Table 1.

Immunologic status of the varicella-zoster virus of healthcare workers according to birth year and age group.

	Total	Positive	Indeterminate	Negative
Birth year
1950–1954	1	1 (100)	0	0
1955–1959	4	4 (100)	0	0
1960–1964	15	15 (100)	0	0
1965–1969	29	28 (97)	1 (3)	0
1970–1974	20	18 (90)	2 (10)	0
1975–1979	28	26 (93)	2 (7)	0
1980–1984	140	135 (96)	1 (1)	4 (3)
1985–1989	350	329 (94)	10 (3)	11 (3)
1990–1994	908	816 (90)	49 (5)	43 (5)
1995–1999	575	512 (89)	34 (6)	29 (5)
Age
>60	4	4 (100)	0	0
55–59	15	15 (100)	0	0
50–54	29	28 (97)	1 (3)	0
45–49	17	16 (94)	1 (6)	0
40–44	17	16 (94)	1 (6)	0
35–39	113	108 (96)	3 (3)	2 (2)
30–34	309	291 (94)	8 (3)	10 (3)
25–29	867	780 (90)	47 (5)	40 (5)
20–24	699	626 (90)	38 (5)	35 (5)
Total	2070	1884 (91)	99 (5)	87 (4)

Data are no. (%) of healthcare workers, unless otherwise indicated.