In Covid-19 hotspot counties across the United States, Latino and Black people were hit particularly hard, according to new research published Friday by the US Centers for Disease Control and Prevention.

Researchers analyzed cumulative case totals from February through June. Among 79 hotspot counties that also had data on race, more than 96% had disparities in Covid-19 cases in one or more racial or ethnic minority group.

“These findings illustrate the disproportionate incidence of Covid-19 among communities of color, as has been shown by other studies, and suggest that a high percentage of cases in hotspot counties are among person of color,” the authors said.

Latino populations were the largest group who lived in hotspot counties and had disparities in cases in the population. These disparities were found in three-quarters of the hotspot counties, where about 3.5 million Hispanic people live.

Black people were the next largest group, with about 2 million people living in 22 hotspot counties, where there were disparities in cases identified.

This was followed by more than 60,000 American Indian/Alaska Natives living in three counties, nearly 36,000 Asian people in four counties and about 31,000 Native Hawaiian and other Pacific Islander persons in 19 hotspot counties, with disparities in cases within the population.

There are a number of factors that could lead to the increased risk for Covid-19 in these populations, including structural factors, such as economic and housing policies, social factors, such as essential worker employment status requiring in-person work, and long-standing discrimination and social inequities that can lead to increased risk of disease, such as limited access to health care and underlying medical conditions.

Disparities were identified as either a difference of 5% or more between the proportion of cases and the proportion of the population or as a ratio of 1.5 or greater for the proportion of cases to the proportion of the population.

The research does have some limitations, the authors said, such as the fact more than half of the hotspot counties did not report enough race data and had to be excluded from the analysis.