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Mapping the COVID-19 Pandemic in Connecticut

Yale Medicine Magazine, 2021 Issue 166


Yale School of Medicine’s COVID-19 Mapping Initiative offers Connecticut residents different ways to visualize the pandemic’s impact on the state and town levels.

When you want to know the COVID-19 case numbers in New Haven, where do you look? What about other towns across Connecticut or states across the country? Many sites have been offering public data sets with this information, but if you want specific details like town-by-town case maps; estimates of child care demand for the children of workers in critical sectors; or population-specific case numbers, like those for correctional facilities, nursing homes, or schools, the Yale School of Medicine COVID-19 Mapping Initiative has become the place to turn.

The mapping project collects and creates maps that visualize the current state, spread, and impact of the coronavirus pandemic. Devised by CoReCT (COVID-19 Response Coordination Team), a collaborative group that coordinates Yale’s scientific, medical, and research response to COVID-19, the project provides context to raw data.

“Our goal in creating CoReCT was to break down silos and connect people across the university. The mapping initiative is a terrific example of how teamwork has led to innovative solutions,” said Nancy J. Brown, MD, the Jean and David W. Wallace Dean of Medicine and C.N.H. Long Professor of Medicine.

Forging Collaborations Beyond the Yale School of Medicine

Justin Fansler is the senior technology director for Yale School of Medicine who administers the site along with technical leads Mark Albis and Anju Meenattoor and Lead Technical Architect Michael Friscia. Fransler said, “We wanted to figure out how we could bring to bear the full resources of Yale to do something that would help humanity fight COVID-19.” While CoReCT is a much larger initiative that also facilitates clinical trials, resources, and funding, the mapping project is an important aspect of its mission.

In addition to unprecedented collaboration, the goal of Yale School of Medicine’s project has been to add value without replicating other mapping projects. Inspired by Johns Hopkins’ model, the Yale School of Medicine’s Office of Communications technology team decided to do something a little different. They put out a call across the university for unique maps, and received over 30 proposals from various schools, including Public Health, Management, Medicine, and Environment. Then the team picked a handful of maps that represented a cross-section of topics that provided utility and drew on available data sets.

Said Friscia, “The team was genuinely interested in making sure that we were doing something to try to help people.”

Utilizing Geospatial Resources to Address Challenges

Friscia reached out to Miriam Olivares, MSc, GISP, the geospatial librarian at the Marx Science and Social Science Library, who coordinates the Yale Library’s geospatial support services. She and Tirthankar (“TC”) Chakraborty, who completed his PhD at the Yale School of the Environment in 2021 and was a geospatial consultant to the library, provided geospatial instruction, expertise, and guidance during preliminary work on the project. Olivares then invited Dana Tomlin, PhD, professor (adjunct) at the School of the Environment, whom Friscia referred to as the “father of map algebra”; and Jill Roberta Kelly, PhD, geospatial lecturer in the School of Public Health, for expertise and collaboration.

“We met daily to discuss map-making, data availability, challenges (many!), and made sure the maps would convey a meaningful message for the public and decision makers,” said Olivares.

At the height of the pandemic, maps were being updated every five minutes. Despite challenges, particularly the immediacy and pressure of, as Olivares put it, “mapping a catastrophic pandemic while it is occurring,” the team’s work has had an ongoing impact on the way citizens, researchers, health care workers, and policymakers view the COVID-19 pandemic. For example, the nursing home case map helped the Yale New Haven Hospital system determine where staff members should deploy resources because nursing home case numbers had a major effect on who’s coming into the hospital.

While those numbers facilitate the hospital system’s easier functioning, it’s actually the removal of anomalous data that makes other maps useful and unique.

“If you take a map of Connecticut and eliminate cases in facilities where people can’t come and go, it paints a much more positive picture of what’s actually going on,” noted Friscia. “It would have been easy for us to go down a path where we make a bunch of assumptions and turn out these maps—but bringing in the experts really made a huge difference in what we were able to turn out.”

One of those experts is Dana Tomlin. “What Dana brought to the project was a different way to look at the data that I’d never really considered…all of a sudden it tells such a different story,” said Friscia. “[Dana] is also able to take data and project what other data could look like from it.”

Creating COVID-19 Data Maps to Inform the Public, Clinicians, and Policymakers

One example is the U.S. COVID Presence Map, which takes a set of case numbers and cross-sections it with population densities from U.S. Census data. Tomlin believes this map is “the one most likely to affect on-the-ground behavior. As simple as it is (and perhaps because of that simplicity), this map responds directly and quite literally to the question that each of its viewers inevitably raises: What’s happening in my own backyard?”

In addition to presence maps and case number maps of specific locations and populations, users can also find maps on racial and ethnic disparities in COVID-19 mortality in the United States, the risk of complications related to COVID-19 infection, and travel time to COVID-19 testing sites. The mapping project is useful not only for understanding and responding to the current pandemic, but also in informing responses to future pandemics.

“These maps offer a way to visualize correlation between seemingly unrelated things,” said Fansler. Those correlations can help us understand the spread of a disease, as well as its impact on society, the economy, and communities. “Trying to approach this from different angles gives people different perceptions about how a virus in the future might spread. Maybe by thinking about COVID in this way, when the next [pandemic] comes around, we’ll be a little bit quicker to look at those variables that we didn’t think about at the beginning of COVID, and hopefully policymakers will have more tools at their disposal to stem the spread of the next virus.”

The mapping project also shows the utility of geospatial information technology in understanding and responding to pandemics. Said Tomlin, “We live in a world where our ability to sense, to interpret, and to affect that world has come to involve digital tools and techniques that can be just as engaging as the topics to which they are applied.”

It takes a village to effectively respond to a pandemic—something that Yale has proved quite capable of during COVID-19. As Dean Brown said, “[The COVID-19 Mapping Initiative] lays the groundwork for future collaborations.”

Originally published 2021 (issue 166): updated May 16, 2022.