• Accounting for ingrowth of radioactive progeny in dose assessments: generic weighting factors for dose coefficients.

      van Dillen, Teun; van Dijk, Arjan; Kloosterman, Astrid; Russo, Federica; Mommaert, Chantal (2019-08-27)
    • Accounting for long-term manifestations of Cryptosporidium spp infection in burden of disease and cost-of-illness estimations, the Netherlands (2013-2017).

      Monge, Susana; Pijnacker, Roan; van Pelt, Wilfrid; Franz, Eelco; Kortbeek, Laetitia M; Mangen, Marie-Josée J (2019-01-01)
      Burden of disease (BoD) estimations are increasingly used to prioritize public health interventions. Previous Cryptosporidium BoD models accounted only for acute episodes, while there is increasing evidence of long-term manifestations. Our objective was to update Cryptosporidium BoD and cost-of-illness (COI) models and to estimate BoD and COI for the Netherlands in years 2013-2017. We performed a scoping literature review and drew an outcome tree including long-term manifestations for which sufficient evidence was found, such as recurrent diarrhea and joint pain. We chose the Disability-Adjusted Life Year (DALY) metric to synthesize years of life lost due mortality (YLLs) and years lived with disability due to non-fatal outcomes (YLDs). For the costs, we adopted a societal perspective accounting for direct healthcare costs, patient costs and productivity losses. Uncertainty was managed using Latin Hypercube sampling (30,000 iterations). In the Netherlands in 2017, we estimated 50,000 Cryptosporidium cases (95% uncertainty interval (UI): 15,000-102,000), 7,000 GP visits, 300 hospitalizations and 3 deaths, resulting in 137 DALYs (95%UI: 54-255) and €19.2 million COI (95%UI: €7.2 million- €36.2 million). Estimates were highest for 2016 (218 DALYs and €31.1 million in COI), and lowest in 2013 (100 DALYs and €13.8 million in COI). Most of the BoD was attributable to YLD (≈80% of DALYs). The most important cost was productivity losses (≈90% of total COI). Long-term manifestations, including recurring diarrhea and joint pain, accounted for 9% of the total DALYs and 7% of the total COI. Current evidence supports the inclusion of long-term manifestations in Cryptosporidium models, which contribute close to 10% of the total DALYs and costs. This may be an underestimation, as we were conservative in our assumptions. Cryptosporidium should be considered a priority organism with respect to public health surveillance, even in industrialized countries with high hygiene standards.
    • Accurate Serology for SARS-CoV-2 and common Human Coronaviruses using a Multiplex Approach.

      van Tol, Sophie; Mögling, Ramona; Li, Wentao; Godeke, Gert-Jan; Swart, Arno; Bergmans, Barbara; Brandenburg, Afke; Kremer, Kristin; Murk, Jean-Luc; van Beek, Josine; et al. (2020-08-20)
    • Acellular Pertussis Vaccines Induce Anti-pertactin Bactericidal Antibodies Which Drives the Emergence of Pertactin-Negative Strains.

      Lesne, Elodie; Cavell, Breeze E; Freire-Martin, Irene; Persaud, Ruby; Alexander, Frances; Taylor, Stephen; Matheson, Mary; van Els, Cécile A C M; Gorringe, Andrew (2020-01-01)
      Despite high vaccination coverage, Bordetella pertussis the causative agent of whooping cough is still a health concern worldwide. A resurgence of pertussis cases has been reported, particularly in countries using acellular vaccines with waning immunity and pathogen adaptation thought to be responsible. A better understanding of protective immune responses is needed for the development of improved vaccines. In our study, B. pertussis strain B1917 variants presenting a single gene deletion were generated to analyze the role of vaccine components or candidate vaccine antigens as targets for bactericidal antibodies generated after acellular vaccination or natural infection. Our results show that acellular vaccination generates bactericidal antibodies that are only directed against pertactin. Serum bactericidal assay performed with convalescent samples show that disease induces bactericidal antibodies against Prn but against other antigen(s) as well. Four candidate vaccine antigens (CyaA, Vag8, BrkA, and TcfA) have been studied but were not targets for complement-mediated bactericidal antibodies after natural infection. We confirm that Vag8 and BrkA are involved in complement resistance and would be targeted by blocking antibodies. Our study suggests that the emergence and the widespread circulation of Prn-deficient strains is driven by acellular vaccination and the generation of bactericidal antibodies targeting Prn.
    • Achieving successful community engagement: a rapid realist review

      De Weger, E.; Van Vooren, N.; Luijkx, K. G.; Baan, C. A.; Drewes, H. W. (2018-04-13)
    • Acquisition of C1 inhibitor by Bordetella pertussis virulence associated gene 8 results in C2 and C4 consumption away from the bacterial surface.

      Hovingh, Elise S; van den Broek, Bryan; Kuipers, Betsy; Pinelli, Elena; Rooijakkers, Suzan H M; Jongerius, Ilse (2017-07)
      Whooping cough, or pertussis, is a contagious disease of the respiratory tract that is re-emerging worldwide despite high vaccination coverage. The causative agent of this disease is the Gram-negative Bordetella pertussis. Knowledge on complement evasion strategies of this pathogen is limited. However, this is of great importance for future vaccine development as it has become apparent that a novel pertussis vaccine is needed. Here, we unravel the effect of Virulence associated gene 8 (Vag8) of B. pertussis on the human complement system at the molecular level. We show that both recombinant and endogenously secreted Vag8 inhibit complement deposition on the bacterial surface at the level of C4b. We reveal that Vag8 binding to human C1-inhibitor (C1-inh) interferes with the binding of C1-inh to C1s, C1r and MASP-2, resulting in the release of active proteases that subsequently cleave C2 and C4 away from the bacterial surface. We demonstrate that the depletion of these complement components in the bacterial surrounding and subsequent decreased deposition on B. pertussis leads to less complement-mediated bacterial killing. Vag8 is the first protein described that specifically prevents C1s, C1r and MASP-2 binding to C1-inh and thereby mediates complement consumption away from the bacterial surface. Unravelling the mechanism of this unique complement evasion strategy of B. pertussis is one of the first steps towards understanding the interactions between the first line of defense complement and B. pertussis.
    • Acquisition of multidrug-resistant Enterobacterales during international travel: a systematic review of clinical and microbiological characteristics and meta-analyses of risk factors.

      Voor In 't Holt, Anne F; Mourik, Kees; Beishuizen, Berend; van der Schoor, Adriënne S; Verbon, Annelies; Vos, Margreet C; Severin, Juliëtte A (2020-05-20)
    • Acquisition of wild-type HIV-1 infection in a patient on pre-exposure prophylaxis with high intracellular concentrations of tenofovir diphosphate: a case report.

      Hoornenborg, Elske; Prins, Maria; Achterbergh, Roel C A; Woittiez, Lycke R; Cornelissen, Marion; Jurriaans, Suzanne; Kootstra, Neeltje A; Anderson, Peter L; Reiss, Peter; de Vries, Henry J C; et al. (2017-11)
      Pre-exposure prophylaxis (PrEP) with emtricitabine and tenofovir disoproxil fumarate is highly effective against acquisition of HIV infection, and only two cases of infection with a multidrug-resistant virus have been reported under adequate long-term adherence, as evidenced by tenofovir diphosphate concentrations in dried blood spots. We report a case of wild-type HIV-1 infection despite consistent use of emtricitabine and tenofovir disoproxil fumarate.
    • An across-species comparison of the sensitivity of different organisms to Pb-based perovskites used in solar cells.

      Wang, Guiyin; Zhai, Yujia; Zhang, Shirong; Diomede, Luisa; Bigini, Paolo; Romeo, Margherita; Cambier, Sebastien; Contal, Servane; Nguyen, Nhung H A; Rosická, Petra; et al. (2020-03-15)
      Organic-inorganic perovskite solar cells (PSCs) are promising candidates as photovoltaic cells. Recently, they have attracted significant attention due to certified power conversion efficiencies exceeding 23%, low-cost engineering, and superior electrical/optical characteristics. These PSCs extensively utilize a perovskite-structured composite with a hybrid of Pb-based nanomaterials. Operation of them may cause the release of Pb-based nanoparticles. However, limited information is available regarding the potential toxicity of Pb-based PSCs on various organisms. This study conducted a battery of in vitro and in vivo toxicity bioassays for three quintessential Pb-based PSCs (CH3NH3PbI3, NHCHNH3PbBr3, and CH3NH3PbBr3) using progressively more complex forms of life. For all species tested, the three different perovskites had comparable toxicities. The viability of Caco-2/TC7 cells was lower than that of A549 cells in response to Pb-based PSC exposure. Concentration-dependent toxicity was observed for the bioluminescent bacterium Vibrio fischeri, for soil bacterial communities, and for the nematode Caenorhabditis elegans. Neither of the tested Pb-based PSCs particles had apparent toxicity to Pseudomonas putida. Among all tested organisms, V. fischeri showed the highest sensitivity with EC50 values (30 min of exposure) ranging from 1.45 to 2.91 mg L-1. Therefore, this study recommends that V. fischeri should be preferably utilized to assess. PSC toxicity due to its increased sensitivity, low costs, and relatively high throughput in a 96-well format, compared with the other tested organisms. These results highlight that the developed assay can easily predict the toxic potency of PSCs. Consequently, this approach has the potential to promote the implementation of the 3Rs (Replacement, Reduction, and Refinement) principle in toxicology and decrease the dependence on animal testing when determining the safety of novel PSCs.
    • Activation of Human Monocytes by Colloidal Aluminum Salts.

      Vrieling, Hilde; Kooijman, Sietske; de Ridder, Justin W; Thies-Weesie, Dominique M E; Soema, Peter C; Jiskoot, Wim; van Riet, Elly; Heck, Albert J R; Philipse, Albert P; Kersten, Gideon F A; et al. (2019-08-23)
    • Activation of Human NK Cells by Requires Inflammasome Activation in Macrophages.

      Kroes, Michiel M; Mariman, Rob; Hijdra, Daniëlle; Hamstra, Hendrik-Jan; van Boxtel, Karlijn J W M; van Putten, Jos P M; de Wit, Jelle; Pinelli, Elena (2019-01-01)
      Pertussis is a highly contagious respiratory infection caused by the bacterium Bordetella pertussis. Humans are the only known natural reservoir of B. pertussis. In mice, macrophages and NK cells have a key role in confining B. pertussis to the respiratory tract. However, the mechanisms underlying this process, particularly during human infections, remain unclear. Here we characterized the activation of human macrophages and NK cells in response to B. pertussis and unraveled the role of inflammasomes in this process. NLRP3 inflammasome activation by B. pertussis in human macrophage-like THP-1 cells and primary monocyte-derived macrophages (mo-MΦ) was shown by the visualization of ASC-speck formation, pyroptosis, and the secretion of caspase-mediated IL-1β and IL-18. In contrast to macrophages, stimulation of human CD56+CD3- NK cells by B. pertussis alone did not result in activation of these cells. However, co-culture of B. pertussis-stimulated mo-MΦ and autologous NK cells resulted in high amounts of IFNγ secretion and an increased frequency of IL-2Rα+ and HLA-DR+ NK cells, indicating NK cell activation. This activation was significantly reduced upon inhibition of inflammasome activity or blocking of IL-18 in the mo-MΦ/NK cell co-culture. Furthermore, we observed increased secretion of proinflammatory cytokines in the B. pertussis-stimulated mo-MΦ/NK co-culture compared to the mo-MΦ single culture. Our results demonstrate that B. pertussis induces inflammasome activation in human macrophages and that the IL-18 produced by these cells is required for the activation of human NK cells, which in turn enhances the pro-inflammatory response to this pathogen. Our data provides a better understanding of the underlying mechanisms involved in the induction of innate immune responses against B. pertussis. These findings contribute to the knowledge required for the development of improved intervention strategies to control this highly contagious disease.
    • Active case finding and treatment adherence in risk groups in the tuberculosis pre-elimination era.

      Gupta, R K; Lipman, M; Story, A; Hayward, A; de Vries, G; van Hest, R; Erkens, C; Rangaka, M X; Abubakar, I (2018-05-01)
      Vulnerable populations, including homeless persons, high-risk drug and alcohol users, prison inmates and other marginalised populations, contribute a disproportionate burden of tuberculosis (TB) cases in low-incidence settings. Drivers of this disease burden include an increased risk of both TB transmission in congregate settings, and progression from infection to active disease. Late diagnosis and poor treatment completion further propagate the epidemic and fuel the acquisition of drug resistance. These groups are therefore a major priority for TB control programmes in low-incidence settings. Targeted strategies include active case finding (ACF) initiatives and interventions to improve treatment completion, both of which should be tailored to local populations. ACF usually deploys mobile X-ray unit screening, which allows sensitive, high-throughput screening with immediate availability of results. Such initiatives have been found to be effective and cost-effective, and associated with reductions in proxy measures of transmission in hard-to-reach groups. The addition of point-of-care molecular diagnostics and automated X-ray readers may further streamline the screening pathway. There is little evidence to support interventions to improve adherence among these risk groups. Such approaches include enhanced case management and directly observed treatment, while video-observed therapy (currently under evaluation) appears to be a promising tool for the future. Integrating outreach services to include both case detection and case-management interventions that share a resource infrastructure may allow cost-effectiveness to be maximised. Integrating screening and treatment for other diseases that are prevalent among targeted risk groups into TB outreach interventions may further improve cost-effectiveness. This article reviews the existing literature, and highlights priorities for further research.
    • Active commuting through natural environments is associated with better mental health: Results from the PHENOTYPE project.

      Zijlema, Wilma L; Avila-Palencia, Ione; Triguero-Mas, Margarita; Gidlow, Christopher; Maas, Jolanda; Kruize, Hanneke; Andrusaityte, Sandra; Grazuleviciene, Regina; Nieuwenhuijsen, Mark J (2018-12)
      Commuting routes with natural features could promote walking or cycling for commuting. Commuting through natural environments (NE) could have mental health benefits as exposure to NE can reduce stress and improve mental health, but there is little evidence. This study evaluates the association between NE and commuting, whether active or not, and the association between commuting (through NE), whether active or not, and mental health. We also evaluate the moderating effect of NE quality on the association between NE commuting and mental health.
    • Acute Gastroenteritis Disease Burden in Infants With Medical Risk Conditions in the Netherlands.

      van Dongen, Josephine A P; Rouers, Elsbeth D M; Schuurman, Rob; Bonten, Marc J M; Bruijning-Verhagen, Patricia (2020-11-18)
    • Acute hepatitis C infection among adults with HIV in the Netherlands between 2003 and 2016: a capture-recapture analysis for the 2013 to 2016 period.

      Boender, T Sonia; Op de Coul, Eline; Arends, Joop; Prins, Maria; van der Valk, Marc; van der Meer, Jan T M; van Benthem, Birgit; Reiss, Peter; Smit, Colette (2020-02-01)
    • Acute illness from Campylobacter jejuni may require high doses while infection occurs at low doses.

      Teunis, Peter F M; Bonačić Marinović, Axel; Tribble, David R; Porter, Chad K; Swart, Arno (2018-02-08)
      Data from a set of different studies on the infectivity and pathogenicity of Campylobacter jejuni were analyzed with a multilevel model, allowing for effects of host species (nonhuman primates and humans) and different strains of the pathogen. All challenge studies involved high doses of the pathogen, resulting in all exposed subjects to become infected. In only one study a dose response effect (increasing trend with dose) for infection was observed. High susceptibility to infection with C. jejuni was found in a joint analysis of outbreaks and challenge studies. For that reason four outbreaks, associated with raw milk consumption, were also included in the present study. The high doses used for inoculation did not cause all infected subjects to develop acute enteric symptoms. The observed outcomes are consistent with a dose response effect for acute symptoms among infected subjects: a conditional illness dose response relation. Nonhuman primates and human volunteers did not appear to have different susceptibilities for developing enteric symptoms, but exposure in outbreaks (raw milk) did lead to a higher probability of symptomatic campylobacteriosis.
    • Acute Otitis Media During Infancy: Parent-reported Incidence and Modifiable Risk Factors.

      Prins-van Ginkel, Annemarijn C; Bruijning-Verhagen, Patricia C J; Uiterwaal, Cuno S P M; van der Ent, Cornelis K; Smit, Henriette A; de Hoog, Marieke L A (2017-03)
      Age at exposure to acute otitis media (AOM) risk factors such as day care attendance, lack of breastfeeding and tobacco smoke is little studied but important for targeting AOM prevention strategies. Moreover, studies are typically restricted to clinically diagnosed AOM, while a significant subset can occur outside the health care system, depending on the country setting. This study aims to determine risk factor exposure and effect of its timing within the first year of life on parent-reported AOM symptom episodes.
    • Adaptation of Bordetella pertussis to the respiratory tract.

      van Beek, Lucille L F; de Gouw, Daan D; Eleveld, Marc M J; Bootsma, Hester H J; de Jonge, Marien M I; Mooi, Frits F R; Zomer, Aldert A; Diavatopoulos, Dimitri D A (2018-03-08)
      There is a lack of insight into the basic mechanisms by which Bordetella pertussis adapts to the local host environment during infection. We analysed B. pertussis gene expression in the upper and lower airways of mice and compared this to SO4-induced in vitro Bvg-regulated gene transcription. Approximately 30% of all genes were found to be differentially expressed between in vitro vs. in vivo conditions. This included several novel potential vaccine antigens that were exclusively expressed in vivo. Significant differences in expression profile and metabolic pathways were identified between the upper versus the lower airways, suggesting distinct antigenic profiles. We found high expression of several Bvg-repressed genes during infection and mouse vaccination experiments using purified protein fractions from both Bvg- and Bvg+ cultures demonstrated protection against intranasal B. pertussis challenge. This study provides novel insights into the in vivo adaptation of B. pertussis and may facilitate the improvement of pertussis vaccines.
    • Adapting Citizen Science to Improve Health in an Occupational Setting: Preliminary Results of a Qualitative Study.

      van den Berge, Mandy; Hulsegge, Gerben; van der Molen, Henk F; Proper, Karin I; Pasman, H Roeline W; den Broeder, Lea; Tamminga, Sietske J; Hulshof, Carel T J; van der Beek, Allard J (2020-07-08)