Yu Meng, Chen Zhenhua
City and Regional Planning, The Ohio State University, Columbus, OH, 43210, USA.
J Air Transp Manag. 2021 Oct;97:102140. doi: 10.1016/j.jairtraman.2021.102140. Epub 2021 Sep 8.
The outbreak of the COVID-19 pandemic has a lasting and unprecedented negative impact on the global aviation industry. While countries such as China have successfully curbed the domestic outbreak of the virus with various restrictive and preventive measures, the challenge of avoiding imported cases remains. More importantly, it is still unclear to what extent these implemented aviation emergency responses have effectively mitigated the transmission risk of the virus. This paper provides an empirical assessment of aviation responses to the control of imported COVID-19 cases, with a focus on the following three strategies: the "circuit breaker" policy, the "negative Nucleic Acid testing (NAT)", and the "double negative tests" requirement. Non-recursive structural equation models (SEM) with latent variables were applied to detailed international flight data and individual epidemic survey data of Guangzhou, China, between May 1 and November 30, 2020. The results show that the "double negative tests" measure has a positive effect on eliminating the number of SARS-CoV-2 carriers, while the effects of single "circuit breaker" and its co-intervention with "negative NAT" are conterproductive. This study provides important implications to civil aviation agencies in regard to medium and long-term risk control of imported cases. Specifically, although the circuit breaker mechanism was designed to target on the risk control of imported COVID-19 cases, it may be more effective to carefully maintain a timely and reliable pre-boarding screening and testing to curb the number of imported cases.
新冠疫情的爆发对全球航空业产生了持久且前所未有的负面影响。尽管中国等国家通过各种限制和预防措施成功遏制了国内病毒的爆发，但避免输入性病例的挑战依然存在。更重要的是，目前仍不清楚这些已实施的航空应急措施在多大程度上有效降低了病毒的传播风险。本文对航空业应对输入性新冠病例控制措施进行了实证评估，重点关注以下三种策略：“熔断”政策、“核酸检测阴性（NAT）”以及“双阴性检测”要求。运用带有潜在变量的非递归结构方程模型（SEM），对中国广州2020年5月1日至11月30日期间详细的国际航班数据和个体疫情调查数据进行分析。结果表明，“双阴性检测”措施对减少新冠病毒携带者数量有积极作用，而单一“熔断”政策及其与“核酸检测阴性”的联合干预效果适得其反。本研究为民航机构在输入性病例的中长期风险控制方面提供了重要启示。具体而言，尽管熔断机制旨在针对输入性新冠病例的风险控制，但谨慎维持及时可靠的登机前筛查和检测可能对遏制输入性病例数量更为有效。
