Jaap ten Oever

Dr. Jaap ten Oever


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 April 2020 in Eurosurveillance
Verified
Journal Article
Open access
ATAlma Tostmann
Alma Tostmann
JBJohn Bradley
John Bradley
TBTeun Bousema
Teun Bousema
WYWing-Kee Yiek
Wing-Kee Yiek
MHMinke Holwerda
Minke Holwerda
HWHeiman Wertheim
Heiman Wertheim
Healthcare workers (n = 803) with mild symptoms were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (n = 90 positive) and asked to complete a symptom questionnaire. Anosmia, muscle ache, ocular pain, general malaise, headache, extreme tiredness and fever were associated with positivity. A predictive model based on these symptoms showed moderate discriminative value (sensitivity: 91.2%; specificity: 55.6%). While our models would not justify presumptive SARS-CoV-2 diagnosis without molecular confirmation, it can contribute to targeted screening strategies.

21 January 2020 in Microorganisms
Verified
Journal Article
Open access
PDF file
DRDiletta Rosati
Diletta Rosati
MBMariolina Bruno
Mariolina Bruno
MJmartin Jaeger
martin Jaeger
JOJaap ten Oever
Jaap ten Oever
MNMihai G. Netea
Mihai G. Netea
Vulvovaginal candidiasis (VVC) is a widespread vaginal infection primarily caused by Candida albicans. VVC affects up to 75% of women of childbearing age once in their life, and up to 9% of women in different populations experience more than three episodes per year, which is defined as recurrent vulvovaginal candidiasis (RVVC). RVVC results in diminished quality of life as well as increased associated healthcare costs. For a long time, VVC has been considered the outcome of inadequate host defenses against Candida colonization, as in the case of primary immunodeficiencies associated with persistent fungal infections and insufficient clearance. Intensive research in recent decades has led to a new hypothesis that points toward a local mucosal overreaction of the immune system rather than a defective host response to Candida colonization. This review provides an overview of the current understanding of the host immune response in VVC pathogenesis and suggests that a tightly regulated fungus–host–microbiota interplay might exert a protective role against recurrent Candida infections.

24 October 2020 in Infectious Diseases
Verified
Journal Article
Open access
ZKZara Karami
Zara Karami
BKBram T. Knoop
Bram T. Knoop
ADAnton S. M. Dofferhoff
Anton S. M. Dofferhoff
MBMarc J. T. Blaauw
Marc J. T. Blaauw
Nico JanssenNico Janssen
Nico Janssen
JOJaap ten Oever
Jaap ten Oever
Knowledge on bacterial co-infections in COVID-19 is crucial to use antibiotics appropriately. Therefore, we aimed to determine the incidence of bacterial co-infections, antibiotic use and applicati...

5 March 2022 in Clinical Infectious Diseases
Verified
Journal Article
Open access
PDF file
SMSimone J C F M Moorlag
Simone J C F M Moorlag
ETEsther Taks
Esther Taks
TDThijs Ten Doesschate
Thijs Ten Doesschate
TVThomas W van der Vaart
Thomas W van der Vaart
AJAxel B Janssen
Axel B Janssen
MNMihai G. Netea
Mihai G. Netea
Background: Older age is associated with increased severity and death from respiratory infections, including coronavirus disease 2019 (COVID-19). The tuberculosis BCG vaccine may provide heterologous protection against nontuberculous infections and has been proposed as a potential preventive strategy against COVID-19. Methods: In this multicenter, placebo-controlled trial, we randomly assigned older adults (aged ≥60 years; n = 2014) to intracutaneous vaccination with BCG vaccine (n = 1008) or placebo (n = 1006). The primary end point was the cumulative incidence of respiratory tract infections (RTIs) that required medical intervention, during 12 months of follow-up. Secondary end points included the incidence of COVID-19, and the effect of BCG vaccination on the cellular and humoral immune responses. Results: The cumulative incidence of RTIs requiring medical intervention was 0.029 in the BCG-vaccinated group and 0.024 in the control group (subdistribution hazard ratio, 1.26 [98.2% confidence interval, .65–2.44]). In the BCG vaccine and placebo groups, 51 and 48 individuals, respectively tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with polymerase chain reaction (subdistribution hazard ratio, 1.053 [95% confidence interval, .71–1.56]). No difference was observed in the frequency of adverse events. BCG vaccination was associated with enhanced cytokine responses after influenza, and also partially associated after SARS-CoV-2 stimulation. In patients diagnosed with COVID-19, antibody responses after infection were significantly stronger if the volunteers had previously received BCG vaccine. Conclusions: BCG vaccination had no effect on the incidence of RTIs, including SARS-CoV-2 infection, in older adult volunteers. However, it improved cytokine responses stimulated by influenza and SARS-CoV-2 and induced stronger antibody titers after COVID-19 infection. Clinical trials registration: EU Clinical Trials Register 2020-001591-15 ClinicalTrials.gov NCT04417335.

19 November 2014 in BMC Immunology
Verified
Journal Article
Open access
PDF file
JOJaap ten Oever
Jaap ten Oever
MKMatthijs Kox
Matthijs Kox
FVFrank van de Veerdonk
Frank van de Veerdonk
KMKhutso M Mothapo
Khutso M Mothapo
ASAdriana Slavcovici
Adriana Slavcovici
MNMihai G. Netea
Mihai G. Netea
The extracellular domains of cytokine receptors are released during inflammation, but little is known about the shedding of Toll-like receptors (TLR) and whether they can be used as diagnostic biomarkers. The release of sTLR2 and sTLR4 was studied in in-vitro stimulations, as well as in-vivo during experimental human endotoxemia (n = 11, 2 ng/kg LPS), and in plasma of 394 patients with infections (infectious mononucleosis, measles, respiratory tract infections, bacterial sepsis and candidemia) or non-infectious inflammation (Crohn’s disease, gout, rheumatoid arthritis, autoinflammatory syndromes and pancreatitis). Using C-statistics, the value of sTLR2 and sTLR4 levels for discrimination between infections and non-infectious inflammatory diseases, as well as between viral and bacterial infections was analyzed. In-vitro, peripheral blood mononuclear cells released sTLR2 and sTLR4 by exposure to microbial ligands. During experimental human endotoxemia, plasma concentrations peaked after 2 hours (sTLR4) and 4 hours (sTLR2). sTLR4 did not correlate with cytokines, but sTLR2 correlated positively with TNFα (rs = 0.80, P < 0.05), IL-6 (rs = 0.65, P < 0.05), and IL-1Ra (rs = 0.57, P = 0.06), and negatively with IL-10 (rs = -0.58, P = 0.06), respectively. sTLR4 had a similar area under the ROC curve [AUC] for differentiating infectious and non-infectious inflammation compared to CRP: 0.72 (95% CI 0.66-0.79) versus 0.74 (95% CI 0.69-0.80) [P = 0.80], while sTLR2 had a lower AUC: 0.60 (95% CI 0.54-0.66) [P = 0.0004]. CRP differentiated bacterial infections better from viral infections than sTLR2 and sTLR4: AUC 0.94 (95% CI 0.90-0.96) versus 0.58 (95% CI 0.51-0.64) and 0.75 (95% CI 0.70-0.80), respectively [P < 0.0001 for both]. sTLRs are released into the circulation, and suggest the possibility to use sTLRs as diagnostic tool in inflammatory conditions.

9 November 2022 in Journal of Infection
Verified
Journal Article
Open access
IKIlse J.E. Kouijzer
Ilse J.E. Kouijzer
VFVance G. Fowler
Vance G. Fowler
JOJaap ten Oever
Jaap ten Oever
The current duration of therapy in patients with Staphylococcus aureus bacteremia (SAB) is based on differentiating complicated from uncomplicated disease. While this approach allows clinicians and investigators to group SAB patients into broadly similar clinical categories, it fails to account for the intrinsic heterogeneity of SAB. This is due in part to the fact that risk factors for metastatic infection and confirmed metastatic infection are considered as equivalent in most scoring systems. In this viewpoint, we propose a two-step system of categorizing patients with SAB. Initially, patients with SAB would be categorized as 'high risk' or 'low risk' for metastatic infection based upon an initial set of diagnostic procedures. In the second step, patients identified as 'high-risk' would undergo additional diagnostic evaluation. The results of this stepwise diagnostic evaluation would define a 'final clinical diagnosis' to inform an individualized final treatment plan.