Close contact tracing and management
If the discharged patient was diagnosed as a positive retest patient, close contacts should be traced and followed up. Close contacts are to be put under centralized quarantine and medical observation. If this is not feasible, home quarantine and health monitoring can be used instead. At home, they were recommended to wear a mask, live in a well-ventilated single room, reduce close contact with family members, wash hands frequently and avoid going out(Chinese_CDC, 2020). The quarantine period should last until 14 days after the last contact without effective protection with a positive retest patient. Samples including nasopharyngeal and anal swabs were all collected for RT-PCR diagnosis in an attempt to reduce the chance of false negatives caused by differences in primer specificity and sensitivity. Monitoring and evaluating close contacts were documented in a previous study(Luo, Liu, Liao, et al., 2020).