Urban Rail Transportation and SARS-Cov-2 Infections: An Ecological Study in the Lisbon Metropolitan Area

• Published in: Frontiers in public health 2021-02, Vol.9, p.611565-611565
• Main Authors: Severo, Milton, Ribeiro, Ana Isabel, Lucas, Raquel, Leão, Teresa, Barros, Henrique
• Format: Article
• Language: English
• Subjects: coronavirus (2019-nCoV); COVID-19 - epidemiology; COVID-19 - transmission; disease transmission; Humans; Portugal - epidemiology; Public Health; Railroads; SARS-CoV-2; transport policy; urban health
• ISSN: 2296-2565; 2296-2565
• DOI: 10.3389/fpubh.2021.611565

The large number of passengers, limited space and shared surfaces can transform public transportation into a hub of epidemic spread. This study was conducted to investigate whether proximity to railway stations, a proxy for utilization, was associated with higher rates of SARS-CoV-2 infection across small-areas of the Lisbon Metropolitan Area (Portugal). The number of SARS-CoV-2 confirmed infections from March 2 until July 5, 2020 at the parish-level was obtained from the National Epidemiological Surveillance System. A Geographic Information System was used to estimate proximity to railway stations of the six railway lines operating in the area. A quasi- generalized linear regression model was fitted to estimate the relative risks (RR) and corresponding 95% confidence intervals (95%CI). Between May 2 and July 5, 2020, there were a total of 17,168 SARS-CoV-2 infections in the Lisbon Metropolitan Area, with wide disparities between parishes. Overall, parishes near any of the railway stations of the line presented significantly higher SARS-CoV-2 infection rates ( = 1.42, 95%CI 1.16, 1.75) compared to parishes located farther away from railway stations, while the opposite was observed for parishes near other railway stations ( and lines), where infection rates were significantly lower than those observed in parishes located farther away from railway stations ( = 0.66, 95%CI 0.50, 0.87). The associations varied according to the stage of the epidemic and to the mitigation measures enforced. Regression results also revealed an increasing influence of socioeconomic deprivation on SARS-CoV-2 infections. No consistent association between proximity to railway stations and SARS-CoV-2 infection rates in the most affected metropolitan area of Portugal was observed, suggesting that other factors (e.g., socioeconomic deprivation) may play a more prominent role in the epidemic dynamics.