Confirmed casesA positive case is confirmed after consulting medical experts, epidemiological survey, inspection of clinical symptoms, laboratory test and imagological examination.They are quarantined and treated mainly at the Shanghai Public Health Clinical Center with a combination of anti-infection therapy, traditional Chinese medicine, nutrition, psychological counseling and other remedies.Asymptomatic casesAn asymptomatic case is tested positive for COVID-19, but shows no clinical symptoms. A small portion of such cases might show symptoms later and become a confirmed case.