Time distribution of positive nucleic acid detection in imported cases infected with SARS-CoV-2 in China.
10.3760/cma.j.cn112338-20211108-00858
- VernacularTitle:我国输入性新型冠状病毒感染者核酸检测阳性的时间分布特征
- Author:
Zhi Li LI
1
;
Yu LI
1
;
Qiu Lan CHEN
1
;
Xin Li JIANG
1
;
Xiao Kun YANG
1
;
Ying QIN
1
;
Zhi Bin PENG
1
;
Jian Xing YU
2
;
Zhong Jie LI
3
Author Information
1. Division of Infectious Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
2. National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
3. Chinese Center for Disease Control and Prevention, Beijing 102206, China.
- Publication Type:Journal Article
- MeSH:
Asymptomatic Infections;
COVID-19;
China/epidemiology*;
Humans;
Nucleic Acids;
SARS-CoV-2
- From:
Chinese Journal of Epidemiology
2022;43(2):183-188
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To analyze the time distribution of the first positive nucleic acid detection in imported cases infected with SARS-CoV-2 reported nationwide in China and provide references for further improvement of the prevention and control of COVID-19 in international travelers. Methods: The data of imported cases infected with SARS-CoV-2 reported by provinces from 24 July 2020 and 23 July 2021 were collected for the analysis on the time distribution of the first positive nucleic acid detection after entering China. Results: A total of 7 199 imported cases infected with SARS-CoV-2 were reported in 28 provinces during 24 July 2020 to 23 July 2021. The median interval (Q1, Q3) from the entry to the first positive nucleic acid detection of SARS-CoV-2 was 1 (0, 5) day. The imported cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry accounted for 95.15% (6 850/7 199) and 4.85% (349/7 199) respectively. Among these cases, 3.65% (263/7 199), 0.88% (63/7 199) and 0.32% (23/7 199) had the first positive nucleic acid detections within 15-21 days, 22-28 days and 28 days later after the entry respectively. The proportion of asymptomatic infections were 47.24% (3 236/6 850) and 63.61% (222/349) among the cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry respectively. A total of 39.54% (138/349) of cases infected with SARS-CoV-2 with the first positive nucleic acid detections 14 days later after the entry had inter-provincial travel after the discharge of entry point isolation. Conclusions: About 5% of the imported cases infected with SARS-CoV-2 were first positive 14 days later after the entry. In order to effectively reduce the risk of domestic COVID-19 secondary outbreaks caused by imported cases, it is suggested to add a nucleic acid test on 8th -13th day after the entry.
