| Klebs. | Negative | N | 21 | 50 | 71 | 0.00** |
| % | 67.7% | 100.0% | 87.7% | |||
| Positive | N | 10 | 0 | 10 | ||
| % | 32.3% | 0.0% | 12.3% | |||
| E coli. | Negative | N | 28 | 45 | 73 | 0.96 |
| % | 90.3% | 90.0% | 90.1% | |||
| Positive | N | 3 | 5 | 8 | ||
| % | 9.7% | 10.0% | 9.9% |