Seroprevalence of SARS-CoV-2 antibodies among healthcare workers in Dutch hospitals after the 2020 first wave: a multicentre cross-sectional study with prospective follow-up.

Background: We aimed to estimate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence and describe its determinants and associated symptoms among unvaccinated healthcare workers (HCWs) after the first wave of the pandemic.

Methods: HCWs from 13 Dutch hospitals were screened for antibodies against the spike protein of SARS-CoV-2 in June-July 2020 and after three months. Participants completed a retrospective questionnaire on determinants for occupational and community exposure to SARS-CoV-2 and symptoms suggestive of COVID-19 experienced since January 2020.

Pre-Operative SARS-CoV-2 Testing in Asymptomatic Heart Transplantation Recipients.

Introduction: From the start of the coronavirus disease 2019 (COVID-19) pandemic, international guidelines have recommended pre-operative screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before heart transplantation (HTx). Due to the changing prevalence of COVID-19, the chances of false positive results have increased. Because of increased immunity in the population and evolution of SARS-CoV-2 to current Omicron variants, associated mortality and morbidity have decreased.

Cost Effectiveness of Rectal Culture-based Antibiotic Prophylaxis in Transrectal Prostate Biopsy: The Results from a Randomized, Nonblinded, Multicenter Trial.

Background: Culture-based antibiotic prophylaxis is a plausible strategy to reduce infections after transrectal prostate biopsy (PB) related to fluoroquinolone-resistant pathogens.

Objective: To assess the cost effectiveness of rectal culture-based prophylaxis compared with empirical ciprofloxacin prophylaxis.

Design Setting And Participants: The study was performed alongside a trial in 11 Dutch hospitals investigating the effectiveness of culture-based prophylaxis in transrectal PB between April 2018 and July 2021 (trial registration number: NCT03228108).

Rectal Culture-Based Versus Empirical Antibiotic Prophylaxis to Prevent Infectious Complications in Men Undergoing Transrectal Prostate Biopsy: A Randomized, Nonblinded Multicenter Trial.

Background: An increase in infections after transrectal prostate biopsy (PB), related to an increasing number of patients with ciprofloxacin-resistant rectal flora, necessitates the exploration of alternatives for the traditionally used empirical prophylaxis of ciprofloxacin. We compared infectious complication rates after transrectal PB using empirical ciprofloxacin prophylaxis versus culture-based prophylaxis.

Methods: In this nonblinded, randomized trial, between 4 April 2018 and 30 July 2021, we enrolled 1538 patients from 11 Dutch hospitals undergoing transrectal PB.

Adaptation, spread and transmission of SARS-CoV-2 in farmed minks and associated humans in the Netherlands.

In the first wave of the COVID-19 pandemic (April 2020), SARS-CoV-2 was detected in farmed minks and genomic sequencing was performed on mink farms and farm personnel. Here, we describe the outbreak and use sequence data with Bayesian phylodynamic methods to explore SARS-CoV-2 transmission in minks and humans on farms. High number of farm infections (68/126) in minks and farm workers (>50% of farms) were detected, with limited community spread.

Increasing the Efficiency of a National Laboratory Response to COVID-19: a Nationwide Multicenter Evaluation of 47 Commercial SARS-CoV-2 Immunoassays by 41 Laboratories.

In response to the worldwide pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the subsequent antibody tests that flooded the market, a nationwide collaborative approach in the Netherlands was employed. Forty-one Dutch laboratories joined forces and shared their evaluation data to allow for the evaluation of a quantity of serological assays for SARS-CoV-2 that exceeds the capacity of each individual laboratory. As of April 2020, these performance data had been aggregated and shared in regularly updated reports with other laboratories, Dutch government, public health organizations, and the public.

[Experiences of (care) professionals during a COVID-19 outbreak and results of serological tests in the staff of a heavily affected nursing home.].

Despite compliance with national (RIVM) guidelines, nursing home Mariënburght (the Netherlands) was severely affected during the first COVID-19 wave: 68 (68%) of the residents were infected. This resulted in a large emotional impact on the (nursing) staff. This study aims to describe the experiences of (nursing) staff, as well as the results of serological tests on COVID-19 that have been administered to professionals.

The Value of F-FDG PET/CT in Diagnosis and During Follow-up in 273 Patients with Chronic Q Fever.

In 1%-5% of all acute Q fever infections, chronic Q fever develops, mostly manifesting as endocarditis, infected aneurysms, or infected vascular prostheses. In this study, we investigated the diagnostic value of F-FDG PET/CT in chronic Q fever at diagnosis and during follow-up. All adult Dutch patients suspected of chronic Q fever who were diagnosed since 2007 were retrospectively included until March 2015, when at least one F-FDG PET/CT scan was obtained.

Vascular complications and surgical interventions after world's largest Q fever outbreak.

Objective: Since chronic Q fever often develops insidiously, and symptoms are not always recognized at an early stage, complications are often present at the time of diagnosis. We describe complications associated with vascular chronic Q fever as found in the largest cohort of chronic Q fever patients so far.

Methods: Patients with proven or probable chronic Q fever with a focus of infection in an aortic aneurysm or vascular graft were included in this study, using the Dutch national chronic Q fever database.

Chronic Q fever diagnosis— consensus guideline versus expert opinion.

Chronic Q fever, caused by Coxiella burnetii, has high mortality and morbidity rates if left untreated. Controversy about the diagnosis of this complex disease has emerged recently. We applied the guideline from the Dutch Q Fever Consensus Group and a set of diagnostic criteria proposed by Didier Raoult to all 284 chronic Q fever patients included in the Dutch National Chronic Q Fever Database during 2006–2012.

Chronic Q fever in the Netherlands 5 years after the start of the Q fever epidemic: results from the Dutch chronic Q fever database.

Coxiella burnetii causes Q fever, a zoonosis, which has acute and chronic manifestations. From 2007 to 2010, the Netherlands experienced a large Q fever outbreak, which has offered a unique opportunity to analyze chronic Q fever cases. In an observational cohort study, baseline characteristics and clinical characteristics, as well as mortality, of patients with proven, probable, or possible chronic Q fever in the Netherlands, were analyzed.

[Intestinal perforation caused by Salmonella typhimurium].

Background: In most patients, infection with a non-typhoid Salmonella species usually results in self-limiting gastroenteritis. Severe complications such as bacteraemia and extra-abdominal infections are most often attributed to typhoid subspecies like S. typhi and S.

Large regional differences in serological follow-up of Q fever patients in the Netherlands.

Background: During the Dutch Q fever epidemic more than 4,000 Q fever cases were notified. This provided logistical challenges for the organisation of serological follow-up, which is considered mandatory for early detection of chronic infection. The aim of this study was to investigate the proportion of acute Q fever patients that received serological follow-up, and to identify regional differences in follow-up rates and contributing factors, such as knowledge of medical practitioners.

David procedure during a reoperation for ongoing chronic Q fever infection of an ascending aortic prosthesis.

Chronic Q fever infections, caused by Coxiella burnetii, are associated with cardiovascular complications, mainly endocarditis and vascular (graft) infections. We report a case of a patient with a C. burnetii infected thoracic aorta graft treated initially in a conservative way.

Microbiological challenges in the diagnosis of chronic Q fever.

Diagnosis of chronic Q fever is difficult. PCR and culture lack sensitivity; hence, diagnosis relies mainly on serologic tests using an immunofluorescence assay (IFA). Optimal phase I IgG cutoff titers are debated but are estimated to be between 1:800 and 1:1,600.

[Laboratory diagnosis of acute Q fever].

In the Netherlands an increasing number of laboratories are involved in diagnosing acute Q-fever. More uniformity in diagnostics and interpretation is desirable. To enable this, a working group on diagnostics of acute Q-fever was created on the initiative of the National Institute for Public Health and the Environment (RIVM) and the Dutch Association for Medical Microbiology (NVMM).