TABLE 2.
Comparison of transmission rates of MRSA and 3MDR-GN E. coli during the two study intervals
| Study interval | Pathogen (no. of isolates/total no. of patient cases/no. of cases at risk wards) | No. of genotypic clusters (maximal distance for cluster recognition) | Epidemiological assessment of genotypic clusters | Total no. of cases involved in probable transmissions (%) | No. of cases in risk wards with changed infection control procedures for 3MDR-GN (%) during interval II |
|---|---|---|---|---|---|
| I | MRSA (412/397/68) | 32 (≤6 alleles) | 8 clusters with probable transmissions, 16 clusters with unlikely transmissions, isolation 8 times from same patient but different colony morphology/phenotype results | 23 (5.8) | 15 (22.1) |
| E. coli (102/86/51) | 13 (≤10 alleles) | 1 cluster with probable transmission, 1 cluster with unlikely transmissions, isolation 11 times from same patient but different cases/colony morphology/phenotype results | 2 (2.3) | 2 (3.9) | |
| II | MRSA (325/325/57) | 15 (≤6 alleles) | 6 clusters with probable transmissions, 9 clusters with unlikely transmissions | 14 (4.3) | 6 (10.5)a |
| E. coli (120/120/45) | 8 (≤10 alleles) | 1 cluster with probable transmissions, 7 clusters with unlikely transmissions | 6 (5.0) | 0 (0)a |
a
Results of comparisons of transmission rates between interval I and II were not statistically significant for MRSA (P = 0.0980) or MDR E. coli (P = 0.4967).