Examining epidemiologic disparity across SARS-CoV-2 variant-dominant periods in Oklahoma County, Oklahoma (March 12, 2020-February 28, 2022).

Context: While it is well-known that age and race/ethnicity have been associated with poor COVID-19-related outcomes, it is less clear if vulnerable populations consistently experienced higher rates of poor outcomes over time.

Objective: Considering this, our study compared COVID-19-related outcomes by age group and racial/ethnic group across variant-dominant periods to assess how poor outcomes were experienced over time in Oklahoma County.

Design and methods: In this retrospective observational study, we used health department surveillance data to compare COVID-19-related average daily case, hospitalization, and case fatality rates across three time periods-each dominated by different SARS-CoV-2 variants in Oklahoma County, Oklahoma, US.

Results: When comparing across variant-dominant time periods, with respect to age, we observed that people age 65+ years consistently had the highest average daily rates of COVID-19-related hospitalization and death. With respect to race/ethnicity, we observed that American Indian/Alaska Natives consistently experienced the highest case rate, that Black people experienced high rates of hospitalization during the pre-Delta- and Delta-dominant time periods, and White people consistently experienced the highest rate of death. Hispanic people experienced the first surge of cases in the pandemic and subsequently had relatively low rates of COVID-19-related outcomes. Asian/Pacific Islanders had relatively low rates of COVID-19-related outcomes except a relatively high rate of death late in the Omicron-dominant period.

Conclusion: There is little evidence to suggest that once a segment of the population experiences high rates of COVID-19-related outcomes that they will benefit from lower rates of outcomes in subsequent variant-dominant time periods.