Each year, healthcare settings are confronted by outbreaks caused by influenza and infected patients produce aerosols making this route a potential issue during outbreaks. This study was conducted in an Eastern Canadian hospital during three confirmed influenza outbreaks. Air was sampled in the rooms of infected patients using a liquid cyclone sampler and an electret dry filter sampler, two high flowrate aerosol samplers. During the third outbreak, a water-based condensation sampler, which has a low flowrate, was also used for aerosol sampling. Influenza RNA concentrations were observed at up to 1.05 $\times$ 10⁵ (electret dry filter sampler), 1.99 $\times$ 10⁵ (liquid cyclone sampler) and 3.02 $\times$ 10⁵ (water-based condensation sampler) genomes/m³, but varied greatly between outbreaks. During the first outbreak, 14 positive samples were recovered with RNA concentrations between 6.66 × 10² and 1.99 × 10⁵ genomes/m³. For the second outbreak, 18 samples were positive, but lower concentrations were detected, from 1.53 × 10¹ to 5.97 × 10² genomes/m³. Three positive samples with concentrations between 6.09 × 10⁴ and 3.02 × 10⁵ genomes/m³ were recovered during the third outbreak. This study provides crucial information regarding the differences in airborne influenza viruses during three different outbreaks that took place in the same hospital. Comparisons of airborne virus concentrations in other hospital or long-term care settings would contribute to a better understanding of the role that air can play in influenza outbreaks.

每年，医疗机构都会面临由流感引起的暴发，受感染的患者会产生气溶胶，使这条途径成为暴发期间的潜在问题。这项研究是在加拿大东部的一家医院在三场确诊的流感爆发期间进行的。使用液体旋风采样器和驻极​​体干式过滤器采样器（两个高流速气溶胶采样器）对感染患者房间的空气进行采样。在第三次爆发期间，还使用了流速较低的水基冷凝采样器进行气溶胶采样。观察到的流感 RNA 浓度高达 1.05$\times$10 ⁵（驻极体干式过滤采样器），1.99$\times$10 ⁵（液体旋流取样器）和 3.02$\times$10 ⁵（水基冷凝采样器）基因组/m ³，但在爆发之间差异很大。在第一次爆发期间，回收了 14 个阳性样本，其 RNA 浓度介于 6.66 × 10 ²和 1.99 × 10 ⁵基因组/m ^{3 之间}。对于第二次爆发，18 个样本呈阳性，但检测到的浓度较低，从 1.53 × 10 ¹到 5.97 × 10 ²基因组/m ³。三个阳性样本，浓度介于 6.09 × 10 ⁴和 3.02 × 10 ⁵基因组/m ^{3 之间}在第三次爆发期间恢复。这项研究提供了关于在同一家医院发生的三种不同爆发期间空气传播的流感病毒差异的重要信息。比较其他医院或长期护理机构中空气传播的病毒浓度将有助于更好地了解空气在流感爆发中的作用。