广州市新型冠状病毒肺炎密切接触者管理情况及效果分析

目的 分析广州市新型冠状病毒肺炎密切接触者（密接）人群管理情况及效果。方法 收集广州市报告新型冠状病毒肺炎病例密接的一般人口学、与病例关系、暴露史、管理及发病情况等信息,比较不同时期（1月21—30日、1月31日至2月8日、2月9日至3月2日）密接人群特征。结果 研究期间广州市累计追踪2 312名密接,男女性别比为1.15∶1,年龄以20~59岁为主,占73.53%;密接集中隔离率96.63%,密接病例比为8.59,密接转病例比例为5.49%,密接占报告病例比例为35.28%,最后接触至发病中位时间为2 d,发病至确诊中位时间为4 d。从第一到第三时期,集中隔离率（91.88%~97.83%,P<0.01）、密接病例比上升（3.86~41.26,P<0.01）,密接转病例比例下降（14.06%~1.13%,P<0.01）,管理密接占报告病例比例上升（23.94%~54.00%,P<0.01）,发病至确诊时间缩短（4~0 d,P<0.01）,与关联病例关系为社交活动（16.24%~42.63%）、接触频率为偶尔或一般（42.57%~90.64%）的密接占比增加（P<0.01）。全时期和第三时期密接中,发病组的最后接触至开始管理时间小于非发病组（P<0.01）。结论 广州市对新型冠状病毒肺炎密接的追踪管理工作逐步加强并取得良好效果,有效控制了疫情向社区蔓延,后续可探索根据风险因素分级的密接精准管理模式,指导精准防控。

Management and its effectiveness in close contacts of COVID-19 in Guangzhou

Objective To analyze the management and its effectiveness in close contacts of COVID-19 in Guangzhou City. Methods General demographic information,relationship and contact situation with related cases,and medical observation outcome of close contacts were collected to compare the above characteristics of close contacts in 1 st(from January 21-30),2 nd(from January 31 to February 8)and 3 rd(from February 9 to March 2)period. Results A total of2 312 close contacts were tracked. Male-to-female ratio was 1.15∶1,most of them were 20-59 years old,accounting for73.53%. Isolation rate was 96.63%,close contact to case ratio was 8.59,positive rate of close contact was 5.49%,proportion of case was 35.28%. Median time of last contact to oncome,oncome to diagnosis were 2 d and 4 d,respectively. From1 stto 3 rdperiod,isolation rate(from 91.88% to 97.83%,P<0.01)and close contact to case ratio(from 3.86 to 41.26,P<0.01)increased,positive rate of close contact(from 14.06% to 1.13%,P<0.01)decreased,proportion of case(from23.94% to 54.00%,P<0.01)increased,median time of oncome to diagnosis( from 4 d to 0 d,P<0.01)decreased.Close contacts with social contact related(from 16.24% to 42.63%,P<0.01),general or occasionally contact frequency(from 42.57% to 90.64%,P<0.01)increased. Compared with negative group,positive group had a shorter time of last contact to observe in whole period and 3 rdperiod(P<0.01).Conclusion COVID-19 has been well controlled from community epidemic by sequential strengthen and effective management of close contacts in Guangzhou City. We suggest to establish a classification scheme for close contact management of different infection risk,so as to precise prevention and control.