Table 1.

Seroprevalence of varicella in AS for Elementary and College Students, 2011, by selected variables

Variable	Elementary School Students			College Students
	No. students	Seroprevalence, % (95 CI)	P-Value	No. students	Seroprevalence, % (95 CI)	P-Value
Sexa			0.454			1.000
Female	258	77.5 (72.4–82.6)		127	96.1 (92.7–99.5)
Male	248	81.9 (77.1–86.7)		73	97.3 (93.5–100.0)
Ageb			0.388			1.000
4–6 yrs	304	76.0 (73.3–82.6)		NA	NA
7–9 yrs	205	79.5 (75.6–86.4)		NA	NA
17–19 yrs	NA	NA		80	97.5 (94.1–100.0)
20–22 yrs	NA	NA		83	96.4 (92.4–100.0)
≥23 yrs	NA	NA		43	97.7 (93.2–100.0)
Regionc			0.093			0.672
Central	91	73.6 (63.4–82.3)		58	96.6 (88.1–99.6)
East	68	83.8 (72.9–91.6)		26	96.2 (80.4–100.0)
Midwest	249	80.3 (74.8–85.1)		86	95.4 (88.5–98.7)
West	105	70.5 (60.8–79.0)		37	100.00 (90.5–100.0)
Place of birthd			0.277
AS	463	77.5 (73.5–81.3)		NA	NA
Outside ASe	21	90.5 (69.6–98.8)		NA	NA
History of varicella disease			<.001			1.000
No	247	63.6 (57.2–69.6)		66	97.0 (89.5–100.0)
Yes	211	93.4 (89.1–96.3)		127	97.6 (93.3–100.0)
Documented history of 1-dose of varicella vaccine			0.141			1.000
Yes	18	94.4 (72.7–100.0)		1	100.0 (2.5–100.0)
No	467	77.5 (73.5–81.2)		149	98.0 (94.2–100.0)

Note: CI=Confidence interval; AS= American Samoa

^aExcludes 16 students with missing information on gender.

^bExcludes 8 students with missing information on birth date or date of serum collection.

^cExcludes 1 student with missing information on region.

^dPlace of birth was only availablefor 484 elementary school students.

^e18 students were born in the United States, 1 student was born in Marshall Islands, 1 student was born in Australia, and 1 student in Tonga.