Background: The coronavirus disease-19 (COVID-19) is a highly infectious disease. Moreover, 14% of the discharged patients tested virus positive again. However, the underlying clinical mechanisms are still under investigation. Case presentation: The current study summarized the clinical course, radiological features and laboratory test results of two COVID-19 patients who tested positive again during the quarantine after hospital discharge. We found that while all symptoms were relieved, their lesions in lungs were not fully recovered, and both of them had slight coughs. In addition, when the lesions were further recovered and the cough symptoms were further remitted, they tested virus negative again. Conclusions: These results implied that the positive result is unlikely caused by the reinfection from others or the remained virus. Rather, it may derive from the remained virus transferred from the lower respiratory tract to the throat or nose with coughs. Accordingly, we proposed some suggestions regarding the discharge management. This study enhances our knowledge of the progress of COVID-19 and benefit the control of this disease.
