Days after declaring racism a serious public health threat, the Centers for Disease Control and Prevention released a pair of studies further quantifying the disproportionate impact of COVID-19 on communities of color.

The studies, published Monday in Morbidity and Mortality Weekly Report, examine trends in racial and ethnic disparities in hospitalizations and emergency room visits associated with COVID-19 in 2020.

CDC Director Rochelle Walensky said at a regular White House COVID-19 Response Team briefing that the new literature underscores the need to prioritize health equity, including in the country's accelerating vaccine rollout.

"These disparities were not caused by the pandemic, but they were certainly exacerbated by [it]," Walensky said. "The COVID-19 pandemic and its disproportional impact on communities of color is just the most recent and glaring example of health inequities that threaten the health of our nation."

After assessing administrative discharge data from March to December 2020, the CDC found that the proportion of hospitalized patients with COVID-19 was highest for Hispanic and Latino patients in all four census regions of the U.S.

Racial and ethnic disparities were most pronounced between May and July, it said, and declined over the course of the pandemic as hospitalizations increased among non-Hispanic white people. But such disparities persisted across the country as of December, most notably among Hispanic patients in the West.

The findings build on earlier studies about racial and ethnic disparities in COVID-19 hospitalizations by showing how they shifted over time and between regions.

Researchers point to two driving factors for the disproportionate hospitalizations among these minority groups: a higher risk of exposure to the virus and a higher risk for severe disease. They said differences in exposure risk associated with occupational and housing conditions, as well as socioeconomic status, are likely behind the demographic patterns they observed.

"Identification of the specific social determinants of health (e.g., access to health care, occupation and job conditions, housing instability, and transportation challenges) that contribute to geographic and temporal differences in racial and ethnic disparities in COVID-19 infection and poor health outcomes is critical," they said, adding that a better understanding of these factors at the local level can help tailor strategies to prevent illness and allocate resources.

The second study examined COVID-19-related emergency department visits in 13 states between October and December, and found similar disparities between racial and ethnic groups.

During that period, Hispanic and American Indian or Alaska Native people were 1.7 times more likely to seek care than white people, and Black individuals 1.4 times more likely.

Researchers noted that these racial and ethnic groups are also impacted by long-standing and systemic inequities that affect their health, such as limited access to quality health care and disproportionate representation in "essential" jobs with less flexibility to take leave or work remotely.

"Racism and discrimination shape these factors that influence health risks; racism, rather than a person's race or ethnicity, is a key driver of these health inequities," they explained.

Such inequities can increase the risk of exposure and delayed medical attention, further heightening the risks for severe disease outcomes and the need to seek emergency care.

Looking ahead, researchers said their findings could be used to prioritize vaccines and other resources for disproportionately affected communities in an effort to reduce the need for emergency care. Walensky also emphasized the implications of the new studies on and beyond the country's pandemic response.

"This information and the ongoing surveillance data we see daily from states across the country underscore the critical need and an important opportunity to address health equity as a core element in all of our public health efforts," she said.

A renewed push to address such inequity is now underway at the CDC, which late last week declared racism a "serious public health threat that directly affects the well-being of millions of Americans."

Walensky has directed the agency's departments to develop interventions and measure health outcomes in the next year. It's also provided $3 billion to support efforts to expand equity and access to vaccines, in addition to $2.25 billion previously allocated for COVID-19 testing in high-risk and underserved communities. The CDC has also launched a Racism and Health web portal to promote education and dialogue on the subject.

One area of particular focus is making sure the distribution of COVID-19 vaccines across the U.S. reaches the communities that have been hit hardest.

Data so far indicate that Black individuals make up roughly 12% of the country's population but just 8.4% of those who have received at least one dose, Walensky said. And while 18% of the country identifies as Hispanic or Latino, she said, they make up only 10.7% of those who have been vaccinated.

Officials at Monday's briefing highlighted further progress in the race to get shots into arms, noting that 120 million Americans have been vaccinated — 46% of adults have had at least one dose and 28% are fully vaccinated. And in exactly one week, all adults will be eligible to sign up for an appointment.

"This means that there has never been a better time than now for seniors and those eligible to get their shots," said Andy Slavitt, senior advisor on the White House COVID-19 Response Team. "Make an appointment today. And if you have someone in your life, particularly a senior, who has not gotten a shot yet, reach out and see what help they need."

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