Table 1.
Colony forming units of S. aureus shed per adult
| Group I | Group II | Average | |||||
|---|---|---|---|---|---|---|---|
| Cycle | (BP) | (CHR) | (BP) | (CHR) | (BP) | (CHR) | (CHR) |
| 1 | 1.3 × 106 | 8.1 × 105 | *1.4 × 105 | BDL | 7.1 × 105 | 4.1 × 105 | 6.1 × 106 |
| 2 | 8.3 × 105 | 8.1 × 105 | 4.6 × 104 | BDL | 4.4 × 105 | 4.1 × 105 | 3.9 × 106 |
| 3 | 9.1 × 105 | 4.2 × 105 | *1.0 × 106 | *4.3 × 105 | 9.6 × 105 | 4.3 × 105 | 1.3 × 106 |
| 4 | 3.6 × 105 | 8.1 × 104 | *4.3 × 105 | *4.5 × 105 | 3.9 × 105 | 2.6 × 105 | 6.8 × 105 |
| Average | 8.4 × 105 | 5.3 × 105 | 4.1 × 105 | 2.2 × 105 | 6.3 × 105 | 3.8 × 105 | 3.0 × 106 |
| Standard Deviation | 3.8 × 105 | 3.5 × 105 | 4.4 × 105 | 2.5 × 105 | 2.7 × 105 | 7.6 × 104 | 2.5 × 106 |
*Water samples where MRSA was detected.
Based on analysis of water samples from a large pool with 10 adults using two different selective media, Baird Parker (BP) and Chromagar (CHR); numbers shown correspond to confirmed numbers of S. aureus based upon detection of the specific gyrA gene. BDL = below detection limit. BDLs were transformed to 1/2 of BDLs in order to estimate averages and standard deviations. The theoretical detection limit (2.8 × 103 CFU/person) can be calculated from the volume of the large pool (1400 L), the largest membrane filtration volume (50 ml) and noting that 10 people bathed per cycle (adapted Elmir et al. [17]).