Background The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to a significant number of mortalities worldwide. COVID-19 poses a serious threat to human life. The clinical manifestations of COVID-19 are diverse and severe and 20% of infected patients are reported to be in a critical condition. A loss in lung function and pulmonary fibrosis are the main manifestations of patients with the severe form of the disease. The lung function is affected, even after recovery, thereby greatly affecting the psychology and well-being of patients, and significantly reducing their quality of life. Methods Participants must meet the following simultaneous inclusion criteria: over 18 years of age, should have recovered from severe or critical COVID-19 cases, should exhibit pulmonary fibrosis after recovery, and should exhibit Qi-Yin deficiency syndrome as indicated in the system of traditional Chinese medicine (TCM). The eligible candidates will be randomized into treatment or control groups. The treatment group will receive modern medicine (pirfenidone) plus TCM whereas the control group will be administered modern medicine plus TCM placebo. The lung function index will be continuously surveyed and recorded. By comparing the treatment effect between the two groups, the study intend to explore whether TCM can improve the effectiveness of modern medicine in patients with pulmonary fibrosis arising as a sequelae after SARS-CoV-2 infection. Discussion Pulmonary fibrosis is one of fatal sequelae for some severe or critical COVID-19 cases, some studies reveal that pirfenidone lead to a delay in the decline of forced expiratory vital capacity, thereby reducing the mortality partly. Additionally, although TCM has been proven to be efficacious in treating pulmonary fibrosis, its role in treating pulmonary fibrosis related COVID-19 has not been explored. Hence, a multicenter, parallel-group, randomized controlled, interventional, prospective clinical trial has been designed and will be conducted to determine if a new comprehensive treatment for pulmonary fibrosis related to COVID-19 is feasible and if it can improve the quality of life of patients. Trial registration: This multicenter, parallel-group, randomized controlled, interventional, prospective trial was registered at the Chinese Clinical Trial Registry (ChiCTR2000033284) on 26th May 2020 (prospective registered).

Background As of July 24 2020, the global reported number of COVID-19 cases was > 15.4 millions, with over 640,000 deaths. The present study aimed to carry out an epidemiological analysis of confirmed cases and asymptomatic infections in Shenzhen City to provide scientific reference for the prevention and control of COVID-19. Methods The epidemiological information of the 462 confirmed cases and 45 asymptomatic infections from January 19th to June 30th was collected in Shenzhen City, Southern China, and a descriptive analysis was performed. Results A total of 462 confirmed COVID-19 cases from January 19 to April 30, 2020 were reported in Shenzhen City, including 423 domestic cases (91.56%) and 39 imported cases (8.44%) who came back from other countries. Among domestic cases, the majority were cases imported from Hubei Province (n = 312, 67.53%), followed by local ones (n = 69, 14.94%). During the same period, a total of 45 asymptomatic infections were reported in Shenzhen City, including 31 local ones (68.89%) and 14 imported from abroad (31.11%). The proportion of asymptomatic infections in Shenzhen City was increasing over time (Z = 13.1888, P < 0.0001). The total number of local asymptomatic infections in Shenzhen City exceeded as the same pattern as that in other provinces (χ2 = 118.830, P < 0.0001). The proportion of asymptomatic infections among cases imported from abroad was higher than that of the same in domestic cases (χ2 = 22.5121, P < 0.0001, OR = 4.8983, 95%: 2.4052, 9.9756). No statistical significance was noted in the proportions of asymptomatic infections among imported cases from different countries (χ2 = 7.7202, P = 0.6561). Conclusions The majority of COVID-19 cases in Shenzhen City were imported cases who came back from Hubei Province in the early stage (before 1st March, 2020) and from abroad in the later stage (after 1st April, 2020). Scientific and effective prevention and control measures have resulted in only a few local infections in Shenzhen City. Asymptomatic infections accounted for an increasing proportion among cases imported from abroad, indicating that the prevention measures carried out in Shenzhen City did avoid the import of infected cases. Improving the detection capability to identify asymptomatic infections as early as possible will be of significance for the control outbreak of COVID-19.