The serum flow profile of pneumonia in COVID-19 shows that the population in China is generally at a low infection level in SARS-CoV-2. Laut der Nachrichtenagentur Xinhua, Beijing, December 29 (Reporter Tian Xiaohang Mu Tiecheng), the reporter learned from the Chinese Center for Disease Control and Prevention that one month after China curbed the first wave of COVID-19 pneumonia, …