Findings from a new disease model may help public health officials evaluate and improve strategies for the next pandemic, researchers say.

Nearly two years ago, the US Centers for Disease Control and Prevention released its recommendations for a phased COVID-19 vaccine rollout. The agency prioritized groups based on occupation, age, living condition, and high-risk medical conditions in an effort to protect the vulnerable and reduce deaths.

But future pandemic responses should also consider ethnicity and social contact patterns that affect disease dynamics, says Claus Kadelka, assistant professor of mathematics at Iowa State University and lead author of a new paper in the Journal of Theoretical Biology.

“Many researchers in this field focus primarily on age. Who should get the vaccine first: older people who are the most vulnerable or younger people who have more contacts and can more easily spread the disease? Not considering other social dimensions when developing a vaccination strategy can lead to different or wrong predictions about the best way to prevent deaths,” says Kadelka.

The researchers point to multiple studies showing that COVID-19 has disproportionately affected people of color. The infection rate in predominantly Black counties in the US was three times higher than predominantly white counties in 2020, and the Navajo Nation had more cases per capita than any state in the country.

One reason for the disparity, the researchers say, is that people of color are more likely to work in public-facing and high-contact jobs (e.g., transportation services, grocery stores, meat packing facilities), which do not easily allow for physical distancing and remote work.

People of color are also more likely to live in higher-density or multi-generational housing where it’s harder to quarantine and prevent the spread of the virus.

Using data from the CDC, the US Census Bureau, and the US Bureau of Labor, the researchers applied a model they developed last year and incorporated different contact rates and occupational hazards by age and ethnicity. They then used the Iowa State supercomputer to analyze 2.9 million different vaccination strategies to identify those that achieved specific goals, such as minimizing infections or deaths from COVID-19.

“Our first big take-away from the study is that ‘ethnic homophily,’ the concept that people tend to interact more frequently with people from the same demographic group, matters,” says Kadelka. “The best strategy that included ethnicity prevented more deaths than the best strategy without ethnicity.”

Read the full article about public health strategies for the pandemic by Rachel Cramer at Futurity.