Introduction
As a result of imperfect immune function, children are naturally susceptible to various respiratory viruses and not easy to spontaneously resolve.Since the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection began in Wuhan city,Hubei province, China.1-2 more than 2,000 pediatric cases have been reported nationwide in just over two months.3 Recently, an increasing number of coronavirus disease 2019 (COVID-19) patients were discharged from the hospital and received regular follow-up and observation. Re-detectable positive (RP) of SARS-CoV-2 RNA test in some recovered patients has been reported.4 Our hospital also reported that 38 of the 262 cured and discharged patients were found to be RP during the convalescence. Among them, patients younger than 14 years old were more common compared with those between the ages of 14 and 60 years.5 In the long-term follow-up,we also observed that a large proportion of pediatric patients were RP (nasopharyngeal swabs and/or anal swabs) after discharge,even repeated RP and several readmission, asymptoms or with mild symptoms, and chest computed tomography (CT) showed sustained remission of pulmonary lesions.Obviously,RP means that the virus has not been completely cleared.There is still some uncertainty about whether such patients are infectious,but it undoubtedly has a serious impact on the formulation and implementation of prevention and control measures.
Despite great advances in rapid detection, diagnosis and treatment in SARS-CoV-2 infection, little is known about the early risk factors for RP.In particular, data on convalescent children as a special population have not been reported.We aimed to identify the early risk factors for RP, and to provide a basis for early clinical prediction and risk stratification.