Liu Yanhui, Chen Zhitao, Zhang Meiqi, Wang Dedong, Ma Mengmeng, Qin Pengzhe, Luo Lei, Wu Di
Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong, China.
Department of Public Health and Preventive Medicine, Jinan University, Guangzhou, China.
BMJ Open. 2025 Jun 23;15(6):e096341. doi: 10.1136/bmjopen-2024-096341.
To examine whether influenza transmission risk decreased during summer and winter vacations and increased after vacations and statutory holiday.
An ecological study.
Guangzhou, Guangdong Province of China.
A total of 458 343 influenza cases in school-aged children were included, including 160 067 (35.05%) in kindergarten, 223 817 (48.83%) in primary school, 50 053 (10.92%) in middle school and 23 801 (5.19%) in high school.
Data on influenza cases were obtained from the Notifiable Infectious Disease Surveillance System operated by Guangzhou Centre for Disease Control and Prevention. Influenza incidence rate ratio (IRR) by negative binomial regression model was used to analyse the influenza risk of school-age children during/after vacation to before/during breaks.
In all four groups, there was significantly lower incidence of influenza during winter and summer vacations compared with the 4 weeks preceding vacations. Compared with the 2 weeks preceding return, kindergarten students experienced the highest influenza risk in the third week after summer vacation (IRR=3.40, 95% CI 2.43to 4.79). Primary school students had the highest risk in the fourth week after winter vacation (IRR=9.59, 95% CI 6.71 to 13.87). Middle school students had the highest risk in the fourth week after summer (IRR=11.60, 95% CI 6.17 to 22.62). High school students also experienced the highest risk in the fourth week following summer (IRR=17.96, 95% CI 8.10 to 42.05). Despite the risk of influenza increasing after returning to school, it remained lower compared with before vacations and holidays.
Due to changes in contact patterns, influenza incidence was high towards the end of term, significantly decreased during vacations and started to rise on returning to school, peaking in the third or fourth week. These findings suggested using holiday periods strategically to promote influenza vaccination and implementing enhanced non-pharmaceutical interventions on students returning to school.
研究寒暑假及法定节假日期间流感传播风险是否降低，假期结束后是否增加。
一项生态学研究。
中国广东省广州市。
纳入了458343例学龄儿童流感病例，其中幼儿园儿童160067例（35.05%），小学生223817例（48.83%），中学生50053例（10.92%），高中生23801例（5.19%）。
流感病例数据来自广州市疾病预防控制中心运营的法定传染病监测系统。采用负二项回归模型计算流感发病率比（IRR），以分析学龄儿童在假期期间/结束后与假期前/期间相比的流感风险。
在所有四组中，寒暑假期间的流感发病率均显著低于假期前4周。与返校前2周相比，幼儿园儿童在暑假后第三周流感风险最高（IRR=3.40，95%CI 2.43至4.79）。小学生在寒假后第四周风险最高（IRR=9.59，95%CI 6.71至13.87）。中学生在暑假后第四周风险最高（IRR=11.60，95%CI 6.17至22.62）。高中生在暑假后第四周风险也最高（IRR=17.96，95%CI 8.10至42.05）。尽管返校后流感风险增加，但仍低于假期和节假日之前。
由于接触模式的变化，学期末流感发病率较高，假期期间显著下降，返校后开始上升，在第三或第四周达到峰值。这些发现建议战略性地利用假期来推广流感疫苗接种，并对返校学生实施强化的非药物干预措施。
