湖南省156例有确切暴露时间的新冠肺炎病例潜伏期的研究

目的 分析156例有确切暴露时间的COVID-19聚集性病例的潜伏期,为其防控策略和措施提供依据。 方法 收集2020年1—2月湖南省报告的COVID-19聚集性病例资料,根据病例暴露时间和发病时间,采用中位数方法估算COVID-19的潜伏期,采用秩和检验比较不同暴露方式潜伏期的差异,描述3例超长潜伏期病例信息。 结果 156例有确切暴露时间的确诊病例平均潜伏期7.0 d,四分位数间距Q为5.0 d;53例单源一次暴露病例平均潜伏期6.0 d,四分位数间距Q为5.0 d;103例多次暴露病例平均潜伏期7.5 d,四分位数间距Q为5.0 d。同车、近距离交谈等暴露方式潜伏期(5.0 d)短于聚餐暴露(8.0 d)(Z=-2.589,P=0.01),家庭暴露最短潜伏期(2.0 d)短于非家庭暴露最短潜伏期(5.5 d)(Z=-3.335,P=0.001)。3例病例潜伏期超过14 d,分别为16、16、17 d。 结论 COVID-19平均潜伏期为7.0 d,家庭暴露导致该病传播风险更高,存在超长潜伏期病例。早发现、早隔离病例和密切接触者,是防止疫情进一步扩散的重要手段。

Incubation periods of 156 COVID-19 cases with exact exposure time in Hunan Province

Objective To analyze the incubation periods of 156 COVID-19 cluster cases with exact exposure time, and to provide a basis for COVID-19 prevention and control strategies and measures. Methods Data concerning COVID-19 cluster cases reported in Hunan Province from January to February 2020 were collected. According to the cases' exposure and onset time, the incubation periods of the COVID-19 cases were estimated by median method. Differences in the incubation periods of different exposure modes were compared by rank-sum test, and the information about 3 cases with extra-long incubation periods was described. Results The average incubation period for 156 confirmed cases with exact exposure time was 7.0 days, and theinterquartile interval Q was 5.0 days. The average incubation period for 53 cases with single source exposure was 6.0 days, with the interquartile interval Q being 5.0 days. The average incubation period for 103 cases with multiple exposure was 7.5 days, with the interquartile interval Q being 5.0 days. The incubation period (5.0 days) of sharing a same car and close talk exposure was shorter than that of dinner exposure (8.0 days) (Z=-2.589,P=0.01). The shortest incubation period of family exposure (2.0 days) was shorter than that of non-family exposure (5.5 days) (Z=-3.335, P=0.001). The incubation periods of 3 cases exceeded 14 days, which were 16, 16 and 17 days, respectively. Conclusion The average incubation period for the COVID-19 cases was 7.0 days. The risk of COVID-19 transmission due to family exposure was higher, and there were cases with extra-long incubation period. Early detection and isolation of the cases and close contacts are important means to prevent further spread of the epidemic.