SAR-Cov-2 infection and its clinical manifestation known as COVID-19 beside the respiratory and lung involvement may include the cardiovascular system, the nervous system and the liver. In the acute phase of the disease, all of these conditions may be life-threatened. As a result, after the acute phase of COVID-19, early complications may be observed, including heart, lungs, brain, muscles and liver. A few papers to date have been reported of myocarditis, ventricular arrhythmias, post-inflammatory changes in the lung and liver, as well as ischemic changes in the brain, diseases of skeletal muscle, which may have adverse prognostic effects. Due to the extent of the pandemic, the severity of the complications and the expected high complications' prevalence in the early post-recovery period, a study was designed to determine the extent of the problem of early complications after COVID-19. Complex cardiological, pulmonary, neurological and hepatological diagnostics are planned, including laboratory, imaging and functional tests. The results obtained, in addition to determining the scale of the problem, will allow the selection of studies that optimally identify patients with early complications. The purpose of this procedure is to enable rapid treatment of diseases that are complications of SARS-COV-2 infection. An additional aspect raised in the project will be the issue of psychiatric disorders (anxiety, depression, post traumatic disorders).

The main three purposes of the study include:

1. the assessment of prevalence of particular complications after COVID-19.
2. identification of the demographic and clinical risk factors of COVID-19 complications
3. determining the diagnostic tests which are sufficient to detect early complications of COVID-19

Inclusion Criteria:

1. SARS-Cov-2 RNA confirmed by the PCR method in the acute phase of disease.
2. Presence of the clinical symptoms associated with COVID-19 in the acute phase of disease
3. Two negative results of SARS-COV-2 PCR test following the 7-day period of quarantine
4. Informed consent

Exclusion Criteria:

1. Any symptoms of infection during the quarantine
2. Lack of patient's consent
3. Lack of possibility of travelling to the hospital for tests

Patients who recovered from COVID-19 in Silesia, Poland.