Table 1 All and varicella-related hospitalisations in the Centro Hospitalario Pereira Rossell (CHPR), Uruguay, between 1997 and 2005

Age (years)	1997	1998	1999	2000	2001	2002	2003	2004	2005	% Reduction (p value*)
<1
Total (N)	3081	2904	2779	3238	3901	3676	3664	4073	4094	63% (p<0.001)
Varicella (n)	8	33	28	23	16	17	14	21	12
Proportion (%)	0.26	1.14	1.01	0.71	0.41	0.46	0.38	0.52	0.29
1–4
Total (N)	2760	2709	2761	3439	4940	4676	3980	4645	4448	94% (p<0.001)
Varicella (n)	28	48	44	10	9	11	7	3	4
Proportion (%)	1.01	1.77	1.59	0.29	0.18	0.24	0.18	0.06	0.09
5–9
Total (N)	1224	1308	1468	1933	2818	2935	2999	3477	3432	73% (p<0.001)
Varicella (n)	11	11	13	5	5	13	10	11	8
Proportion (%)	0.90	0.84	0.89	0.26	0.18	0.44	0.33	0.32	0.23
10–14
Total (N)	1014	1085	1267	2325	3513	3510	2580	3136	3144	62% (p = 0.044)
Varicella (n)	1	9	4	4	2	4	4	7	5
Proportion (%)	0.10	0.83	0.32	0.17	0.06	0.11	0.16	0.22	0.16
Unknown age†	51	14	43	212	434	475	0	313	147
Total
Total (N)	8130	8020	8318	11 147	15 606	15 272	13 223	15 644	15 265	81% (p<0.001)
Varicella (n)	48	101	89	42	32	45	35	42	28
Proportion (%)	0.59	1.26	1.07	0.38	0.21	0.29	0.26	0.27	0.18
Characteristics of cases
Male/female (n)	26/22	47/54	46/43	23/19	22/10	22/23	21/14	22/20	11/17
Without underlying condition	42	88	80	40	29	41	33	34	26
Immunosuppressed/malnourished‡	3	8	8	2	2	4	0	7	2
Other	0	0	0	0	1	0	1	1	0
Unknown	3	5	1	0	0	0	1

Other, celiac disease, nephritic syndrome or diabetes.
*Fisher exact test, % reduction from 1997 to 1999 until 2005.
†There were no varicella cases in individuals of unknown age.
‡Immunosuppression due to leukaemia, disease requiring corticosteroid therapy or HIV.
N, total number of hospitalisations; n, number of varicella-related hospitalisations.