. Author manuscript; available in PMC: 2015 Dec 9.

Published in final edited form as: Pediatr Infect Dis J. 2014 Nov;33(11):1164–1168. doi: 10.1097/INF.0000000000000444

TABLE 3.

One-Dose and Two-Dose Varicella Vaccine Effectiveness Against All Varicella by Time Since Vaccination in Public School Students of West Virginia, 2010–2011

	Cases, n (%)	Controls, n (%)	VE (95% CI)	P Value	P Value
Unvaccinated	57 (50.4)	36 (16.6)	Reference
Years since receipt of first dose of varicella vaccine	N = 56	N = 181
<5 years	4 (3.5)	31 (14.3)	93.0 (75.0–98.1)	<0.001	Reference
5–9 years	31 (27.4)	93 (42.9)	88.0 (72.4–94.8)	<0.001	0.36
≥10 years	21 (18.6)	57 (26.3)	81.8 (57.8–92.1)	<0.001	0.15
Years since receipt of second dose of varicella vaccine	N = 20	N = 148
<3 years	7 (9.7)	65 (90.3)	92.8 (72.4–98.1)	<0.001	Reference
3–5 years	11 (12.5)	77 (87.5)	87.8 (65.1–95.8)	<0.001	0.240
>5 years	2 (25.0)	6 (75.0)	50.7 (0–97.5)	0.64	<0.001

VE indicates vaccine effectiveness; 95% CI, 95% confidence interval.