Early immune profiling reveals distinct inflammatory responses between children and adults few days after primary SARS-CoV-2 infection.

Background: To date, it is still not clear why during the COVID-19 pandemic children generally developed no or milder symptoms compared to adults. As innate immune responses are crucial in the early defense against pathogens, we aimed at profiling these responses from both adults and children with a primary SARS-CoV-2 infection.

Methods: In the first months of the pandemic, PBMCs and serum were collected from peripheral blood of adults and children at different time points after testing SARS-CoV-2 PCR positive (PCR+).

Circulation of avian Chlamydia abortus in the Netherlands and community-acquired pneumonia: an outbreak investigation and retrospective cohort study.

Background: In 2021, a novel group of Chlamydia strains in wild birds was classified as avian Chlamydia abortus, with unknown zoonotic potential. We report relevant features of avian C abortus infections from a Dutch family cluster and unrelated historical cases using clinical, epidemiological, and microbiological data.

Methods: An outbreak of avian C abortus started in the Netherlands in December, 2022.

Delineating immune variation between adult and children COVID-19 cases and associations with disease severity.

The SARS-CoV-2 pandemic has emphasized the need to explore how variations in the immune system relate to the severity of the disease. This study aimed to explore inter-individual variation in response to SARS-CoV-2 infection by comparing T cell, B cell, and innate cell immune subsets among primary infected children and adults (i.e.

Targeted Screening for Chronic Q Fever, the Netherlands.

Early detection of and treatment for chronic Q fever might prevent potentially life-threatening complications. We performed a chronic Q fever screening program in general practitioner practices in the Netherlands 10 years after a large Q fever outbreak. Thirteen general practitioner practices located in outbreak areas selected 3,419 patients who had specific underlying medical conditions, of whom 1,642 (48%) participated.

Corrigendum: Children and Adults With Mild COVID-19: Dynamics of the Memory T Cell Response Up to 10 Months.

[This corrects the article DOI: 10.3389/fimmu.2022.

SARS-CoV-2 RNA and antibody dynamics in a Dutch household study with dense sampling frame.

This study investigated the dynamics of SARS-CoV-2 infection and diagnostics in 242 household members of different ages and with different symptom severity after SARS-CoV-2 exposure early in the pandemic (March-April 2020). Households with a SARS-CoV-2 confirmed positive case and at least one child in the Netherlands were followed for 6 weeks. Naso (NP)- and oropharyngeal (OP) swabs, oral fluid and feces specimens were analyzed for SARS-CoV-2 RNA and serum for SARS-CoV-2-specific antibodies.

Seropositivity to Nucleoprotein to detect mild and asymptomatic SARS-CoV-2 infections: A complementary tool to detect breakthrough infections after COVID-19 vaccination?

Background: With COVID-19 vaccine roll-out ongoing in many countries globally, monitoring of breakthrough infections is of great importance. Antibodies persist in the blood after a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Since COVID-19 vaccines induce immune response to the Spike protein of the virus, which is the main serosurveillance target to date, alternative targets should be explored to distinguish infection from vaccination.

Children and Adults With Mild COVID-19: Dynamics of the Memory T Cell Response up to 10 Months.

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to considerable morbidity/mortality worldwide, but most infections, especially among children, have a mild course. However, it remains largely unknown whether infected children develop cellular immune memory.

Methods: To determine whether a memory T cell response is being developed, we performed a longitudinal assessment of the SARS-CoV-2-specific T cell response by IFN-γ ELISPOT and activation marker analyses of peripheral blood samples from unvaccinated children and adults with mild-to-moderate COVID-19.

Impact of Q-fever on physical and psychosocial functioning until 8 years after Coxiella burnetii infection: An integrative data analysis.

Background: This study aimed to determine short- and long-term physical and psychosocial impact of Coxiella burnetii infection in three distinct entities: Q-fever fatigue syndrome (QFS), chronic Q-fever, and patients with past acute Q-fever without QFS or chronic Q-fever.

Methods: Integrative data analysis was performed, combining original data from eight studies measuring quality of life (QoL), fatigue, physical and social functioning with identical validated questionnaires, from three months to eight years after onset infection. Linear trends in each outcome were compared between Q-fever groups using multilevel linear regression analyses to account for repeated measures within patients.

High Infection Secondary Attack Rates of Severe Acute Respiratory Syndrome Coronavirus 2 in Dutch Households Revealed by Dense Sampling.

Background: Indoor environments are considered one of the main settings for transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Households in particular represent a close-contact environment with high probability of transmission between persons of different ages and roles in society.

Methods: Households with a laboratory-confirmed SARS-CoV-2 positive case in the Netherlands (March-May 2020) were included.

[The role of children in the transmission of SARS-CoV-2].

Objective: To determine whether children play a role in the transmission of SARS-CoV-2 to other children and adults, and to gain insight into symptomatic and asymptomatic infections in children.

Design: Analysis of national COVID-19 notifications and prospective observational study in families with children.

Method: Information about COVID-19 patients and their contacts was obtained from the registration systems used by the public health services.

Objective cognitive performance and subjective complaints in patients with chronic Q fever or Q fever fatigue syndrome.

Background: Primary aim of this study was to compare cognitive performance of patients with chronic Q fever or Q fever fatigue syndrome (QFS) to matched controls from the general population, while taking performance validity into account. Second, we investigated whether objective cognitive performance was related to subjective cognitive complaints or psychological wellbeing.

Methods: Cognitive functioning was assessed with a neuropsychological test battery measuring the domains of processing speed, episodic memory, working memory and executive functioning.

Media Reports as a Source for Monitoring Impact of Influenza on Hospital Care: Qualitative Content Analysis.

Background: The Netherlands, like most European countries, has a robust influenza surveillance system in primary care. However, there is a lack of real-time nationally representative data on hospital admissions for complications of influenza. Anecdotal information about hospital capacity problems during influenza epidemics can, therefore, not be substantiated.

Explaining the long-term impact of chronic Q fever and Q fever fatigue syndrome on psychosocial functioning: A comparison with diabetes and the general population.

Objective: After Q fever infection, 1-5% of patients develop chronic Q fever, while about 20% develops Q fever fatigue syndrome (QFS). This study examines whether these two conditions have a long-term impact on psychosocial functioning compared to the general population and patients with type 2 diabetes (DM) and investigate which mediating factors influence outcomes.

Methods: Cross-sectional study was performed, measuring psychosocial functioning including quality of life (depression and satisfaction with life), anxiety, social functioning and relationship satisfaction in patients with proven or probable chronic Q fever or QFS, 5-9 years after acute Q fever infection.

Discrepancies between guidelines and clinical practice regarding prostate-specific antigen testing.

Background: Most guidelines recommend a judicious use of prostate-specific antigen (PSA) testing, whereas in daily practice, an increase of the incidence of PSA testing has been shown. Accurate up-to-date PSA test incidence rates are, however, lacking.

Objective: To investigate the PSA test incidence rates in general practices over the past 10 years and to study which factors are associated with more frequent test use.