Kraut Roni Y, Snedeker Kate G, Babenko Oksana, Honish Lance
Department of Family Medicine, University of Alberta, Edmonton, AB, Canada T6G 2T4.
Department of Public Health Sciences, University of Alberta, Edmonton, AB, Canada T6G 1C9; Surveillance and Reporting, Alberta Health Services, Edmonton, AB, Canada T2W 3N2.
Can J Infect Dis Med Microbiol. 2017;2017:9258140. doi: 10.1155/2017/9258140. Epub 2017 Jan 12.
Factors affecting the seasonal distribution of norovirus outbreaks are not well understood. This study examined whether grade school settings at the start of the school year may be a factor. We searched Ovid Medline from January 2002 to June 2014 for studies that provided all reported norovirus outbreaks in a developed country by month for a minimum of three years. Historical school years were obtained from verifiable sources. The start of the norovirus seasonal outbreak peak and peak outbreak month were determined for each study and compared to the start month of school. Northern hemisphere and southern hemisphere countries had a different norovirus seasonality and different school year structures (traditional compared to year round). In the two studies that provided outbreaks by age, outbreaks among children started several months before outbreaks in the adult population. The median number of months between school start and start of the seasonal outbreak peak was two months (interquartile range [IQR] = 2.0-3.0), while the median number of months between school start and peak outbreak month was four months (IQR = 3.0-4.0). These findings suggest the possibility the school setting at the start of the school year may be a factor in the seasonality of norovirus.
影响诺如病毒暴发季节性分布的因素尚未得到充分了解。本研究调查了学年开始时的小学环境是否可能是一个因素。我们检索了2002年1月至2014年6月的Ovid Medline数据库，查找那些至少提供了一个发达国家三年中每月所有报告的诺如病毒暴发情况的研究。历史学年信息来自可核实的来源。确定每项研究中诺如病毒季节性暴发高峰的开始时间和暴发高峰月份，并与开学月份进行比较。北半球和南半球国家的诺如病毒季节性不同，学年结构也不同（传统学年与全年制学年）。在两项按年龄提供暴发情况的研究中，儿童中的暴发比成人中的暴发提前几个月开始。开学至季节性暴发高峰开始之间的月数中位数为2个月（四分位间距[IQR]=2.0-3.0），而开学至暴发高峰月份之间的月数中位数为4个月（IQR=3.0-4.0）。这些发现表明，学年开始时的学校环境可能是诺如病毒季节性的一个因素。
