Table 1.

Proportions of nosocomial infection by age and genotype^a

Group	Genotype	Age	Proportion of nosocomial infection	No. of patients
1	II.7	0–5	0.286	7
2	II.7	Rest	0.000	6
3	II.4	0–5	0.478	23
4	II.4	Rest	0.553	47
5	II.3	0–5	0.737	38
6	II.3	Rest	0.143	7
7	Unknown	0–5	0.688	48
8	Unknown	Rest	0.694	36
9	Rest	0–5	0.500	6
10	Rest	Rest	0.000	2
A	All genotypes	0–5	0.631	122
B	All genotypes	Rest	0.531	98
C	II.7	All ages	0.154	13
D	II.4	All ages	0.529	70
E	II.3	All ages	0.644	45
F	Unknown	All ages	0.690	84
G	Rest	All ages	0.375	8

^aGroups are defined as any combination of age group and genotype. Patients who tested positive for NoV after 2 to 4 days of admission were classified as indeterminate and were omitted from the analysis (n = 44).