Table 2.
Differences in the prevalence of mupirocin resistance, chlorhexidine non-susceptibility, and Panton–Valentine leukocidin (PVL) in clinical isolates of MSSA and MRSA*, from community and hospital settings, and from non-invasive and invasive infections*
| Prevalence | PR | 95% CI | P value | ||||||
|---|---|---|---|---|---|---|---|---|---|
| MSSA | MRSA | ||||||||
| N | n | % | N | n | % | ||||
| Mupirocin resistance | 487 | 0 | 0·0 | 32 | 4 | 12·5 | 133·1 | (9·16-∞) | <0·001 |
| Chlorhexidine non-susceptibility | |||||||||
| Genotypic (qacA) | 487 | 9 | 1·8 | 32 | 0 | 0·0 | 0·78 | (0·00–9·45) | 0·483 |
| Phenotypic (MIC = 4 mg/l)† | 486 | 15 | 3·1 | 32 | 3 | 9·4 | 3·04 | (0·93–9·95) | 0·093 |
| qacA or MIC = 4 mg/l | 486 | 23 | 4·7 | 32 | 3 | 9·4 | 1·98 | (0·63–6·25) | 0·212 |
| PVL toxin positivity | 487 | 17 | 3·5 | 32 | 2 | 6·3 | 1·79 | (0·43–7·41) | 0·330 |
MIC, Minimum inhibitory concentration; PR, prevalence ratio; CI, confidence interval.
P value = Fisher's exact test p value; statistically significant prevalence ratios are presented in bold type.
*
Prevalence ratios and confidence intervals have been estimated for categories with zero cell counts using a Woolf–Haldane correction.
†
One isolate was not recovered from frozen storage.