Particularly in rural settings, there has been little research regarding the health impacts of fine particulate matter (PM2.5) during the wildfire season smoke exposure period on respiratory diseases, such as influenza, and their associated outbreaks months later. We examined the delayed effects of PM2.5 concentrations for the short-lag (1-4 weeks prior) and the long-lag (during the prior wildfire season months) on the following winter influenza season in Montana, a mountainous state in the western United States. We created gridded maps of surface PM2.5 for the state of Montana from 2009 to 2018 using spatial regression models fit with station observations and Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical thickness data. We used a seasonal quasi-Poisson model with generalized estimating equations to estimate weekly, county-specific, influenza counts for Montana, associated with delayed PM2.5 concentration periods (short-lag and long-lag effects), adjusted for temperature and seasonal trend. We did not detect an acute, short-lag PM2.5 effect nor short-lag temperature effect on influenza in Montana. Higher daily average PM2.5 concentrations during the wildfire season was positively associated with increased influenza in the following winter influenza season (expected 16% or 22% increase in influenza rate per 1 μg/m3 increase in average daily summer PM2.5 based on two analyses, p = 0.04 or 0.008). This is one of the first observations of a relationship between PM2.5 during wildfire season and influenza months later.

中文翻译：

---

野火季节颗粒物对美国西部山区随后流感季节的延迟影响。


特别是在农村地区，关于野火季节烟雾暴露期间细颗粒物 (PM2.5) 对流感等呼吸道疾病及其几个月后相关爆发的健康影响的研究很少。我们研究了蒙大拿州（西部山区的一个州）下一个冬季流感季节期间 PM2.5 浓度的短滞后（1-4 周前）和长滞后（前野火季节月份期间）的延迟影响。美国。我们使用与站点观测和中分辨率成像光谱仪 (MODIS) 气溶胶光学厚度数据相匹配的空间回归模型，创建了 2009 年至 2018 年蒙大拿州表面 PM2.5 的网格地图。我们使用具有广义估计方程的季节性准泊松模型来估计蒙大拿州每周特定县的流感计数，该计数与延迟的 PM2.5 浓度周期（短滞后和长滞后效应）相关，并根据温度和季节性趋势进行了调整。我们没有检测到蒙大拿州流感对 PM2.5 的急性、短滞后效应或短滞后温度效应。野火季节期间较高的日均 PM2.5 浓度与接下来的冬季流感季节的流感增加呈正相关（根据两项研究，夏季 PM2.5 日均浓度每增加 1 μg/m3，预计流感发病率将增加 16% 或 22%）分析，p = 0.04 或 0.008）。这是野火季节 PM2.5 与几个月后流感之间关系的首次观察结果之一。