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Published on: December 19, 2020
Epidemiological characteristics of COVID-19 patients in convalescence period
B M Liu1, Q Q Yang1, L Y Zhao1
1Department of Nephrology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China.
Insights
Many recovered coronavirus disease 2019 (COVID-19) patients shed infectious virus despite negative RNA tests. This suggests current isolation guidelines may need re-evaluation for discharged COVID-19 patients.
Area of Science:
- Infectious Diseases
- Epidemiology
- Pulmonology
Background:
- Coronavirus disease 2019 (COVID-19) poses significant public health challenges.
- Understanding convalescent COVID-19 patients' characteristics is crucial for effective management and transmission control.
Purpose of the Study:
- To investigate the clinical characteristics of COVID-19 patients during convalescence.
- To analyze the epidemiological features of recovered COVID-19 patients.
Main Methods:
- Retrospective analysis of clinical data from 71 confirmed COVID-19 cases discharged from Zhongnan Hospital of Wuhan University.
- Statistical analysis of patient demographics, isolation duration, RNA detection, clinical symptoms, and chest CT findings.
Main Results:
- 35.2% of patients experienced a positive RNA test during convalescence, with a longest reversal time of 7 days.
- 52.9% of adult patients were asymptomatic, while others had mild symptoms. Chest CT signs improved in 89.7% of adult patients.
- Extrapulmonary manifestations were observed in 8.8% of patients, with no significant correlation to RNA detection results. Symptomatic treatment was primary; antibiotics and antivirals were ineffective.
Conclusions:
- A significant proportion of convalescent COVID-19 patients may still shed virus, necessitating a re-evaluation of isolation duration and termination standards.
- Clinical and radiological improvements do not always correlate with viral RNA shedding.
- Current treatment strategies focus on symptomatic support, highlighting the need for further research into effective antiviral therapies.
Abstract:
This study aimed to investigate the clinical characteristics and to analyse the epidemiological features of coronavirus disease 2019 (COVID-19) patients during convalescence. In this study, we enrolled 71 confirmed cases of COVID-19 who were discharged from hospital and transferred to isolation wards from 6 February to 26 March 2020. They were all employees of Zhongnan Hospital of Wuhan University or their family members of which three cases were <18 years of age. Clinical data were collected and analysed statistically. Forty-one cases (41/71, 57.7%) comprised medical faculty, young and middle-aged patients (aged ⩽60 years) accounted for 81.7% (58/71). The average isolation time period for all adult patients was 13.8 ± 6.1 days. During convalescence, RNA detection results of 35.2% patients (25/71) turned from negative to positive. The longest RNA reversed phase time was 7 days. In all, 52.9% of adult patients (36/68) had no obvious clinical symptoms, and the remaining ones had mild and non-specific clinical symptoms (e.g. cough, sputum, sore throat, disorders of the gastrointestinal tract etc.). Chest CT signs in 89.7% of adult patients (61/68) gradually improved, and in the others, the lesions were eventually absorbed and improved after short-term repeated progression. The main chest CT manifestations of adult patients were normal, GGO or fibre streak shadow, and six patients (8.8%) had extrapulmonary manifestations, but there was no significant correlation with RNA detection results (r = -0.008, P > 0.05). The drug treatment was mainly symptomatic support therapy, and antibiotics and antiviral drugs were ineffective. It is necessary to re-evaluate the isolation time and standard to terminate isolation for discharged COVID-19 patients.
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