Long-term immunogenicity after measles vaccine vs. wild infection: an Italian retrospective cohort study

Figures & data

Table 1. Characteristics of the two study groups at baseline

Variable	Disease group (n = 201)	Vaccine group (n = 410)	Total (n = 611)	p-value
Age (years) at enrollment; mean±SD (range)	22.9 ± 2.6 (18–35)	22.7 ± 2.5 (18–35)	22.8 ± 2.5 (18–35)	0.458
Female; n (%)	131 (65.2)	246 (60.0)	377 (61.7)	0.216
Allergy; n (%)	59 (29.4)	127 (31.0)	186 (30.4)	0.682
Chronic disease; n (%)	26 (12.9)	60 (14.6)	86 (14.1)	0.570

Figure 1. Proportion (%) of study participants in the vaccine and disease groups without circulating anti-measles IgG at study enrollment

p<0.0001.

Table 2. Multivariate logistic regression analysis of the determinants of seropositivity at enrollment

Variable	aOR	95%CI	p-value
Group (vaccine vs. disease)	0.25	0.13–0.47	<0.0001
Age at enrollment (years)	1.0	0.9–1.1	0.556
Male (yes/no)	1.3	0.8–2.1	0.299
Chronic disease (yes/no)	1.6	0.8–3.2	0.202

Chi2 = 59.5; p = 0.890

Figure 2. Kaplan-Meier PAS estimates for the vaccine and disease groups

p<0.0001.

Table 3. Multivariate cox semiparametric regression analysis of the risk predictors of PAS

Variable	aHR	95%CI	p-value
Group (vaccine vs. disease)	11.8	6.1–22.9	<0.0001
Age at enrollment (years)	0.87	0.80–0.95	0.002
Male (yes/no)	0.88	0.57–1.35	0.549
Chronic disease (yes/no)	0.71	0.37–1.38	0.310

Chi2 = 2.0; p = 0.160