1. According to the standard of the Chinese version New Coronavirus Pneumonia Diagnosis and Treatment Program (5th edition), the participant is clearly diagnosed as Coronavirus Disease 2019 (COVID-19) and classified as mild or common type, 2. During treatment in hospital, the condition tends to be stable, 3. Write the informed consent form and be able to insist on long-term follow-up.

1. According to the standard of the Chinese version New Coronavirus Pneumonia Diagnosis and Treatment Program (5th edition), the participant is clearly diagnosed as Coronavirus Disease 2019 (COVID-19) and classified as mild or common type, 2. During treatment in hospital, the condition tends to be stable, 3. Write the informed consent form and be able to insist on long-term follow-up.