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Mapping the COVID-19 Pandemic, Day by Day and Town by Town

April 30, 2020
by Robert Forman

A tab on the Yale website devoted to the COVID-19 pandemic is aptly labeled “innovation.” It leads readers to “Mapping COVID Data,” a repository of interactive maps that demonstrate the growth—and devastation—of the current pandemic. Created by people at Yale who are experts on turning raw data into compelling, informative geographic displays, the maps capture the viewer’s eye while making aspects of the pandemic clearer than sets of data or verbal descriptions ever could.

“We start with a question and then we say, ‘Can we answer it with a map?’” says Mike Friscia, lead technical architect for Yale School of Medicine’s Office of Communications, which built and maintains the COVID-19 site. “The goal is to produce maps that are useful for the public and the community, and, if we can get there, something that would be useful for organizations not just at Yale but throughout the state,” adds Mark Albis, a technical lead at the medical school.

The march of the virus through Connecticut day by day since March 21, as measured by confirmed cases, is one of the more compelling displays. “I was looking at the Connecticut county-level data,” says TC Chakraborty, a PhD candidate who works as a geospatial consultant for Yale’s Marx Science and Social Science Library, which has been home base for the mapping project. “And over time, even though Boston had its own cases, you could see the spread of the disease through Connecticut from west to east.” Now all visitors to the site can see that, town by Connecticut town.

There is even a map that estimates the probable number of infections in areas as small as 100 meters by 100 meters, less than the size of two football fields. Chakraborty emphasizes that it is just an estimate based on how much of a town’s population lives in each of those areas and the total number of confirmed cases in that town. “But having that kind of information at that scale,” he says, “is useful for people who are trying to decide where they should go and what they should do to minimize their risk of being exposed to the disease.”

Other maps on the site show national and international infection trends, including a map using United States Census data to estimate child care demand across the country for people who are considered essential workers.

Overall guidance for the project comes from a scholar who is considered the father of map algebra, the mathematics behind the synthesis of geographic data. Dana Tomlin, PhD, professor (adjunct) at Yale School of Forestry & Environmental Studies, says charting the movement of COVID-19 infection patterns is comparable to rigorously analyzing changes in the weather, and at least as important. He says this project is already growing beyond its initial function, which was oriented toward graphics for a general audience. “We now find ourselves orienting more toward analytics for a more specialized audience,” he says, “and logistics for a near future in which all of our daily activities—routine or otherwise—can benefit from a greater awareness of what is going on around us.”

Future additions could involve special attention to the so-called Acela corridor from Boston to Washington, with which Connecticut is so closely connected and whose prospects for ultimate economic revival are so intertwined. Jill Kelly, PhD, a lecturer at Yale School of Public Health, is working with Tomlin on two additional ideas. “Dana has been doing some work on where testing centers in Connecticut are located, compared to where the population is located,” Kelly explains. “That would give you an indicator of where you need a second testing center, for example, or to increase capacity at an existing center.” She also is looking into ways to explain higher-than-expected infection rates in certain rural Connecticut towns. “What I want to try is to overlay nursing homes and prisons on hotspots,” Kelly says.

The team has also solicited ideas from the Yale community, which it is now evaluating. Miriam Olivares, GISP, a geographic information systems librarian at Marx Library who brought the team together, says all involved have shown a remarkable spirit as they do their part to crush the pandemic. “The amazing thing is, despite the urgency of the matter and the overwhelming research overload Yale members have due to the pandemic, we have received several proposals,” she says. “It seems everybody is on the same boat trying to help.”

Contributors to the mapping project also include Anju Meenattoor, technical lead at Yale School of Medicine (YSM), and software developer Andrei Gulidov and data scientist Kiryl Lepchankou of the YSM Office of Communications technology team’s offshore development partners at iTechArt.

Submitted by Robert Forman on April 30, 2020