COVID-19, which is caused by the SARS-CoV-2 virus, induces in 5 to 15% of cases a severe phenotype with bilateral pneumonia, sometimes complicated by an acute respiratory distress syndrome and respiratory failure. Patients present with lymphopenia and possibly neutrophilia, which are of prognostic relevance. In addition, some patients develop immune overactivation, which is associated with a cytokine storm and a poor prognosis. Although the underlying mechanisms remain poorly understood, the virus’ ability to escape immune mechanisms could play an important role. An improved understanding of the disease immunopathology should help defining a precision medicine to treat COVID-19 patients based on predictive (or early) biomarkers of severity.
COVID-19, immunopathology, immune activation, ARDS