目的 探讨新型冠状病毒无症状感染者筛查和带毒时间。方法 主动搜索高危人群采集咽拭子标本进行新冠病毒核酸检测,并进行描述流行病学分析。结果 筛查1 497人,新型冠状病毒无症状感染者13例,阳性检出率0.87%。其中密切接触者阳性率2.06%,境外回国人员阳性率0.14%,特定人群中BM人群筛查阳性率为0.66%,三类人群新型冠状病毒核酸阳性率差异有统计学意义(χ²=12.525,P=0.002),其中密切接触人群筛查阳性率高于境外回国和BM商场两类人群筛查阳性率。带毒时间最短9 d,最长39 d,中位数15 d,2例病例出现复阳;末次暴露至检测阳性时间间隔最短3 d,最长24 d,中位数14 d。13例无症状感染者的密切接触者检查均为阴性。结论 13例无症状感染者主要来源于密切接触者,带毒时间较长,多数病例早发现、早隔离,未造成社区传播。

Objective To investigate the novel coronavirus asymptomatic infection screening and taking time. Methods Throat swab samples were collected from high-risk groups for detection of NCV nucleic acid,and descriptive epidemiological analysis was conducted. Results The novel coronavirus was screened for 1497 cases,and 13 cases were asymptomatic.The positive rate was 0.87%.The positive rate of the close contacts was 2.06%,and the positive rate of overseas returnees was 0.14%.The positive rate of BM screening among the specific population was 0.66%.The positive rate of new coronavirus nucleic acid in three groups was statistically significant (χ²=12.525,P=0.002),and the positive rate of the close contact population was higher than that of the two groups of overseas visitors and BM shopping malls.The shortest time of carrying virus was 9d,the longest was 39d,and the median was 15d.The interval between the last exposure and positive detection was 3 days,the longest was 24 days,and the median was 14 days.The close contacts of 13 asymptomatic patients were negative. Conclusion 13 asymptomatic infections were mainly from close contacts,with a long time of carrying the virus.Most of the cases were found early and isolated early,which did not cause community transmission.