In Chicago, a recent report found that 70 percent of people who died from COVID-19, the disease caused by the coronavirus, are black — even though the city's population is just 30 percent black.

In Milwaukee County, which is 27 percent black, the figure is 81 percent.

And public health officials tracking the coronavirus have seen similar disproportionate impacts on African Americans in Philadelphia, Detroit and other cities.

But just how widespread the disparities might be across the country is difficult to know, because most states and the federal government haven't released demographic data on the race or ethnicity of people who've tested positive for the virus. That's created an information gap that could aggravate existing health disparities, prevent cities and states from equitably distributing medical resources and potentially violate the law, advocates say.

"Civil rights laws prohibit federally funded health care providers from administering services in a discriminatory manner," said Kristen Clarke, president and executive director of the Lawyers' Committee for Civil Rights Under Law, which joined with medical professionals Monday to call for the immediate release of racial and ethnic data on coronavirus infections, testing and deaths. "Our ability to fully understand and confront this pandemic requires and demands that we obtain racial data now.”

Some Democratic lawmakers have also pressed the federal government to release the data. Advocates say the lack of information makes it impossible to know whether resources are being fairly distributed or whether some groups are getting cut out, notably those, like African Americans, who are more likely to have underlying health conditions.

On Tuesday, President Donald Trump called the impact of the coronavirus on African Americans a "real problem" that was showing up "strongly" in the data. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, added that pre-existing conditions that are more prevalent among African Americans, including asthma and diabetes, are a factor. “We’re very concerned about that,” he said.

Low-income people of color are also more likely to have jobs that can't be done remotely, meaning they're more likely to be exposed to the virus while more affluent professionals are able to stay at home. And they're less likely to have access to high-quality private testing or medical care.

"I'm concerned this will be yet another case where there's a huge difference between people who are more wealthy and people who are poor, and there's going to be a difference between people of color and how much they suffer," Dr. Marcus Plescia, the chief medical officer for the Association of State and Territorial Health Officials, said. “We have a longstanding legacy of bias and racism in our country and we’re not going to get beyond that quickly.”

Data difficulties

The Centers for Disease Control and Prevention has included age and gender in the flood of data that it has released daily since the pandemic began. The agency hasn't released racial or ethnic data and didn't respond to a request for comment. On Tuesday, Seema Verma, administrator of the Centers for Medicare & Medicaid Services, said the federal government would release data soon.

Most states and territories haven't released racial or ethnic data, either. Plescia said he knows of only nine: Connecticut, Illinois, Louisiana, Michigan, Minnesota, North Carolina, South Carolina, Virginia and Washington, D.C.

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The rest either have struggled to gather the information or have raised concerns about the reliability of data collected under less-than-ideal circumstances, such as at drive-up testing centers or in hastily built medical tents.

Race "is an area of data that we have challenges with to begin with," Plescia said, adding that, even during normal times, some doctors or clinics might guess a patient's race or make assumptions when gathering information, sometimes forcing public health officials to track the data down later. The current crisis, with health care providers overwhelmed, makes data collection even more difficult, he said.

Some states say as many as 40 percent of lab reports are coming in with incomplete information, compared to about 10 percent under normal circumstances, said Janet Hamilton, executive director of the Council of State and Territorial Epidemiologists, an organization of infectious disease specialists working for health departments.

Many states don't have the technology to quickly gather and distribute patient demographic data, and medical providers might, for example, leave race out of the paperwork they send to labs that run the coronavirus tests, Hamilton said. "We have an outbreak moving with speed and intensity, and we haven't been funded with the right infrastructure to support that need."

Also, in some cases, especially in states that haven't yet seen high numbers of infections, health authorities have withheld racial data deliberately to avoid stigmatizing certain racial or ethnic groups or to avoid the appearance that certain groups are immune, Hamilton said.

"It's really important to underscore that this virus is a rapidly moving infectious virus and that it's crucial that everyone understands that they are at risk," she said. "This isn't a virus that is only impacting certain groups or subgroups."

‘Not only the message but the messenger'

But health equity experts say state and federal agencies need to do a better job of documenting and addressing potential racial disparities.

"I'm glad that we're all in this together," said Stephen B. Thomas, who directs the Center for Health Equity at the University of Maryland in College Park. "But when we're all in this together, the dominant culture doesn't see a reason to talk about different racial and ethnic groups. It's just not even on the radar screen."

The underlying conditions that are often listed as risk factors for coronavirus complications include heart disease, diabetes and asthma. Those are the "very diseases that black folks and brown folks have been dying from, even before COVID-19," Thomas said, "and so to see the data come out with absolutely no reference to racial or ethnic breakdowns has given me pause."

Data is crucial to ensure that public health interventions are working for everyone, he said. "If we find that black folks aren't even being tested, if we find Latino folks are afraid to go to test sites because of fear of ICE," Thomas said, referring to U.S. Immigration and Customs Enforcement, "then we have people walking around infected and they don't know it."

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If data shows that certain groups are being hit hard by the virus, it could pressure public officials and health authorities to do deliberate outreach to those communities, possibly working through churches or leaders who already have residents' trust.

Research shows that African Americans and Latinos are less likely to trust their doctors. That's in part because of racist policies and programs of the past, Thomas said, citing the infamous Tuskegee study that began in the 1930s, which left hundreds of African American men with untreated syphilis for decades.

Thomas added that most of the experts he's seen talking about the coronavirus on TV news haven't reflected the nation's racial diversity.

"It's not only the message but the messenger" that's important, he said. "And for certain groups, in particular African Americans and other groups that have historically been discriminated against simply because of who they are, we need to tailor the message to them."

In Michigan, where African Americans comprise 14 percent of residents but 41 percent of people who have died from the coronavirus, public relations consultant Greg Bowens last week issued a 12-point plan for outreach. The proposal, which he published on a local news site, includes asking cellphone companies to blast out text messages, flooding urban radio with targeted advertising and leaning on black professionals to push clear messages to say: "Yo the Rona is real. Stay home!"

It's crucial to combat some of the rumors that circulated during the early days of the outbreak, when the coronavirus seemed mainly to be infecting people in China or wealthy business travelers. Bowens, who is also the founder and past president of the NAACP chapter in the Detroit suburbs of Grosse Pointe and Harper Woods, even heard a rumor, based on the fact that there weren't many known infections in Africa, that people with dark skin were immune, he said. He worries that people initially didn't take the virus seriously enough, contributing to the deep toll that he's seen the virus take on Detroit and surrounding communities. He said he knows seven people who have died from the virus.

"We're very good at coming up with advertising and messaging that has a little pop to it, a little snazz to it, in order to sell tennis shoes," he said, noting that advertisers know how to target specific groups to sell their products. "There's no reason why we can't apply that kind of methodology to marketing messages around this virus in order to get people's attention."

Releasing racial and ethnic data needs to be an important priority for public health officials, said Dr. Georges Benjamin, the executive director of the American Public Health Association. Data can help states and the federal government decide where to focus their attention.

"If we're serious about making sure that we improve the health of our populations," he said, "then we will focus like a laser on those populations that we know historically are more at risk."