Study on acquired infection of patients in waiting space of fever clinic

Abstract

Since the COVID-19 outbreak, high numbers of patients with respiratory symptoms flock to fever clinic, cause overcrowding. Due to relatively densely populated space and the existing ventilation strategy, lead to space environment bearing capacity lose efficacy. The patients in waiting space are faced a high risk of cross infection. Thus, it must be strictly controlling the personnel density and fresh air dilution level, prevent SARS-COV-2 transmission though aerosols. This study takes the fever clinic of 3A Grade Hospital case, based on the monitoring results of CO2 concentration and the transport of exhaled pathogenic aerosols, predict the waiting patient’s cross infection risk in crowded space. Computational fluid dynamics simulations and agent social force behaviour model were used. When the number of fever clinic reaches the upper limit of theoretical capacity, under the three ventilation types, average exposure risk in different areas of waiting space were studied. Results show that when the infector is located at the front of the waiting corridor (upwind direction of natural ventilation), when there is only natural ventilation, the difference of average intake fraction in the three areas of waiting space is small, that is, the correlation between distance and exposure is small. Our results also show that when ceiling air conditioner ventilation and natural ventilation are coupled, the dilution effect is significantly lower than that of natural ventilation in the front and rear area, and higher than only run mechanical ventilation.