Testing the Efficacy of the AltapureŽ System in the Cleaning of Hospital Equipment

Background: Routine decontamination of healthcare equipment remains challenging. Aerosolized peroxides have been proposed as an effective method. The Altapure ® system produces ultra small/sub-micron aerosolized droplets of peroxides for cleaning. 

Objective: To study the effectiveness of the Altapure® system in eliminating environmental contamination on hospital equipment. 

Methods: 13 hospital surfaces were inoculated with an estimated 9x10⁸ cfu/ml of Enterococcus faecium (ATCC 3577) in sterile saline or Mueller Hinton (MH) + 5% sheep’s blood and left to dry. Moistened cotton swabs were used to recover bacteria from ”control” surfaces prior to cleaning, and “test” surfaces after completion of the cleaning cycle. Swabs were streaked uniformly across blood agar (BA) plates and read after overnight incubation at 37ºC. Swabs for the sink cleaning trial were also streaked onto MacConkey plates.

Results: Enterococci suspended in sterile saline could not be recovered from any swabs. When suspended in MH+5% sheep’s blood, swabs consistently yielded too many colonies to count from control surfaces. Yields after test decontamination runs of different lengths are shown in the table. Decontamination was reduced on partially covered surfaces. Recovery of environmental bacteria from swabs of sink surfaces was decreased to zero on both BA and MacConkey plates for 2 of the 3 surfaces tested. Swabs from inside the sink drain showed decreased yet persistent growth.

Table 1: Percentages of tests with no Enterococci recovery for differing cleaning cycle lengths

Surface	Standard cycle length	Increased cycle length
	Tests with no bacterial recovery/Total tests completed (%)	Tests with no bacterial recovery/Total tests completed (%)
Blackberry keys	8/12 (66.67)	4/4 (100)
Blackberry screen	5/11 (45.45)	4/4 (100)
Blood pressure cuff	5/8 (62.5)	--
Blood pressure cuff Velcro	12/12 (100)	3/4 (75)
Chair fabric	2/2 (100)	4/4 (100)
Curtains	11/12 (91.67)	4/4 (100)
IV pole	10/10 (100)	--
Keyboard keys	6/12 (50)	3/4 (75)
Over-bed table	7/12 (58.33)	3/4 (75)
Phone keys	10/10 (100)	--
Pulse oximeter probe	5/8 (62.5)	3/4 (75)
Stethoscope tube	10/10 (100)	--
Electronic Thermometer Probe	6/12  (50)	--
Foam walker handle	9/12 (75)	3/4 (75)

*--  test results unavailable

Conclusions: Use of the Altapure® system reduced recovery of organisms in these experiments. Testing is needed to establish optimal cycle lengths and to assess field effectiveness of cleaning.