The ABC data team and FiveThirtyEight's review of thousands of test sites across the country uncovered that where people live and how much money they make influences how easy it is for them to get tested.
Some of the largest disparities were found in San Antonio, Texas, where testing sites near predominantly Black neighborhoods were 128% busier than those in predominately white neighborhoods.
Similarly, sites near predominately Latinx communities in Philidelphia had 27% more demand than white communities.
However, he analysis found less disparities in access to testing in North Carolina.
In Raleigh, sites near Latinx communities showed no difference in demand, but the analysis found a 12% disparity between Black and white neighborhoods.
The analysis determined the potential demand for each testing site based on Census data, indicating the population of people in the immediately surrounding neighborhoods, assuming people would obtain COVID-19 tests at facilities nearest their homes. It also accounted for the demographics of those neighborhoods to understand what groups would be more likely to experience busier test centers. The findings are estimates and predictions. The analysis does not consider every factor that could impact testing capacity, including differences in site staffing or eligibility requirements to obtain a test.
Dr. Jose Cabanas, Wake County's medical director, said the county has worked to identified gaps in testing for months.
"Pretty early we started seeing a trend, a concerning trend about the disparities with regard to race and ethnicity in the community," Cabanas said. "Once we knew that, we became very intentional about how do we address that real time as the pandemic is evolving."
Currently, Hispanic residents account for 43% of the county's COVID-19 cases but only 10% of the population. Meanwhile, white individuals make up 68% of the county but account for only 36% of COVID-19 cases.
However, Cabanas said the county and state were strategic in where they placed testing sites, focusing on minority and historically marginalized neighborhoods.
North Carolina state health officials said they are constantly looking at Census-related data to predict what areas of the state might have vulnerable populations.
"We looked at demographic information on race, ethnicity. We looked at income, various health disparities, and particular those health disparities cardiovascular disease, diabetes that can lead to a poor outcome for COVID," explained Ben Money, NCDHHS deputy secretary for health services.
Since the ABC analysis, North Carolina officials enacted a plan to further expand testing for historically marginalized populations.
The state identified more than 100 priority ZIP codes and has started rolling out free, mass testing events throughout July to help combat the barriers of cost and transportation.
WATCH: This is what it's like to get a COVID-19 test
"Historically marginalized populations have always been disproportionately impacted by many diseases, so ensuring that this is in the forefront of our strategy and making sure they have the resources that they need," said Dr. Cardra Burns, NCDHHS senior deputy director.
However, officials recognize that increasing test sites doesn't necessarily mean those who need to be tested will come.
"Everyone still wrestles with, the fact that you are just building the access points to get to the testing and to make it as easy as possible for the community, doesn't mean that everybody is going to come right away, so you also have to build your communication plan and your sort of strategy to connecting the community to message that," Cabanas said.
Wake County is working with community organizations to help build trust with residents and get information to people in a language they understand.
Beyond getting people out to get COVID-19 testing, health officials are also hoping the work they do now to reach marginalized communities can extend after the virus is gone.
The continual disparities in healthcare is something Pete Tannenbaum, executive director of Alliance Medical Ministry, knows all too well. His nonprofit provides primary care to uninsured residents in Wake County.
"Pre-COVID, about 70% of our patients either did not receive healthcare at all or went to the emergency room for primary health care which is just taxing on the system. It's very, very expensive to do and the hospitals can't keep up with that," he explained.
The clinic is also located in one of the top ZIP codes for COVID-19 cases in the state--27610--and is identified as one of the priority areas for the state.
While the clinic doesn't do testing, Tannenbaum said it does monitor some COVID-19 patients after they recover. Currently, the clinic has more than 500 people waiting to get served.
State health officials want to use the infrastructure set up for COVID-19 testing to connect people to a primary care location like Alliance Medical Ministry.
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"Healthcare access and COVID testing aren't necessarily the same thing, and I think that's why we've been very intentional, particularly with the contractual arrangements with the testing vendors to make sure they are connecting people who don't have a medical home to health care," Money said.
You can find a COVID-19 testing site near you here.
To learn about the next mass testing event in Wake County, go here.
Contributing: The nationwide data analysis and additional reporting for this story was contributed by a team, including Soo Rin Kim and Matthew Vann of ABC News, Laura Bronner of FiveThirtyEight and Grace Manthey of ABC Owned Television Stations. The full analysis is here and an explanation of how we did it can be found here.