Center for Health Informatics Computing and Statistics, Lancaster Medical School, Lancaster University, Lancaster, UK.
Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.
BMC Infect Dis. 2021 Mar 22;21(1):291. doi: 10.1186/s12879-021-05922-1.
Information on the etiology and age-specific burden of respiratory viral infections among school-aged children remains limited. Though school aged children are often recognized as driving the transmission of influenza as well as other respiratory viruses, little detailed information is available on the distribution of respiratory infections among children of different ages within this group. Factors other than age including gender and time spent in school may also be important in determining risk of infection but have been little studied in this age group.
We conducted a cohort study to determine the etiology of influenza like illness (ILI) among 2519 K-12 students during the 2012-13 influenza season. We obtained nasal swabs from students with ILI-related absences. Generalized linear mixed-effect regressions determined associations of outcomes, including ILI and laboratory-confirmed respiratory virus infection, with school grade and other covariates.
Overall, 459 swabs were obtained from 552 ILI-related absences. Respiratory viruses were found in 292 (63.6%) samples. Influenza was found in 189 (41.2%) samples. With influenza B found in 134 (70.9%). Rates of influenza B were significantly higher in grades 1 (10.1, 95% CI 6.8-14.4%), 2 (9.7, 6.6-13.6%), 3 (9.3, 6.3-13.2%), and 4 (9.9, 6.8-13.8%) than in kindergarteners (3.2, 1.5-6.0%). After accounting for grade, sex and self-reported vaccination status, influenza B infection risk was lower among kindergarteners in half-day programs compared to kindergarteners in full-day programs (OR = 0.19; 95% CI 0.08-0.45).
ILI and influenza infection is concentrated in younger schoolchildren. Reduced infection by respiratory viruses is associated with a truncated school day for kindergarteners but this finding requires further investigation in other grades and populations.
关于学龄儿童呼吸道病毒感染的病因和年龄特异性负担的信息仍然有限。尽管学龄儿童通常被认为是流感以及其他呼吸道病毒传播的驱动力，但关于该人群中不同年龄儿童呼吸道感染分布的详细信息很少。除年龄以外的其他因素，包括性别和在校时间，也可能对感染风险有重要影响，但在该年龄组中研究甚少。
我们进行了一项队列研究，以确定 2012-13 流感季节 2519 名 K-12 学生中流感样疾病（ILI）的病因。我们从有 ILI 相关缺勤的学生中采集鼻拭子。广义线性混合效应回归确定了结局（包括 ILI 和实验室确诊的呼吸道病毒感染）与学校年级和其他协变量的关联。
总体而言，从 552 例 ILI 相关缺勤中获得了 459 个拭子。在 292 个（63.6%）样本中发现了呼吸道病毒。在 189 个（41.2%）样本中发现了流感。乙型流感占 134 例（70.9%）。1 年级（10.1，95%CI 6.8-14.4%）、2 年级（9.7，6.6-13.6%）、3 年级（9.3，6.3-13.2%）和 4 年级（9.9，6.8-13.8%）的乙型流感发生率明显高于幼儿园（3.2，1.5-6.0%）。在考虑年级、性别和自我报告的疫苗接种状况后，与全日制幼儿园相比，半日制幼儿园的乙型流感感染风险较低（OR=0.19；95%CI 0.08-0.45）。
ILI 和流感感染集中在年幼的学龄儿童中。呼吸道病毒感染减少与幼儿园日托时间缩短有关，但这一发现需要在其他年级和人群中进一步研究。
