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. 2024 Jan;31(1):1-6.
doi: 10.1016/j.acra.2023.05.008. Epub 2023 May 11.

Prevalence of Pneumonia Among Patients Who Died with COVID-19 Infection in Ancestral Versus Omicron Variant Eras

Mark M Hammer  1 , Aaron D Sodickson  2 , Andrew D Marshall  3 , Jeremy S Faust  3
Affiliations

Prevalence of Pneumonia Among Patients Who Died with COVID-19 Infection in Ancestral Versus Omicron Variant Eras

Mark M Hammer et al. Acad Radiol. 2024 Jan.

Abstract

Rationale and objectives: The Omicron variant of COVID-19 is less severe than the ancestral strain, leading to the potential for deaths in patients infected with the virus but who die of other causes. This study evaluated the difference in rates of pneumonia among patients who died with SARS-CoV-2 infection in the ancestral vs Omicron eras.

Materials and methods: We identified patients who died within 30days of a positive SARS-CoV-2 test, from March 2020 through December 2022; variants were assigned based on the prevalent variant in the US at that time. We also obtained a control group from patients who died within 30days of a negative SARS-CoV-2 test in January 2022. The first CT after the test was reviewed in a blinded fashion and assigned a category from the RSNA Consensus Reporting Guidelines. The primary outcome was the difference in rates of positive (typical or indeterminate) COVID-19 findings in the ancestral vs Omicron eras.

Results: A total of 598 patients died during the ancestral era and 400 during the Omicron era, and 347 decedents comprised the control group. The rate of positive COVID-19 findings was 67/81 (83%) in the ancestral era and 43/81 (53%) in the Omicron era (P < .001), an absolute difference of 30% (95% CI 16%-43%). The rate of positive findings in the control group was 23/76 (30%).

Conclusion: During the Omicron era, 30% fewer SARS-CoV-2-associated deaths were associated with COVID-19 pneumonia and were caused either by nonpulmonary effects of the infection or were unrelated to the infection.

Keywords: COVID-19; COVID-19 pneumonia; Omicron.

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Conflict of interest statement

Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Mark Hammer reports a relationship with Radiological Society of North America that includes: board membership. Mark Hammer reports a relationship with National Cancer Institute that includes: funding grants.

Figures

Fig. 1
Figure 1
Deaths within 30 days of a positive COVID-19 test.
See this image and copyright information in PMC

References

    1. Hyams C., Challen R., Marlow R., et al. Severity of Omicron (B.1.1.529) and Delta (B.1.617.2) SARS-CoV-2 infection among hospitalised adults: a prospective cohort study in Bristol, United Kingdom. Lancet Reg Health Eur. 2023;25 doi: 10.1016/j.lanepe.2022.100556. - DOI - PMC - PubMed
    1. Lauring A.S., Tenforde M.W., Chappell J.D., et al. Clinical severity of, and effectiveness of mRNA vaccines against, covid-19 from omicron, delta, and alpha SARS-CoV-2 variants in the United States: prospective observational study. BMJ Br Med J. 2022;376 doi: 10.1136/bmj-2021-069761. - DOI - PMC - PubMed
    1. Strasser Z.H., Greifer N., Hadavand A., et al. Estimates of SARS-CoV-2 Omicron BA.2 subvariant severity in New England. JAMA Netw Open. 2022;5 doi: 10.1001/jamanetworkopen.2022.38354. - DOI - PMC - PubMed
    1. Bálint G., Vörös-Horváth B., Széchenyi A. Omicron: increased transmissibility and decreased pathogenicity. Signal Transduct Target Ther. 2022;7:1–3. doi: 10.1038/s41392-022-01009-8. - DOI - PMC - PubMed
    1. Talbot T.R., Hayden M.K., Yokoe D.S., et al. Asymptomatic screening for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) as an infection prevention measure in healthcare facilities: challenges and considerations. Infect Control Hosp Epidemiol. 2023;44:2–7. doi: 10.1017/ice.2022.295. - DOI - PubMed

Supplementary concepts