The report, led by CSU researcher Jude Bayham, focuses on “mobility patterns”—broad patterns of how Coloradans move from place to place—using the devices nearly everyone carries with them nearly all the time: cell phones.

The Colorado School of Public Health assembled the expert research group, which includes modeling scientists at ColoradoSPH and the University of Colorado School of Medicine at the CU Anschutz Medical Campus, as well as experts from the University of Colorado Boulder, University of Colorado Denver, and Colorado State University.

“On March 25, in the face of a global pandemic, Colorado Gov. Jared Polis ordered the state’s residents to stay home as much as possible to mitigate COVID-19’s spread,” said Jonathan Samet, dean and professor for the ColoradoSPH and head of the modeling group. “Some restrictions were eased on April 26, and by and large, the majority of Coloradans have heeded the message.”

Tracking reduced social contact

The “Colorado Model” team has been collaborating with the Colorado Department of Public Health and Environment since March to track the spread of COVID-19 throughout Colorado and assess how to control it. The team provides state officials with timely reports and projections that both inform policies, like mandatory social distancing, and assess how the disease may continue to spread under different scenarios. In their most recent epidemiological modeling report issued in April, the team estimated that state residents effectively reduced social contact by about 75% to 80% since being told to stay home.

The new mobility report supports that finding, using heavily aggregated, anonymized data from two companies to create estimates of Coloradans’ mobility patterns, broken down by regions, municipalities and counties.

“We are essentially devising metrics by which we can track trends in mobility over time, and ultimately, we are trying to link those trends back to disease transmission and social distancing parameters,” said Bayham, an assistant professor in the CSU Department of Agricultural and Resource Economics who specializes in pandemic modeling, and a member of the CSU Task Force on Colorado Food Supply. “We are keeping a careful eye on case rates and hospitalization data in an effort to stay ahead of mobility patterns that may lead to greater transmission.”