Table 1 Mean levels and standard errors (se) of TVC at 22° and 36°C (CFU/mL) from water samples, prevalence of samples with microbial levels above the threshold levels established by Italian law (21) (no samples exceeded the CDC 2003 threshold value).
Cup fillers | ||||||
|---|---|---|---|---|---|---|
22°C | 36°C | |||||
T0 | T1 | Statist. anal. | T0 | T1 | Statist. anal. | |
Logarithmic mean | 1.6 (se = 0.15) | 1.3 (se = 0.14) | t = 1.38 (p = 0.16) | 1.7 (se = 0.15) | 1.2 (se = 0.13) | t = 2.24 (p = 0.02) |
Geometric mean | 42.7 | 21.9 | 47.9 | 17.4 | ||
% positives (Italian law) | 41.2 (42/102) | 36.2 (37/102) | McN = 1.71 (p = 0.19) | 60.8 (62/102) | 47.0 (48/102) | McN = 10.32 (p = 0.001) |
Air-water syringes | ||||||
22°C | 36°C | |||||
T0 | T1 | Statist. anal. | T0 | T1 | Statist. anal. | |
Logarithmic mean | 1.8 (se = 0.15) | 1.4 (se = 0.14) | t = 2.11 (p = 0.03) | 1.7 (se = 0.13) | 1.2 (se = 0.13) | t = 2.55 (p = 0.01) |
Geometric mean | 64.6 | 23.4 | 49.0 | 16.6 | ||
% positives (Italian law) | 48.9 (47/96) | 31.6 (30/95) | McN = 13.14 (p = 0.0003) | 63.5 (61/96) | 46.3 (44/95)) | McN = 13.14 (p = 0.0002) |
Tap water | ||||||
22°C | 36°C | |||||
T0 | T0 | |||||
Logarithmic mean | 0.5 (se = 0.07) | 0.7 (se = 0.10) | ||||
Geometric mean | 3.0 | 5.4 | ||||
% positives (Italian law) | 4.4 (4/91) | 29.3 (27/91) | ||||