Country-wide mobility changes observed using mobile phone data during COVID-19 pandemic

TL;DR

This study uses anonymized mobile phone data to quantitatively analyze nationwide mobility changes in Austria during COVID-19 lockdown, revealing significant reductions in movement and structural shifts in mobility networks, with implications for epidemiological modeling.

Contribution

It introduces an efficient data aggregation pipeline and provides a comprehensive analysis of mobility changes across Austria during COVID-19 using near-real-time mobile data.

Findings

Over 80% reduction in commuters at Viennese metro stations

Almost doubled number of devices with small movement radius

Increased modularity and community detection in mobility networks

Abstract

In March 2020, the Austrian government introduced a widespread lock-down in response to the COVID-19 pandemic. Based on subjective impressions and anecdotal evidence, Austrian public and private life came to a sudden halt. Here we assess the effect of the lock-down quantitatively for all regions in Austria and present an analysis of daily changes of human mobility throughout Austria using near-real-time anonymized mobile phone data. We describe an efficient data aggregation pipeline and analyze the mobility by quantifying mobile-phone traffic at specific point of interest (POI), analyzing individual trajectories and investigating the cluster structure of the origin-destination graph. We found a reduction of commuters at Viennese metro stations of over 80\% and the number of devices with a radius of gyration of less than 500 m almost doubled. The results of studying crowd-movement behavior highlight considerable changes in the structure of mobility networks, revealed by a higher modularity and an increase from 12 to 20 detected communities. We demonstrate the relevance of mobility data for epidemiological studies by showing a significant correlation of the outflow from the town of Ischgl (an early COVID-19 hotspot) and the reported COVID-19 cases with an 8-day time lag. This research indicates that mobile phone usage data permits the moment-by-moment quantification of mobility behavior for a whole country. We emphasize the need to improve the availability of such data in anonymized form to empower rapid response to combat COVID-19 and future pandemics.