Post-COVID Syndrome

Background: As defined by the WHO, the term post-COVID syndrome (PCS) embraces a group of symptoms that can occur fol-lowing the acute phase of a SARS-CoV-2 infection and as a consequence thereof. PCS is found mainly in adults, less frequently in children and adolescents. It can develop both in patients who initially had only mild symptoms or none at all and in those who had a severe course of coronavirus disease 2019 (COVID-19). Methods: The data presented here were derived from a systematic literature review. Results: PCS occurs in up to 15% of unvaccinated adults infected with SARS-CoV-2. The prevalence has decreased in the most recent phase of the pandemic and is lower after vaccination. The pathogenesis of PCS has not yet been fully elucidated. Virus -triggered inflammation, autoimmunity, endothelial damage (to blood vessels), and persistence of virus are thought to be causative. Owing to the broad viral tropism, different organs are involved and the symptoms vary. To date, there are hardly any evidence-based recommendations for definitive diagnosis of PCS or its treatment. Conclusion: The gaps in our knowledge mean that better documentation of the prevalence of PCS is necessary to compile the data on which early detection, diagnosis, and treatment can be based. To ensure the best possible care of patients with PCS, regional PCS centers and networks embracing existing structures from all healthcare system sectors and providers should be set up and structured diagnosis and treatment algorithms should be established. Given the sometimes serious consequences of PCS for those affected, it seems advisable to keep the number of SARS-CoV-2 infections low by protective measures tailored to the prevailing pandemic situation.