Spatial mobility patterns and COVID-19 incidence: A regional analysis of the second wave in the Netherlands

A key policy measure introduced by governments worldwide at the beginning of the coronavirus disease 2019 (COVID-19) pandemic was to restrict travel, highlighting the importance of people's mobility as one of the key contributors to spreading severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, there was little consistency regarding the geographical scale or the severity of these measures. Little use was made of commuting and travel data to inform decisions on when, where and at what level restrictions should be applied. We aim to contribute to regional policy by providing evidence that could be used to inform future policy debates on the most effective travel restrictions to impose during a pandemic. We present an analysis of the impact of mobility between municipalities on COVID-19 incidence in the Netherlands. We used multiple linear regression models and geographical information systems to gain insight into the association between mobility-related factors and demographic, socio-economic and geographical factors with COVID-19 incidence in municipalities. Our results indicate that spatial mobility patterns, when combined with COVID-19 incidence in municipalities of origin, were associated with increased COVID-19 incidence in municipalities of destination. In addition, various regional characteristics were associated with municipal incidence. By conducting our analyses over three different periods, we highlight the importance of time for COVID-19 incidence. In the light of ongoing mitigation measures (and possible future events), spatial mobility patterns should be a key factor in exploring regional mobility restrictions as an alternative for national lockdowns.