TABLE 2.

Prevalence of qnr genes in Enterobacteriaceae isolates from the United States (1999-2004)

Yearqnr locusNo. of isolates with locus/total no. of isolates (%)
K. pneumoniaeEnterobacter spp.E. coli
1999A4/21 (19)6/45 (13)0/9
B2/21 (10)5/45 (11)0/9
S0/210/450/9
Any6/21 (29)11/45 (24)0/9
2000A4/33 (12)1/38 (3)0/8
B2/33 (6)7/38 (18)1/8 (13)
S0/330/380/8
Any6/33 (18)8/38 (21)1/8 (13)
2001A2/20 (10)7/39 (18)0/5
B1/20 (5)8/39 (21)0/5
S0/200/390/5
Any3/20 (15)15/39 (38)0/5
2004A5/32 (16)4/38 (11)1/25
B1/32 (3)12/38 (32)0/25
S0/320/380/25
Any6/32 (19)16/38 (42)1/25 (4)
Total21 (20)50 (31)2 (4)