新冠肺炎病毒颗粒在空调大巴中的传播与乘客感染风险

Transmission of COVID-19 viral particles and the risk of infection among passengers in air-conditioned buses

新型冠状病毒肺炎(COVID-19)存在气溶胶传播的可能性。该文选择了一例发生在湖南省空调大巴中的新冠肺炎传染案例,建立数值模型开展计算,分析了含新冠肺炎病毒的液滴和气溶胶的扩散输运过程,研究了空调排风模式、颗粒粒径、传染源位置等因素对于新冠肺炎病毒在空调大巴中传播规律的影响,并针对所有乘客的感染风险进行了定量评估,将结果与实际感染情况进行了对比。新冠肺炎感染者呼出的病毒颗粒有较高的比例沉积在大巴内部壁面与座椅表面。粒径和排风口位置会影响气溶胶扩散规律。小粒径含病毒气溶胶在空气中悬浮的时间长、扩散距离远,带给远处乘客的风险较高。基于研究结果,提出了降低空调大巴中新冠肺炎传播风险的建议。

Aerosol transmission of the corona virus disease 2019(COVID-19)is possible.This study analyzed COVID-19 transmission in an air-conditioned bus in Hunan Province,China.A numerical model was used to predict the transport of droplets and aerosols containing the COVID-19 virus for various air conditioning modes,particle sizes,and source locations.The results were used for quantitative evaluations of the infection risks for all passengers with comparisons to the actual transmission rate.A high proportion of exhaled viral particles from COVID-19 infected people were deposited on the inner wall of the bus and the seat surface.Changing the particle sizes and the outlet locations leads to different aerosol diffusion paths.Small aerosols containing the virus can remain suspended in the air for prolonged periods of time and become widely spread,so these pose a higher risk to passengers seated far from the source.The results are used to develop suggestions for reducing the COVID-19 infection risk in air-conditioned buses.