Table 2.

Univariate and multivariate analysis for risk of hospitalization among BA.4 and BA.5 cases.

	Univariate analysis			Multivariable analysis
	RR	95% CI	p–value	aRR	95% CI	p–value
Sex
Males	ref			ref
Females	1.45	[0.43–4.93]	NS	1.30	[0.34–5.30]	NS
Age
Under 70	ref			ref
70 and over	12.96	[3.59–46.74]	<0.001	3.33	[0.84–14.60]	NS
Risk factors a
No	ref			ref
Yes	30.44	[3.83–242.16]	<0.001	16.72	[2.59–326.86]	<0.05
Vaccination status b
1 dose or less	ref
2 doses or more	0.47	[0.13–1.65]	NS	2.89	[0.61–11.08]	NS
Travel
No	ref
Yes	0.50	[0.11–2.33]	NS
Cluster
No	ref
Yes	2.50	[0.65–9.61]	NS

RR, risk ratio; CI, confidence interval; aRR, adjusted risk ratio; ref, reference category; NS, not significant.

^aRisk factors include hypertension, diabetes, heart disease, kidney disease, respiratory illness, immunosuppression, obesity, cancer, neuromuscular disease, and/or pregnancy.

^bA previous infection was considered as a dose.