Impact of COVID-19 Pandemic on Spatial Separation of New and Existing Residents: Case Study of Tsukuba City in Greater Tokyo Area.

For balancing the improvement of social capital through mutual interaction among residents and measures against infectious diseases, municipalities must understand where their residents interact with each other during epidemics. By distinguishing between new and existing residents based on the average age of the houses in their residential areas, we measured the degree of separation between them at various locations and facilities in the Tsukuba City in the Greater Tokyo Area during the daytime based on smartphone location information. We also investigated separation by visitors' residential savings and income class and their age and gender in each location. Separation was observed in almost all the public places in Tsukuba City, even before the COVID-19 outbreak. During the outbreak, many public places and facilities were visited by fewer people, and yet their separation increased. On the other hand, separation lessened in parks, increasing opportunities for residents to interact. Even after the outbreak began, lower separation environments remained in places where food courts and department stores were located compared to other places. In the post-outbreak period, separation returned to its normal level.