Table 1.
Descriptive statistics of stethoscopes, computer keyboards, and telephone handsets at H(0) and H(1): number and percentage of positive samples, overall CFUs counts and percentage reduction in CFUs from H(0) to H(1), means, standard deviations, medians, interquartile ranges (IQR), minima, and maxima.
| Object | Culture medium* | Time | Positive sample (%) | CFU total countb | % reduction | Meana (SD) | Mediana (IQR) | Mina | Max |
|---|---|---|---|---|---|---|---|---|---|
| Stethoscopes (n = 35) | TBC 36 | H(0) | 20 (57.1) | 3368 | −99.97 | 168.4 (304.7) | 19 (7.5 to 188) | 1 | 1110 |
| H(1) | 1 (2.9) | 1 | 1 (—) | 1 (1) | 1 | 1 | |||
| TBC 22 | H(0) | 22 (62.9) | 3678 | −100 | 167.2 (367) | 9.5 (5 to 55) | 1 | 1508 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| E. coli | H(0) | 5 (14.3) | 123 | −100 | 24.6 (30) | 11 (3 to 37) | 1 | 71 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Coliforms | H(0) | 15 (42.9) | 1009 | −100 | 67.2 (120) | 6 (3 to 62) | 1 | 361 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Enterococci | H(0) | 4 (11.4) | 14 | −100 | 3.5 (4.4) | 1.5 (1 to 6) | 1 | 10 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Staphylococci | H(0) | 21 (60) | 2605 | −100 | 124.1 (270) | 10 (5 to 70) | 2 | 1003 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| MRSA | H(0) | 10 (28.6) | 130 | −100 | 13 (16) | 5 (2 to 21) | 1 | 50 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Moulds | H(0) | 2 (5.7) | 2 | −50 | 1 (—) | 1 (1) | 1 | 1 | |
| H(1) | 1 (2.9) | 1 | 1 (—) | 1 (1) | 1 | 1 | |||
|
| |||||||||
| Telephone handsets (n = 37) | TBC 36 | H(0) | 33 (89.2) | 645 | −99.22 | 20 (30) | 11 (4 to 25) | 1 | 156 |
| H(1) | 3 (8.12) | 5 | 1.7 (0.6) | 2 (1 to 2) | 1 | 2 | |||
| TBC 22 | H(0) | 33 (89.2) | 580 | −98.79 | 18 (28.5) | 6 (2 to 22) | 1 | 152 | |
| H(1) | 4 (10.8) | 7 | 1.8 (1.5) | 1 (1 to 2.5) | 1 | 4 | |||
| E. coli | H(0) | 1 (2.7) | 1 | −100 | 1 (—) | 1 (1) | 1 | 1 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Coliforms | H(0) | 22 (59.5) | 194 | −99.48 | 8.8 (7.8) | 8 (2 to 12) | 1 | 30 | |
| H(1) | 1 (2.7) | 1 | 1 (—) | 1 (1) | 1 | 1 | |||
| Enterococci | H(0) | 2 (5.4) | 2 | −100 | 1 (—) | 1 (1) | 1 | 1 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Staphylococci | H(0) | 31 (83.8) | 427 | −99.53 | 13.8 (22.4) | 6 (2 to 14) | 1 | 99 | |
| H(1) | 2 (5.4) | 2 | 1 (—) | 1 (1) | 1 | 1 | |||
| MRSA | H(0) | 7 (18.9) | 23 | −100 | 3.3 (2.8) | 3 (1 to 4) | 1 | 9 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Moulds | H(0) | 6 (16.2) | 14 | −78.57 | 2.3 (2.4) | 1 (1 to 3) | 1 | 7 | |
| H(1) | 1 (2.7) | 3 | 3 (—) | 3 (3) | 3 | 3 | |||
|
| |||||||||
| Computer keyboards (n = 27) | TBC 36 | H(0) | 26 (96.3) | 512 | −99.41 | 19.7 (16.6) | 14 (8 to 33) | 1 | 66 |
| H(1) | 2 (7.4) | 3 | 1.5 (0.7) | 1.5 (1 to 2) | 1 | 2 | |||
| TBC 22 | H(0) | 25 (92.6) | 557 | −96.77 | 22.3 (15.2) | 21 (9 to 31) | 1 | 57 | |
| H(1) | 4 (14.8) | 18 | 4.5 (5.7) | 2 (1.5 to 7.5) | 1 | 13 | |||
| E. coli | H(0) | 11 (40.7) | 16 | −100 | 1.5 (0.7) | 1 (1 to 2) | 1 | 3 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Coliforms | H(0) | 21 (77.8) | 147 | −96.60 | 7 (6.5) | 5 (3 to 9) | 1 | 27 | |
| H(1) | 2 (7.4) | 5 | 2.5 (2.1) | 2.5 (1 to 4) | 1 | 4 | |||
| Enterococci | H(0) | 4 (14.8) | 4 | −100 | 1 (—) | 1 (1) | 1 | 1 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Staphylococci | H(0) | 25 (92.6) | 239 | −99.58 | 9.6 (9) | 5 (4 to 12) | 1 | 37 | |
| H(1) | 1 (3.7) | 1 | 1 (—) | 1 (1) | 1 | 1 | |||
| MRSA | H(0) | 6 (22.2) | 27 | −100 | 4.5 (3) | 4.5 (2 to 6) | 1 | 9 | |
| H(1) | 0 (0) | 0 | — (—) | — (—) | — | — | |||
| Moulds | H(0) | 20 (74.1) | 137 | −99.27 | 6.9 (8) | 3.5 (1.5 to 9) | 1 | 29 | |
| H(1) | 1 (3.7) | 1 | 1 (1) | 1 (1) | 1 | 1 | |||
*1 CFU of Acinetobacter was found only in one keyboard at H(0); TBC 36 and TBC 22, respectively, are total microbial load incubating at 36°C and 22°C; MRSA: methicillin-resistant Staphylococcus aureus; aonly positive samples; bsumming all CFUs per stethoscopes, computer keyboards, and telephone handsets.