Washington State University researchers have mapped which parts of the state may be most vulnerable to COVID-19 – down to individual census tracts – using mortality data for chronic conditions such as heart disease, lung disease and diabetes.

People with those underlying illnesses are more likely to die from COVID-19. The “vulnerability index” from WSU’s Community Health and Spatial Epidemiology, or CHASE, Lab also accounts for age and population density, and uses those combined risk factors to rank neighborhoods’ susceptibility on a scale of 1 to 100.

The map does not predict who, or how many people, will get infected or die from the new coronavirus. Rather, it’s intended to assist policymakers and public health officials tasked with allocating limited resources, such as test kits, said Pablo Monsivais, a CHASE Lab epidemiologist who led the analysis.

Monsivais describes COVID-19 as one epidemic colliding with another.

“Despite how rich we are as a country and all the resources we have, and the most advanced health care system, we’re actually pretty sick,” Monsivais said. “Even before the pandemic, we were pretty sick, with heart disease being the number one killer in this country and in most high-income countries.”

Americans’ lifestyles are to blame, he said.

“It’s the fact that we don’t move enough. We overeat the wrong kinds of foods. We’re stressed. We smoke. And those are all contributing to the burden of cardiovascular disease,” he said. “And so, the fact that we already are sick going into this pandemic means that we’re at the tipping point, basically, of this infection leading to much more severe health impacts and death.”

Monsivais noted that cardiovascular diseases are especially prevalent in poor communities and communities of color. Those disparities, he said, are not the result of genetic factors but socioeconomic ones, such as access to health care.

“The disease conditions that we face are not equally distributed. That’s been like that as long as we’ve been measuring it,” he said. “We’ve had health inequities, but what’s happening now is that those health inequities are being amplified by COVID-19.”

The COVID-19 vulnerability index relies on five years’ worth of mortality information from the state Department of Health – about half a million data points, Monsivais said. The analysis builds on one of his previous studies, which found that people of color in Washington are far more likely than white residents to die before age 65.

Already, scientists have observed racial disparities among COVID-19 patients.

According to a study released Wednesday by the Centers for Disease Control and Prevention, about 90% of the 1,482 people hospitalized with the disease in March had underlying medical conditions.

Among the 580 hospitalized patients whose races were documented, about 33% were Black, although Black people make up less than 13% of the U.S. population.

The study also found that older people and men infected by the virus were more likely to experience severe symptoms.

Officials in Louisiana and the city of Chicago both have reported that Black patients have accounted for more than 70% of COVID-19 deaths, even though Black people make up closer to 30% of their populations.

Monsivais noted that COVID-19 presents a unique threat to the South, where young people are more likely to have underlying cardiovascular conditions.

Monsivais plans to apply for research funding that would help validate the results of the Washington vulnerability index. He said he needs access to COVID-19 data broken down by census tract. Currently, that data is broken down at the county level.