1. Monitor the incidence of COVID-19, and the development of the SARS-CoV-2-IgG levels of cases in Telemark and Agder over a period of two years (Work Package [WP] 1).
  2. Identify risk factors for COVID-19 by comparison of antibody IgG positive and negative cases, and by comparison of these groups separately with population controls (WP2).
  3. The incidence of neurocognitive symptoms and fatigue in COVID-19 patients (WP3).
  4. Investigation of severity, death and the use of health care for the COVID-19 patients based on data from national registers (WP4).