Post COVID-19

Fatigue, cognitive problems, post-exertional malaise (PEM) and postural orthostatic tachycardia syndrome (POTS) are common and debilitating symptoms after COVID-19. The pathophysiology of post-COVID is not well understood and there is no established biomedical treatment. Treatment options for post-COVID are thus much needed. A promising candidate intervention is fluvoxamine, a selective serotonin reuptake inhibitor (SSRI), that may reduce post-COVID symptoms because of its regulatory effect on the (neuro) immune system, the hypothalamic-pituitary-adrenal (HPA) axis and the tryptophan system. The investigators will randomize 160 participants to either fluvoxamine or placebo for 12 weeks. The investigators will use advanced functional neuroimaging techniques during cognitive challenge (optional substudy) and plasma biomarkers (inflammatory markers, cortisol, serotonin, IDO-2 activity), to facilitate identifying potential mechanistic pathways of post -COVID treatment.

This randomized controlled study evaluates the effects of cold water hydrotherapy in patients with Post-COVID Syndrome. The primary aim is to assess changes in quality of life compared to an usual care setting without hydrotherapy treatment.

This randomized controlled study evaluates the effects of cold water hydrotherapy as an adjunct to standard rehabilitation in patients with Post-COVID Syndrome. The primary aim is to assess changes in quality of life compared to standard rehabilitation alone.

The aim of this study is to determine the relationship between changes in resting electrocardiography (ECG) ventricular repolarization parameters, transthoracic impedance cardiography (ICG) parameters, and COVID-19, to assess the relationship between ECG changes after COVID-19 and heart rhythm disorders (arrhythmias), cardiovascular events (the onset and exacerbation of cardiovascular diseases), the persistence of changes two years after the illness, and to identify prognostic ventricular repolarization parameters in patients with and after COVID-19. It is expected that the results obtained during the study will help predict long-term cardiovascular complications in these patients, aiming to prevent them by providing recommendations for the long-term monitoring of individuals who have recovered from COVID-19. Additionally, the investigators hope to propose a new ECG ventricular repolarization parameter that could be used in the future for prognostic assessment in patients with other diseases as well.