AUTHOR=Severo Milton , Ribeiro Ana Isabel , Lucas Raquel , Leão Teresa , Barros Henrique 

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

JOURNAL=Frontiers in Public Health

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2021.611565

DOI=10.3389/fpubh.2021.611565

ISSN=2296-2565

ABSTRACT=<p><bold>Introduction:</bold> 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).</p><p><bold>Methods:</bold> 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-<italic>Poisson</italic> generalized linear regression model was fitted to estimate the relative risks (RR) and corresponding 95% confidence intervals (95%CI).</p><p><bold>Results:</bold> 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 <italic>Sintra</italic> line presented significantly higher SARS-CoV-2 infection rates (<italic>RR</italic> = 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 (<italic>Sado</italic> and <italic>Fertagus</italic> lines), where infection rates were significantly lower than those observed in parishes located farther away from railway stations (<italic>RR</italic> = 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.</p><p><bold>Conclusions:</bold> 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.</p>