Objective: To analyze the epidemiological characteristics and influencing factors of COVID-19 confirmed cases with viral nucleic acid re-positive in anal and/or throat swabs after discharge during the domestic imported epidemic stage in Guangdong Province in early 2020. Methods: The COVID-19 confirmed cases with the onset time before March 1, 2020 in Guangdong Province were collected to analyze the demographic data, epidemiological characteristics, and specimen collection and testing data after discharge. Logistic regression model was used for influencing factors analysis of re-positive cases. Results: A total of 1 286 COVID-19 confirmed cases were included, the M(Q1,Q3) of age was 44(32,58)years, 617 cases were male, 224 cases were re-positive in anal and/or throat swabs with the re-positive rate 17.42%. The M(Q1,Q3) of age of re-positive cases was 35(23, 50) years, which was younger than that of re-negative cases age was those 46(33, 59) years (P<0.001). With the increase of age, re-positive rate decreased (χ2trend=52.73, P<0.001). 85.27% (191/224) of re-positive cases were found in 14 d after discharge, the duration time of re-positive status was 13(7, 24) d, and 81.69% (183/224) of re-positive cases were re-tested negative in 28 d after re-positive date. No fever and other symptoms had been observed among re-positive cases during the whole follow-up. No secondary infectious cases had been found among close contacts after 14 d of centralized isolation and sampling screening. Univariate logistic regression model analysis revealed that the influencing factors of the re-positive cases included age, occupation, clusters, clinical types, and admission time. Multivariate logistic regression model analysis revealed that age was an independent risk factor. Conclusions: SARS-CoV-2 viral nucleic acid re-positive is found in COVID-19 confirmed cases after discharge in Guangdong Province. Most re-positive cases are confirmed among 14 d after discharge and re-test to negative among 28 d after re-positive date. Age is an risk factor for re-positive cases after discharge.
目的： 分析广东省2020年初国内输入疫情阶段新型冠状病毒肺炎（新冠肺炎）确诊病例出院后复检新型冠状病毒核酸阳性（复检阳性）特征及影响因素。 方法： 收集广东省新冠肺炎确诊病例（发病时间在2020年3月1日以前）的人口学资料、流行病学调查及出院后标本采集与检测等信息。采用logistic回归模型分析确诊病例复检阳性的影响因素。 结果： 研究共纳入1 286例新冠肺炎确诊病例，年龄M（Q1，Q3）为44（32，58）岁，男性617例，224例为咽拭子和/或肛拭子复检阳性，复检阳性率为17.42%。复检阳性病例年龄［M（Q1，Q3）为35（23，50）岁］小于复检阴性确诊病例年龄［M（Q1，Q3）为46（33，59）岁］（P<0.001）。随着年龄的增长复检阳性率呈下降趋势（χ2趋势=52.73，P<0.001）。85.27%（191/224）病例在14 d内复检阳性；复检阳性持续时间为13（7，24）d；81.69%（183/224）病例在复检阳性后28 d内复检核酸转阴。所有复检阳性病例在随访期间均未出现发热等症状，密切接触者经14 d集中隔离与采样排查均未发现继发感染者。单因素logistic回归模型分析结果显示，出院确诊病例复检阳性的影响因素包括年龄、职业、聚集情况、临床类型、发病入院时间。多因素logistic回归模型分析结果显示，年龄是确诊病例出院后复检阳性的独立危险因素。 结论： 广东省新冠肺炎确诊病例出院后存在复检阳性现象，且多数发生在出院14 d内，复检阳性病例多在28 d内转阴；年龄是确诊病例出院后复检阳性的危险因素。.