TABLE 1.

Number of ciprofloxacin-resistant Streptococcus pneumoniae isolates in PFGE groups and clusters

Parameter	Value for isolates collected during study period		P value
	1997 to 2002 (n = 82)	2003 to 2005 (n = 123)
No. of groups (3 or 4 isolates)	6	4
Total no. of isolates in groups	19	14	0.0324
No. of clusters (≥5 isolates)	3	7
Total no. of isolates in clusters	24	72	0.0001
No. of groups and clusters (≥3 isolates)	9	11
Total no. of isolates in groups and clusters	43	86	0.0125