Racial/Ethnic and Geo-clustering Differentials in SARS-CoV-2 (COVID-19) Cumulative Incidence, Mortality and Temporal Trend in Delaware State, USA

Purpose: COVID-19, a respiratory disease caused by SARS-CoV-2 indicates subpopulation differentials in cumulative incidence (CmI) and mortality. We aimed to assess the racial/ethnic and geo-clustering in COVID-19 CmI and mortality in Delaware. Method: A cross-sectional ecologic design was used to assess COVID-19 mortality in April, May and November 2020. The binomial and poison regression models were utilized for race/ethnic and geo-clustering risk prediction, respectively. Results: As per late April, CmI remains to be flattened in DE, with the confirmed SARS-CoV-2, n=4575 (47.5 per 10,000), Sussex county (SC), n=2,114 (111.4 per 10,000), Kent county, n=728 (41.8 per 10,000) and New Castle county, n=1,701 (28.7 per 10,000). CmI was highest for Non-Hispanic blacks (NHB), 27% (n=1250) but lowest among Asian/Pacific Islanders, n=61 (1%). The disproportionate burden of COVID-19 CmI was highest among Hispanics, 100.2 per 10,000. COVID-19 cases were more prevalent among NHB (30%) and Hispanics (19%). Mortality was higher among NHB, 1.70 per 10,000 compared to Non-Hispanic whites (NHW), 1.34 per 10,000. COVID-19 mortality differed by race, with NHB relative to NHW 27% more likely to die, risk ratio (RR)=1.27, 95%CI, 0.85-1.89. Geo-clustering indicated a significant 50% increased mortality risk in SC compared to DE, incidence rate ratio (IRR)=1.50, 95%CI, 1.11-2.03.During November, the case fatality rate (CFR) in DE was 27 per 10,000, while in the US, the CFR was 25 per 10,000. Conclusions: The Delaware COVID-19 CmI indicates disproportionate burden on NHB and Hispanics; case clustering disproportionate burden in SC; and the risk of dying was highest among NHB.