Asymptomatic COVID-19 Have Longer Treatment Cycle Than Moderate Type of Confirmed Patients

Zhang, Wei; Long, Qinying; Huang, Yanbiao; Chen, Changju; Wu, Jinhua; Hong, Yang; Zhou, Hourong; Wu, Weidong

Objectives A kind of pneumonia caused by unknown causes that occurred in Wuhan, Hubei, China in December 2019, was reported as a result of novel coronavirus infection on January 7, 2020, and then WHO named it COVID-19. To compare the difference of epidemiology and clinical characteristics between asymptomatic COVID-19 infections and moderate type of confirmed cases. Methods Retrospective, single-center cohort study of COVID-19 involving 52 infections of both 26 asymptomatic and 26 moderate type of confirmed cases in the recovery stage at Guizhou Provincial Staff Hospital in Guiyang, China, from January 29, to March 31, 2020; final date of follow-up was April 22. This study was registered in Chinese Clinical Trial Registry Center. Documented the asymptomatic COVID-19 infections and moderate type of confirmed cases. Epidemiological, demographic, clinical, laboratory, radiological, and treatment data were collected and analyzed. Epidemiological and clinical characteristics of asymptomatic COVID-19 infections and moderate type of confirmed cases were compared. Results The median treatment cycle of asymptomatic COVID-19 infections was 16 days (interquartile range, 11-20 days) and longer than 13 days (interquartile range, 10-15 days) of moderate type of confirmed cases (p=0.049). The median incubation period of asymptomatic COVID-19 infections was 10 days (interquartile range, 0-21 days), while the control group was 7 days (interquartile range, 1-15 days) (p=0.27). On the initial chest computerized tomography (CT) check, 18 (69.2%, 18/26) asymptomatic COVID-19 infections were no imaging changes, which was of no significance compared with 12 (46.2%, 12/26) patients with moderate type of confirmed patients (p=0.092). Conclusions In this single-center study, we found that asymptomatic COVID-19 infections have longer treatment cycle than those moderate type of confirmed cases.