Natural disasters and epidemics compound the burden of disease experienced by certain communities. In the 1918 flu pandemic, Jim Crow policies meant blacks received inferior care, if they received any. The 1995 heat wave in Chicago killed more than 700 people, disproportionately in black and low-income neighborhoods.

And numerous empirical studies confirm gross differences in life expectancy by race and ethnicity, gaps that appear at the national and local levels. In Chicago, for example, there is a nine-year gap between the life expectancies for black and white residents, with more than 3,000 excess deaths (deaths that would not have occurred if the black mortality rate were equal to the white mortality rate) among black people there every year. Add Covid-19 to the mix and there’s an even richer recipe for devastation.

Black communities have experienced the consequences of structural inequities in wealth, housing and education, to name a few areas. Our scientific data, along with the stories from everyday people, is what sheds light on these realities.

When the time comes to rebuild our health systems, we must commit to finding ways to structure and standardize the collection of all types of demographic data, of information not only about race and ethnicity, but also gender identity, sexual orientation and preferred language that have made people more vulnerable to the blows of public health emergencies. When institutions register patients, they must also have these categories on intake forms. Not everyone collects this information, but it must become the normal way of doing business.

In 1899, W.E.B. Du Bois advised in his seminal study on the black community in Philadelphia that “we must study, we must investigate, we must attempt to solve; and the utmost that the world can demand is, not lack of human interest and moral conviction, but rather the heart-quality of fairness and an earnest desire for the truth despite its possible unpleasantness.”

Any effective plan to fight Covid-19 must be shaped by an understanding of its spread and impact among communities of color and others marginalized in society. If we ignore structural inequities, we will ultimately increase the burden of disease not just for those most marginalized but for everyone.

This article has been updated to reflect news developments.

Aletha Maybank (@DrAlethaMaybank) is the chief health equity officer at the American Medical Association.

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