TABLE 1 .
Ciprofloxacin susceptibility profiles of the Los Angeles and Chicago USA300 household MRSA isolates and SNPs in their grlA and gyrA genes
| Household | Region | na | Ciprofloxacin susceptibilityb (MIC [μg/ml]) | grlA position 80 nucleotide | gyrA position 84 nucleotide |
|---|---|---|---|---|---|
| 8010 | Los Angeles | 7 | R (>4.0) | Y | L |
| 8012 | Los Angeles | 11 | R (>4.0) | Y | L |
| 8013 | Los Angeles | 3 | S (1.0) | S | S |
| 8035 | Los Angeles | 8 | S (1.0) | S | S |
| 8036 | Los Angeles | 3 | R (>4.0) | Y | L |
| 8056 | Los Angeles | 3 | R (>4.0) | Y | L |
| 8113 | Los Angeles | 8 | R (>4.0) | Y | L |
| 8174 | Los Angeles | 5 | R (>4.0) | Y | L |
| 8182 | Los Angeles | 6 | R (>4.0) | Y | L |
| 8203 | Los Angeles | 9 | R (>4.0) | Y | L |
| 8211 | Los Angeles | 7 | R (>4.0) | Y | L |
| 8217 | Los Angeles | 1 | NDc | Y | L |
| 9002 | Chicago | 12 | S (0.5) | S | S |
| 9011 | Chicago | 9 | R (>4.0) | Y | L |
| 9012 | Chicago | 5 | S (0.5) | S | S |
| 9032 | Chicago | 6 | S (0.5) | S | S |
| 9033d | Chicago | 13 | S (0.5) | S | S |
| 9101 | Chicago | 9 | R (>4.0) | Y | L |
| 9131 | Chicago | 5 | S (1.0) | S | S |
| 9141e | Chicago | 5 | R (>4.0) | Y | L |
| 9150 | Chicago | 11 | S (0.5) | S | S |
a
Number of isolates sequenced in the household.
b
R, resistant; S, susceptible.
c
ND, MIC not determined.
d
One isolate (120381) in household 9033 had grlA 80F and gyrA 84L SNPs and was ciprofloxacin sensitive.
e
One isolate (119813) in household 9141 did not have these SNPs.