Epidemiological characteristics of infection in COVID-19 close contacts in Ningbo city
10.3760/cma.j.cn112338-20200304-00251
- VernacularTitle:宁波市新型冠状病毒肺炎密切接触者感染流行病学特征分析
- Author:
Yi CHEN
1
;
Aihong WANG
;
Bo YI
;
Keqin DING
;
Haibo WANG
;
Jianmei WANG
;
Hongbo SHI
;
Sijia WANG
;
Guozhang XU
Author Information
1. 宁波市疾病预防控制中心传染病防制所 职业与环境卫生所 315010
- Keywords:
COVID-19;
Close contacts;
Epidemiological characteristics;
Infection rate
- From:
Chinese Journal of Epidemiology
2020;41(5):667-671
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To estimate the infection rate of close contacts of COVID-19 cases, and to evaluate the risk of COVID-19 under different exposure conditions.Methods:A prospective study was used to conduct continuous quarantine medical observations of close contacts of people infected with COVID-19, collect epidemiological, clinical manifestations, and laboratory test data to estimate the infection rate of close contacts under different exposures.Results:The epidemiological curve of COVID-19 in Ningbo showed persistent human-to-human characteristics. A total of 2 147 close contacts were tracked and investigated. The total infection rate was 6.15%. The infection rates of confirmed cases and positive contacts were 6.30% and 4.11%, respectively. The difference was not statistically significant ( P>0.05). Among close contacts of different relationships, friends/pilgrims (22.31%), family members (18.01%), and relatives (4.73%) have a higher infection rate, and close contacts of medical staff were not infected. Differences in infection rates among the close contacts were statistically significant ( P<0.005). Living with the case (13.26%), taking the same transportation (11.91%), and dining together (7.18%) are high risk factors for infection. Cross-infection in the hospital should not be ignored (1.94%). The median of incubation period is 5 days. Conclusion:The infection rate of close contacts of COVID-19 cases is high, and isolation medical observation measures should be implemented in strict accordance with the close contact management plan.