1. Age above 18 years. 2. Able to give informed consent. 3. History of documented SARS-CoV-2 infection either by RT-PCR or antibody test. 4. Symptoms related to LTC, defined as being investigated, diagnosed and followed by specialized infectious diseases physicians in the Long Term COVID-19 Outpatient Clinic, Central Region of Denmark, Aarhus University Hospital. This clinic covers all LTC patients referred from general practitioners and regional hospitals in Region Midtjylland. 5. Symptoms not attributable to other co-morbidity/condition.

1. Age above 18 years. 2. Able to give informed consent. 3. History of documented SARS-CoV-2 infection either by RT-PCR or antibody test. 4. Symptoms related to LTC, defined as being investigated, diagnosed and followed by specialized infectious diseases physicians in the Long Term COVID-19 Outpatient Clinic, Central Region of Denmark, Aarhus University Hospital. This clinic covers all LTC patients referred from general practitioners and regional hospitals in Region Midtjylland. 5. Symptoms not attributable to other co-morbidity/condition.