This retrospective multi-center matched cohort study assessed the risk for severe COVID-19
(combination of severity indicators), intensive care unit (ICU) admission, and in-hospital …

The objective of this study was to investigate the incidence and risk factors associated with
COVID-19 vaccine breakthrough infections. We included all persons≥ 18 years that had …

Background Differences in the genetic material of severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2) variants may result in altered virulence characteristics …

Background Recent studies have identified important social inequalities in SARS-CoV-2
infections and related COVID-19 outcomes in the Belgian population. The aim of our study …

Vaccination has played a major role in overcoming the COVID-19 pandemic. However,
vaccination status can be influenced by demographic and socio-economic factors at …

Introduction The pathogenesis of COVID-19 depends on the interplay between host
characteristics, viral characteristics and contextual factors. Here, we compare COVID-19 …

The notion of causality assumes a paramount position within the realm of human cognition.
Over the past few decades, there has been significant advancement in the domain of causal …

We aimed to investigate vaccine effectiveness against progression to severe COVID-19
(acute respiratory distress syndrome (ARDS), intensive care unit (ICU) admission and/or …

We investigated effectiveness of (1) mRNA booster vaccination versus primary vaccination
only and (2) heterologous (viral vector–mRNA) versus homologous (mRNA–mRNA) prime …

Since December 2019, the pandemic COVID-19 has been connected to the severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2). Early identification and diagnosis are …