BioMed Research International

Research Article

Environmental Contaminants in Hospital Settings and Progress in Disinfecting Techniques

Table 1

Descriptive statistics of stethoscopes, computer keyboards, and telephone handsets at H and H: number and percentage of positive samples, overall CFUs counts and percentage reduction in CFUs from H to H, means, standard deviations, medians, interquartile ranges (IQR), minima, and maxima.


Object	Culture medium*	Time	Positive sample (%)	CFU total count^b	% reduction	Mean^a(SD)	Median^a (IQR)	Min^a	Max

Stethoscopes ()	TBC 36	H(0)	20 (57.1)	3368	−99.97	168.4 (304.7)	19 (7.5 to 188)	1	1110
	TBC 36	H(1)	1 (2.9)	1	−99.97	1 (—)	1 (1)	1	1
	TBC 22	H(0)	22 (62.9)	3678	−100	167.2 (367)	9.5 (5 to 55)	1	1508
	TBC 22	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	E. coli	H(0)	5 (14.3)	123	−100	24.6 (30)	11 (3 to 37)	1	71
	E. coli	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Coliforms	H(0)	15 (42.9)	1009	−100	67.2 (120)	6 (3 to 62)	1	361
	Coliforms	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Enterococci	H(0)	4 (11.4)	14	−100	3.5 (4.4)	1.5 (1 to 6)	1	10
	Enterococci	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Staphylococci	H(0)	21 (60)	2605	−100	124.1 (270)	10 (5 to 70)	2	1003
	Staphylococci	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	MRSA	H(0)	10 (28.6)	130	−100	13 (16)	5 (2 to 21)	1	50
	MRSA	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Moulds	H(0)	2 (5.7)	2	−50	1 (—)	1 (1)	1	1
	Moulds	H(1)	1 (2.9)	1	−50	1 (—)	1 (1)	1	1

Telephone handsets ()	TBC 36	H(0)	33 (89.2)	645	−99.22	20 (30)	11 (4 to 25)	1	156
	TBC 36	H(1)	3 (8.12)	5	−99.22	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
	TBC 22	H(1)	4 (10.8)	7	−98.79	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
	E. coli	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Coliforms	H(0)	22 (59.5)	194	−99.48	8.8 (7.8)	8 (2 to 12)	1	30
	Coliforms	H(1)	1 (2.7)	1	−99.48	1 (—)	1 (1)	1	1
	Enterococci	H(0)	2 (5.4)	2	−100	1 (—)	1 (1)	1	1
	Enterococci	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Staphylococci	H(0)	31 (83.8)	427	−99.53	13.8 (22.4)	6 (2 to 14)	1	99
	Staphylococci	H(1)	2 (5.4)	2	−99.53	1 (—)	1 (1)	1	1
	MRSA	H(0)	7 (18.9)	23	−100	3.3 (2.8)	3 (1 to 4)	1	9
	MRSA	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Moulds	H(0)	6 (16.2)	14	−78.57	2.3 (2.4)	1 (1 to 3)	1	7
	Moulds	H(1)	1 (2.7)	3	−78.57	3 (—)	3 (3)	3	3

Computer keyboards ()	TBC 36	H(0)	26 (96.3)	512	−99.41	19.7 (16.6)	14 (8 to 33)	1	66
	TBC 36	H(1)	2 (7.4)	3	−99.41	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
	TBC 22	H(1)	4 (14.8)	18	−96.77	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
	E. coli	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Coliforms	H(0)	21 (77.8)	147	−96.60	7 (6.5)	5 (3 to 9)	1	27
	Coliforms	H(1)	2 (7.4)	5	−96.60	2.5 (2.1)	2.5 (1 to 4)	1	4
	Enterococci	H(0)	4 (14.8)	4	−100	1 (—)	1 (1)	1	1
	Enterococci	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Staphylococci	H(0)	25 (92.6)	239	−99.58	9.6 (9)	5 (4 to 12)	1	37
	Staphylococci	H(1)	1 (3.7)	1	−99.58	1 (—)	1 (1)	1	1
	MRSA	H(0)	6 (22.2)	27	−100	4.5 (3)	4.5 (2 to 6)	1	9
	MRSA	H(1)	0 (0)	0	−100	— (—)	— (—)	—	—
	Moulds	H(0)	20 (74.1)	137	−99.27	6.9 (8)	3.5 (1.5 to 9)	1	29
	Moulds	H(1)	1 (3.7)	1	−99.27	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.