Table 3.

Infection risk and vaccine effectiveness against confirmed or probable* Beta infection, by vaccination status,**in cohort of exposure events by contacts of non-institutionalized primary Beta cases, Israel, Dec 11, 2020 – Mar 25, 2021. (N=350)

	n/n (%)	VE (95% CI; p value)***
Infection
Unvaccinated	54/248 (22)	Ref
Initially-vaccinated	8/36 (22)	—-
Partially-vaccinated	7/33 (21)	3 (-115 – 63; p >0·99)
Fully-vaccinated	2/33 (6)	72 (-5 – 97; p = 0·04)
Total	71/350 (20)
Symptomatic infection
Unvaccinated	36/248 (14)	Ref
Initially-vaccinated	7/36 (19)	—-
Partially-vaccinated	5/33 (15)	-4 (-167 – 68; p >0·99)
Fully-vaccinated	0/33 (0)	100 (19 – 100; p = 0·01
Total	48/350 (14)
Hospitalization
Unvaccinated	10/248 (4)	Ref
Initially-vaccinated	0/36 (0)	—-
Partially-vaccinated	0/33 (0)	100 (-235 – 100; p = 0·61)
Fully-vaccinated	0/33 (0)	100 (-235 – 100; p = 0·61)
Total	10/350 (3)
Death
Unvaccinated	2/248 (0.8)	Ref
Initially-vaccinated	0/36 (0)	—-
Partially-vaccinated	0/33 (0)	100^
Fully-vaccinated	0/33 (0)	100^
Total	2/350 (0.6)

VE = vaccine effectiveness; CI = confidence interval; Ref = reference group for VE calculation.

*Probable Beta infection is a SARS-CoV-2 PCR positive contact of a non-institutionalized primary Beta case without whole genome sequencing results.

**Vaccination status: Unvaccinated = never received BNT162b2. Initially-vaccinated = received one dose of BNT162b2 <14 days after the first dose. Partially-vaccinated = received one dose of BNT162b2 ≥14 days after the first dose or two doses <7 days after the second dose. Fully-vaccinated = received two doses of BNT162b2 ≥7 days after the second dose.

***95% CIs were calculated using the Clopper Pearson method and p values were determined using Fisher's Exact Test.

^CIs and p value not given if total number of cases <10 for a given infection type.