Airborne diseases, including COVID-19, raise the question of transmission risk in public transportation systems. However, quantitative analysis of the effectiveness of transmission risk mitigation methods in public transportation is lacking. The paper develops a transmission risk modeling framework based on the Wells-Riley model using as inputs transit operating characteristics, schedule, Origin-Destination (OD) demand, and virus characteristics. The model is sensitive to various factors that operators can control, as well as external factors that may be subject of broader policy decisions (e.g. mask wearing). The model is utilized to assess transmission risk as a function of OD flows, planned operations, and factors such as mask-wearing, ventilation, and infection rates. Using actual data from the Massachusetts Bay Transportation Authority (MBTA) Red Line, the paper explores the transmission risk under different infection rate scenarios, both in magnitude and spatial characteristics. The paper assesses the combined impact from viral load related factors and passenger load factors. Increasing frequency can mitigate transmission risk, but cannot fully compensate for increases in infection rates. Imbalanced passenger distribution on different cars of a train is shown to increase the overall system-wide infection probability. Spatial infection rate patterns should also be taken into account during policymaking as it is shown to impact transmission risk. For lines with branches, demand distribution among the branches is important and headway allocation adjustment among branches to balance the load on trains to different branches can help reduce risk.
翻译:包括COVID-19在内的空气传播疾病提出了公共交通系统传播风险的问题,然而,缺乏对公共交通中传播风险缓解方法有效性的定量分析,但缺乏对公共交通中传播风险缓解方法有效性的定量分析,该文件根据Wells-Riley模型开发了一个传输风险模型框架,该模型以Wells-Riley模型为基础,作为输入中转操作特点、时间表、原宿需求以及病毒特性;该模型对操作者能够控制的各种因素以及可能作出更广泛政策决定的外部因素(例如戴面罩)十分敏感;该模型用于评估传播风险,作为组织流动、计划操作以及遮罩、通风和感染率等因素的函数;利用马萨诸塞湾运输管理局(MBTA)红线的实际数据,该文件探索不同感染率情景下的传播风险,包括规模和空间特点;该模型评估了病毒负荷相关因素和乘客负荷因素的综合影响;增加频率可以减轻传播风险,但不能充分补偿感染率的上升;该模型用于评估不同火车车辆的均衡乘客分配,以提高整个系统的风险、通风和感染率分配。