Delta vs. SGTF infection analysis (SGTF means Omicron)
From 31 March 2020 through 6 December2021, there were 1,734 hospitalisedpatientsfor whom variant information was available either by genomesequencing (non-variant, Alpha, Beta, Delta),or TaqPath PCR (SGTF, as a proxy for Omicronfrom 1 October through 6 December). Of these, 792 (46%) were infected with the Delta variantfrom 1 April2021 (week 13) to 9 November 2021 (week 45),and 212 (12%) with SGTFfrom 1October 2021(week 42)to6 December2021 (week 48) (Figure 2).Among hospitalised individuals, 90.8% (1,037/1,142) had accumulated in-hospital outcome by 21December 2021.After controlling for factors associated with severe disease, SGTF infections diagnosed between 1 October and 30 November 2021 compared to Delta infectionsdiagnosed between April and November 2021 had a lower odds of severe disease (aOR 0.3, 95% CI 0.2-0.5) (Table 3). In addition to geographical differences, other factors identified as associated with an increasedodds of severe disease included olderage[40-59 years(aOR2.2, 95%CI1.0-5.0)and ≥60 years(aOR3.8, 95%CI1.7-8.6),compared to 19-24 years]andhaving a co-morbid condition(aOR 2.8, 95% CI 2.0-4.0).Individuals aged13-18 years(aOR0.2, 95%CI0.0-0.8, compared to 19-24 years)and females (aOR0.7, 95%CI0.5-1.0)had a lower odds of severe disease
