病毒学报

目的 利用气溶胶发生器模拟传染源，系统评估通风状态、采样距离及病毒发射时长对甲型流感病毒空气传播过程中病毒载量的影响，并通过Gamma广义线性模型和多重线性回归分别对影响悬浮病毒和沉降病毒各因素的相对贡献进行定量分析，明确悬浮病毒与沉降病毒的传播特征差异。方法 在温度20℃～23℃、相对湿度53%～56%的空气传播设备中，利用气溶胶发生器发射含A(H1N1)pdm09流感病毒的感染性呼吸颗粒（Infectious respiratory particles,IRPs），设置不同通风状态（开启/关闭）、发射时长（5 min、10 min、15 min）及采样距离（10～200cm），采集空气悬浮病毒和设备内表面沉降病毒样本，采用qPCR检测样本中病毒RNA拷贝数，对病毒RNA拷贝数进行单因素及多重线性回归分析。结果 悬浮病毒载量影响因素分析显示，开启通风（Exp(B)=0.773,P=0.001）和增加采样距离（Exp(B)=0.996,P<0.001）可显著降低悬浮病毒与沉降病毒载量。通风量每增加1个单位，病毒RNA拷贝数对数平均降低22.7%；采样距离每增加1个单位，病毒RNA拷贝数对数平均降低0.4%。而发射时长在模型中未呈显著关联（P=0.121）。发射时长每增加1个单位，病毒RNA拷贝数对数平均增加0.015%。对沉降病毒载量影响因素分析结果表明，通风（P<0.001）、发射时长（P=0.011）及采样距离（P<0.001）均与沉降病毒载量显著相关。通风与病毒RNA拷贝数呈负相关，通风每增加1个单位，病毒RNA拷贝数对数平均降低1.001；发射时长与病毒RNA拷贝数呈正相关，发射时长每增加1个单位，病毒RNA拷贝数对数平均增加0.060；采样距离与病毒RNA拷贝数呈负相关，采样距离每增加1个单位，病毒RNA拷贝数对数降低0.010。结论 本研究利用气溶胶发生器模拟实验验证，通风和采样距离是影响流感病毒空气传播风险的关键环境因素。加强通风和保持社交距离可有效降低流感病毒空气传播风险，为流感等呼吸道传染病的空气传播风险评估与防控策略提供了科学数据依据。

Objective To simulate the source of infection using an aerosol generator, and systematically evaluate the effects of ventilation conditions, sampling distance, and viral emission duration on viral load during the airborne transmission of influenza A virus. The relative contributions of factors affecting airborne and settled viruses were quantitatively analyzed using Gamma generalized linear models and multiple linear regression, respectively, to clarify the differences in transmission characteristics between airborne and settled viruses. Methods In an airborne transmission chamber maintained at a temperature of 20℃-23℃ and a relative humidity of 53%-56%, infectious respiratory particles(IRPs) containing influenza A(H1N1)pdm09 virus were generated using an aerosol generator. Different ventilation conditions(on/off), emission durations(5 min, 10 min, and 15 min), and sampling distances(10～200 cm) were set. Samples of airborne suspended viruses and surface-settled viruses were collected, and viral RNA copy numbers were determined by qPCR. Univariate and multiple linear regression analyses were performed on viral RNA copy numbers. Results For airborne viral load, turning ventilation on(Exp(B) = 0.773, P = 0.001) and increasing sampling distance(Exp(B) = 0.996, P < 0.001) significantly reduced airborne viral load. Each 1-unit increase in ventilation was associated with a mean 22.7% reduction in log-transformed viral RNA copies; each 1-unit increase in sampling distance was associated with a mean 0.4% reduction in log-transformed viral RNA copies. Emission duration showed no significant association in the model(P = 0.121), with each 1-unit increase corresponding to a mean increase of 0.015% in log-transformed viral RNA copies. For settled viral load, ventilation(P < 0.001), emission duration(P = 0.011), and sampling distance(P < 0.001) were all significantly associated with viral load. Ventilation was negatively correlated with viral RNA copies; each 1-unit increase in ventilation corresponded to a mean reduction of 1.001 in log-transformed copies. Emission duration was positively correlated: each 1-unit increase corresponded to a mean increase of 0.060 in log-transformed viral RNA copies. Sampling distance was negatively correlated with viral RNA copies; each 1-unit increase in sampling distance corresponded to a mean reduction of 0.010 in log-transformed viral RNA copies. Conclusion This simulation study using an aerosol generator demonstrates that ventilation and sampling distance are key environmental factors affecting the airborne transmission risk of influenza virus. Enhanced ventilation and maintaining appropriate distance can effectively reduce the risk of airborne influenza transmission, providing scientific data for risk assessment and prevention and control strategies for airborne transmission of respiratory infectious diseases such as influenza.