某区新型冠状病毒无症状感染者发现途径与带毒时间分析

Discovery of novel coronavirus asymptomatic infection and the time of carrying virus in a district

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1497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(χ^(2)=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(χ^(2)=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 9 d,the longest was 39 d,and the median was 15 d.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.