Repeat testing raises questions

A study following a small series of patients indicates that individuals considered to have recovered from COVID-19 may still be carrying the virus. The authors have suggested a possible need to re-evaluate current criteria for hospital discharge/discontinuation of quarantine and for continued management of patients with COVID-19. The paper was published online as a research letter in JAMA on April 21, 2020. Written by Lan Lan MD and colleagues from China, it reported on four patients treated at Zhongnan Hospital of Wuhan University, Wuhan, China, who consistently had positive results on repeat real-time reverse transcriptase-polymerase chain reaction (RT-PCR) testing performed after they had recovered from COVID-19. Each patient had three RT-PCR tests performed over a period of five-to-13 days after having met criteria for discharge from hospital or home quarantine. The testing was done using a kit recommended by the Chinese Center for Disease Control and Prevention, the same technician performed all of the testing and both internal controls and negative controls were performed with each batch of tests. Post-recovery testing using a kit from a different manufacturer also yielded positive results. The four patients were all medical professionals and had mild-to-moderately severe disease. The small cohort included two males and two females, and they ranged in age from 30-to-36 years. One patient had been treated as an inpatient and the others stayed under home quarantine after diagnosis with COVID-19. Three of the patients presented with fever and/or cough. All showed ground-glass opacification or mixed ground-glass opacification and consolidation on computed tomography (CT) imaging. One patient who was initially asymptomatic underwent CT imaging because of a history of exposure to patients with COVID-19. To be eligible for hospital discharge or discontinuation of quarantine, the patients were required to have a normal temperature for >3 days, absence of respiratory symptoms, substantially improved acute exudative lesions on CT and two consecutively negative RT-PCR tests from throat swabs obtained with an inter-test interval of at least one day. The patients all remained on home quarantine for five days after meeting the criteria for discharge or discontinuation of quarantine. During the follow-up period, none of the patients developed recurrent symptoms or radiologic changes. All denied having infected family members or contact with any other person who had respiratory symptoms. The authors suggested that further studies with a larger number of patients, including non-medical personnel and those with severe COVID-19, would be helpful to gain understanding about the prognosis of the infection.

Tags: covid-19 research