Table 3. Risk of SARS-CoV-2 Omicron (BA.1 lineage) variant infection among people who received booster vaccination relative to booster-eligible people^a, according to time after receiving a booster vaccine dose.

			Adjustedb		Unadjusted
Vaccine status at testing	Case	Control	Odds ratioc	P value	Odds Ratioc	P value
Primary Series: 150+ days after second dose (pre-booster dose)	3,421	38,446	-	-	-	-
Boosted: 14–59 days after booster (third) dose	263	5,637	0.45 (0.39, 0.52)	<0.001	0.52 (0.46, 0.60)	<0.001
Boosted: 60–89 days after booster (third) dose	164	2,313	0.56 (0.47, 0.66)	<0.001	0.80 (0.68, 0.94)	0.006
Boosted: 90+ days after booster (third) dose	122	1,970	0.80 (0.66, 0.98)	0.030	0.70 (0.58, 0.84)	<0.001

^aLimited to people without prior documented SARS-CoV-2 infections; limited to booster-eligible people, booster-eligible defined as primary series recipients aged 12 years or more who completed their primary series (2 doses) 150+ days prior to the test and were yet to receive a booster (third) dose; 150 days was selected as it reflects the CDC booster recommendations at the time of manuscript submission.

^bAdjusted for date of test, age (in years), sex, race/ethnicity, insurance, comorbidity (Charlson Score), SVI (Social Vulnerability Index) of zip code, presence of a documented prior infection, municipality, and number of nonemergent visits during the year prior to vaccine rollout in Connecticut (December 2, 2019 and December 1, 2020).

^cPoint estimate (95% confidence interval).