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. 2023 Nov;95(11):e29204.
doi: 10.1002/jmv.29204.

Predictors of disease severity in SARS-CoV-2 omicron variant XBB sublineages and variants of interest

Jinghao Nicholas Ngiam  1 , Oon Tek Ng  2   3 , Matthias Paul Han Sim Toh  4   5 , Qi Gao  4 , Ai Jia Soong  4 , Joel Han Wen Teo  4 , Shannon Low  4 , Shawn Vasoo  2   3 , Jia Hui Li  6 , Koh Cheng Thoon  6 , Helen Oh  7 , Surinder Kaur M S Pada  8 , Say Tat Ooi  9 , Jade Soh  10 , Hei Man Wong  11 , Paul Anantharajah Tambyah  1   12   13
Affiliations

Predictors of disease severity in SARS-CoV-2 omicron variant XBB sublineages and variants of interest

Jinghao Nicholas Ngiam et al. J Med Virol. 2023 Nov.

Abstract

The Omicron variant has been reported to present with milder disease compared with Delta, although this may be due to immunity from vaccination and prior exposure. Predictors of severity with recent strains have not been well characterized. We retrospectively examined consecutive cases of moderate-to-severe COVID-19 (defined as requiring supplemental oxygenation, intensive care or mortality) admitted to seven tertiary hospitals across Singapore in April 2023. Whole genome sequencing was performed on each isolate to determine the sublineage, while baseline clinical, laboratory data and outcomes were tabulated. We reviewed 182 patients with moderate-to-severe illness and 466 controls hospitalized at the same time. Advanced age and presence of chronic kidney disease predicted adverse outcome. Previously reported markers such as radiographic evidence of pneumonia, elevated C-reactive protein and serum creatinine levels at presentation also correlated with adverse outcomes. There were no observable differences in outcomes with any specific Omicron XBB sublineage. We did not find any specific Omicron XBB sublineage that was associated with worse outcomes. Larger multinational studies would be important to track the clinical evolution of the virus in its current endemic state.

Keywords: COVID-19; Omicron sublineage; Singapore; whole genome sequencing.

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References

REFERENCES

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Supplementary concepts