Table 3.

Hospitalisation outcomes for patients with the delta variant compared with patients with the alpha variant, by vaccination status

	Alpha variant*	Delta variant*	Adjusted HR (95% CI)†, delta variant vs alpha variant	p value‡
Hospital admission
Unvaccinated or <21 days after first vaccination dose	536/28 029 (1·9%)	149/6681 (2·2%)	2·32 (1·29–4·16)	..
≥21 days after first vaccination dose with or without second vaccination dose	228/6627 (3·4%)	47/2001 (2·3%)	1·94 (0·47–8·05)	0·82
Hospital admission or emergency care attendance
Unvaccinated or <21 days after first vaccination dose	1095/28 029 (3·9%)	369/6681 (5·5%)	1·43 (1·04–1·97)	..
≥21 days after first vaccination dose with or without second vaccination dose	353/6627 (5·3%)	129/2001 (6·4%)	1·58 (0·69–3·61)	0·82

Data are n/N (%) except where otherwise stated. HR=hazard ratio.

^*These crude descriptive frequencies are unadjusted for age and other confounders, and so they are not directly comparable between the groups.

^†Stratification for age group, ethnicity, lower-tier local authority, calendar week, vaccination status; regression adjustment for age, sex, index of multiple deprivation, specimen date, and international travel status.

^‡p values are for tests for interaction between vaccination status and variant.