Cowling, Benjamin J; et al. (2017-12-14)
      Estimates of influenza-associated mortality are important for national and international decision making on public health priorities. Previous estimates of 250 000-500 000 annual influenza deaths are outdated. We updated the estimated number of global annual influenza-associated respiratory deaths using country-specific influenza-associated excess respiratory mortality estimates from 1999-2015.
    • Estimating disease prevalence from drug utilization data using the Random Forest algorithm.

      Slobbe, Laurentius C J; Füssenich, Koen; Wong, Albert; Boshuizen, Hendriek C; Nielen, Markus M J; Polder, Johan J; Feenstra, Talitha L; van Oers, Hans A M (2019-01-03)
      Aggregated claims data on medication are often used as a proxy for the prevalence of diseases, especially chronic diseases. However, linkage between medication and diagnosis tend to be theory based and not very precise. Modelling disease probability at an individual level using individual level data may yield more accurate results. Individual probabilities of having a certain chronic disease were estimated using the Random Forest (RF) algorithm. A training set was created from a general practitioners database of 276 723 cases that included diagnosis and claims data on medication. Model performance for 29 chronic diseases was evaluated using Receiver-Operator Curves, by measuring the Area Under the Curve (AUC). The diseases for which model performance was best were Parkinson's disease (AUC = .89, 95% CI = .77-1.00), diabetes (AUC = .87, 95% CI = .85-.90), osteoporosis (AUC = .87, 95% CI = .81-.92) and heart failure (AUC = .81, 95% CI = .74-.88). Five other diseases had an AUC >.75: asthma, chronic enteritis, COPD, epilepsy and HIV/AIDS. For 16 of 17 diseases tested, the medication categories used in theory-based algorithms were also identified by our method, however the RF models included a broader range of medications as important predictors. Data on medication use can be a useful predictor when estimating the prevalence of several chronic diseases. To improve the estimates, for a broader range of chronic diseases, research should use better training data, include more details concerning dosages and duration of prescriptions, and add related predictors like hospitalizations.
    • Estimating health-adjusted life expectancy conditional on risk factors: results for smoking and obesity.

      Baal, Pieter H M van; Hoogenveen, Rudolf T; Wit, G Ardine de; Boshuizen, Hendriek C (2006)
      ABSTRACT: BACKGROUND: Smoking and obesity are risk factors causing a large burden of disease. To help formulate and prioritize among smoking and obesity prevention activities, estimations of health-adjusted life expectancy (HALE) for cohorts that differ solely in their lifestyle (e.g. smoking vs. non smoking) can provide valuable information. Furthermore, in combination with estimates of life expectancy (LE), it can be tested whether prevention of obesity and smoking results in compression of morbidity. METHODS: Using a dynamic population model that calculates the incidence of chronic disease conditional on epidemiological risk factors, we estimated LE and HALE at age 20 for a cohort of smokers with a normal weight (BMI < 25), a cohort of non-smoking obese people (BMI>30) and a cohort of 'healthy living' people (i.e. non smoking with a BMI < 25). Health state valuations for the different cohorts were calculated using the estimated disease prevalence rates in combination with data from the Dutch Burden of Disease study. Health state valuations are multiplied with life years to estimate HALE. Absolute compression of morbidity is defined as a reduction in unhealthy life expectancy (LE-HALE) and relative compression as a reduction in the proportion of life lived in good health (LE-HALE)/LE. RESULTS: Estimates of HALE are highest for a 'healthy living' cohort (54.8 years for men and 55.4 years for women at age 20). Differences in HALE compared to 'healthy living' men at age 20 are 7.8 and 4.6 for respectively smoking and obese men. Differences in HALE compared to 'healthy living' women at age 20 are 6.0 and 4.5 for respectively smoking and obese women. Unhealthy life expectancy is about equal for all cohorts, meaning that successful prevention would not result in absolute compression of morbidity. Sensitivity analyses demonstrate that although estimates of LE and HALE are sensitive to changes in disease epidemiology, differences in LE and HALE between the different cohorts are fairly robust. In most cases, elimination of smoking or obesity does not result in absolute compression of morbidity but slightly increases the part of life lived in good health. CONCLUSION: Differences in HALE between smoking, obese and 'healthy living' cohorts are substantial and similar to differences in LE. However, our results do not indicate that substantial compression of morbidity is to be expected as a result of successful smoking or obesity prevention.
    • Estimating incidence and prevalence rates of chronic diseases using disease modeling.

      Boshuizen, Hendrike C; Poos, Marinus J J C; van den Akker, Marjan; van Boven, Kees; Korevaar, Joke C; de Waal, Margot W M; Biermans, Marion C J; Hoeymans, Nancy (2017-04-05)
      Morbidity estimates between different GP registration networks show large, unexplained variations. This research explores the potential of modeling differences between networks in distinguishing new (incident) cases from existing (prevalent) cases in obtaining more reliable estimates.
    • Estimating severity of influenza epidemics from severe acute respiratory infections (SARI) in intensive care units.

      van Asten, Liselotte; Luna Pinzon, Angie; de Lange, Dylan W; de Jonge, Evert; Dijkstra, Frederika; Marbus, Sierk; Donker, Gé A; van der Hoek, Wim; de Keizer, Nicolette F (2018-12-19)
      While influenza-like-illness (ILI) surveillance is well-organized at primary care level in Europe, few data are available on more severe cases. With retrospective data from intensive care units (ICU) we aim to fill this current knowledge gap. Using multiple parameters proposed by the World Health Organization we estimate the burden of severe acute respiratory infections (SARI) in the ICU and how this varies between influenza epidemics. We analyzed weekly ICU admissions in the Netherlands (2007-2016) from the National Intensive Care Evaluation (NICE) quality registry (100% coverage of adult ICUs in 2016; population size 14 million) to calculate SARI incidence, SARI peak levels, ICU SARI mortality, SARI mean Acute Physiology and Chronic Health Evaluation (APACHE) IV score, and the ICU SARI/ILI ratio. These parameters were calculated both yearly and per separate influenza epidemic (defined epidemic weeks). A SARI syndrome was defined as admission diagnosis being any of six pneumonia or pulmonary sepsis codes in the APACHE IV prognostic model. Influenza epidemic periods were retrieved from primary care sentinel influenza surveillance data. Annually, an average of 13% of medical admissions to adult ICUs were for a SARI but varied widely between weeks (minimum 5% to maximum 25% per week). Admissions for bacterial pneumonia (59%) and pulmonary sepsis (25%) contributed most to ICU SARI. Between the eight different influenza epidemics under study, the value of each of the severity parameters varied. Per parameter the minimum and maximum of those eight values were as follows: ICU SARI incidence 558-2400 cumulated admissions nationwide, rate 0.40-1.71/10,000 inhabitants; average APACHE score 71-78; ICU SARI mortality 13-20%; ICU SARI/ILI ratio 8-17 cases per 1000 expected medically attended ILI in primary care); peak-incidence 101-188 ICU SARI admissions in highest-incidence week, rate 0.07-0.13/10,000 population). In the ICU there is great variation between the yearly influenza epidemic periods in terms of different influenza severity parameters. The parameters also complement each other by reflecting different aspects of severity. Prospective syndromic ICU SARI surveillance, as proposed by the World Health Organization, thereby would provide insight into the severity of ongoing influenza epidemics, which differ from season to season.
    • Estimating the Human Papillomavirus Genotype Attribution in Screen-detected High-grade Cervical Lesions.

      Lissenberg-Witte, Birgit I; Bogaards, Johannes A; Quint, Wim G V; Berkhof, Johannes (2019-07-01)
    • Estimating the Impact of High-Production-Volume Chemicals on Remote Ecosystems by Toxic Pressure Calculation

      Harbers, Jasper V; Huijbregts, Mark A J; Posthuma, Leo; Meent, Dik van de (2006-01-14)
      Although many chemicals are in use, the environmental impacts of only a few have been established, usually on per-chemical basis. Uncertainty remains about the overall impact of chemicals. This paper estimates combined toxic pressure on coastal North Sea ecosystems from 343 high-production-volume chemicals used within the catchment of rivers Rhine, Meuse, and Scheldt. Multimedia fate modeling and species sensitivity distribution-based effects estimation are applied. Calculations start from production volumes and emission rates and use physicochemical substance properties and aquatic ecotoxicity data. Parameter uncertainty is addressed by Monte Carlo simulations. Results suggest that the procedure is technically feasible. Combined toxic pressure of all 343 chemicals in coastal North Seawater is 0.025 (2.5% of the species are exposed to concentration levels above EC50 values), with a wide confidence interval of nearly 0-1. This uncertainty appears to be largely due to uncertainties in interspecies variances of aquatic toxicities and, to a lesser extent, to uncertainties in emissions and degradation rates. Due to these uncertainties, the results support gross ranking of chemicals in categories: negligible and possibly relevant contributions only. With 95% confidence, 283 of the 343 chemicals (83%) contribute negligibly (less than 0.1%) to overall toxic pressure, and only 60 (17%) need further consideration.
    • Estimating the Population-Level Effectiveness of Vaccination Programs in the Netherlands.

      van Wijhe, Maarten; McDonald, Scott A; de Melker, Hester E; Postma, Maarten J; Wallinga, Jacco (2018-03)
      There are few estimates of the effectiveness of long-standing vaccination programs in developed countries. To fill this gap, we investigate the direct and indirect effectiveness of childhood vaccination programs on mortality at the population level in the Netherlands.
    • Estimating the prevalence of 26 health-related indicators at neighbourhood level in the Netherlands using structured additive regression.

      van de Kassteele, Jan; Zwakhals, Laurens; Breugelmans, Oscar; Ameling, Caroline; van den Brink, Carolien (2017-07-01)
      Local policy makers increasingly need information on health-related indicators at smaller geographic levels like districts or neighbourhoods. Although more large data sources have become available, direct estimates of the prevalence of a health-related indicator cannot be produced for neighbourhoods for which only small samples or no samples are available. Small area estimation provides a solution, but unit-level models for binary-valued outcomes that can handle both non-linear effects of the predictors and spatially correlated random effects in a unified framework are rarely encountered.
    • Estimating the scale of chronic hepatitis B virus infection among migrants in EU/EEA countries.

      Ahmad, Amena A; Falla, Abby M; Duffell, Erika; Noori, Teymur; Bechini, Angela; Reintjes, Ralf; Veldhuijzen, Irene K (2018-01-11)
    • Estimating the scale of chronic hepatitis C virus infection in the EU/EEA: a focus on migrants from anti-HCV endemic countries.

      Falla, A M; Ahmad, A A; Duffell, E; Noori, T; Veldhuijzen, I K (2018-01-16)
      Increasing the proportion diagnosed with and on treatment for chronic hepatitis C (CHC) is key to the elimination of hepatitis C in Europe. This study contributes to secondary prevention planning in the European Union/European Economic Area (EU/EEA) by estimating the number of CHC (anti-HCV positive and viraemic) cases among migrants living in the EU/EEA and born in endemic countries, defining the most affected migrant populations, and assessing whether country of birth prevalence is a reliable proxy for migrant prevalence.
    • Estimation of age-specific rates of reactivation and immune boosting of the varicella zoster virus.

      Marinelli, Isabella; van Lier, Alies; de Melker, Hester; Pugliese, Andrea; van Boven, Michiel (2017)
      Studies into the impact of vaccination against the varicella zoster virus (VZV) have increasingly focused on herpes zoster (HZ), which is believed to be increasing in vaccinated populations with decreasing infection pressure. This idea can be traced back to Hope-Simpson's hypothesis, in which a person's immune status determines the likelihood that he/she will develop HZ. Immunity decreases over time, and can be boosted by contact with a person experiencing varicella (exogenous boosting) or by a reactivation attempt of the virus (endogenous boosting). Here we use transmission models to estimate age-specific rates of reactivation and immune boosting, exogenous as well as endogenous, using zoster incidence data from the Netherlands (2002-2011, n=7026). The boosting and reactivation rates are estimated with splines, enabling these quantities to be optimally informed by the data. The analyses show that models with high levels of exogenous boosting and estimated or zero endogenous boosting, constant rate of loss of immunity, and reactivation rate increasing with age (to more than 5% per year in the elderly) give the best fit to the data. Estimates of the rates of immune boosting and reactivation are strongly correlated. This has important implications as these parameters determine the fraction of the population with waned immunity. We conclude that independent evidence on rates of immune boosting and reactivation in persons with waned immunity are needed to robustly predict the impact of varicella vaccination on the incidence of HZ.
    • Ethanol Intake and Risk of Lung Cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC).

      Rohrmann, Sabine; Linseisen, Jakob; Boshuizen, Hendriek C; Whittaker, John; Agudo, Antonio; Vineis, Paolo; Boffetta, Paolo; Jensen, Majken K; Olsen, Anja; Overvad, Kim; et al. (2006-12-01)
      Within the European Prospective Investigation into Cancer and Nutrition (EPIC), the authors examined the association of ethanol intake at recruitment (1,119 cases) and mean lifelong ethanol intake (887 cases) with lung cancer. Information on baseline and past alcohol consumption, lifetime tobacco smoking, diet, and the anthropometric characteristics of 478,590 participants was collected between 1992 and 2000. Cox proportional hazards regression was used to calculate multivariate-adjusted hazard ratios and 95% confidence intervals. Overall, neither ethanol intake at recruitment nor mean lifelong ethanol intake was significantly associated with lung cancer. However, moderate intake (5-14.9 g/day) at recruitment (hazard ratio (HR) = 0.76, 95% confidence interval (CI): 0.63, 0.90) and moderate mean lifelong intake (HR = 0.80, 95% CI: 0.66, 0.97) were associated with a lower lung cancer risk in comparison with low consumption (0.1-4.9 g/day). Compared with low intake, a high (>/=60 g/day) mean lifelong ethanol intake tended to be related to a higher risk of lung cancer (HR = 1.29, 95% CI: 0.93, 1.74), but high intake at recruitment was not. Although there was no overall association between ethanol intake and risk of lung cancer, the authors cannot rule out a lower risk for moderate consumption and a possibly increased risk for high lifelong consumption.