Table 2

Studies reporting interventions that led to a significant reduction in contamination of computer peripheral devices

StudyOutcome measuresMethod used to decontaminateBaseline contaminationPostintervention contamination
Albrecht et al 16 2013Total bacterial loadIsopropanol wipes using the six-step disinfection process guided by deBac-App. Control cleaned with new, dry ‘soft, lint-free cloth’1842 total CFU found on iPads in the clinical setting (162 median CFU)Clinical setting: 98.1% reduction (p=0.001)
Non-clinical setting: 99.4% reduction (p=0.001)
Control reduction rate: 51.1% (p value not reported)
Codish et al 24 2015Total bacterial loadMEDIWIPES (alcohol based) versus TriGene (quaternary ammonium based). Each device decontaminated 3×/dayInternal medicine: 92/92 (100%)
ICU: 62/70 (88.6%)
Total: 154/162 (95.1%)
Internal medicine: 76/92 (82.6%)
ICU: 31/70 (44.3%)
Total: 107/162 (66%)
P<0.001 for both internal medicine and ICU
Duszak et al 31 2014Total bacterial load‘Chlorascrub’ pads (chlorhexidine gluconate and isopropyl alcohol)Bacterial growth found on 100% of computer mice
Mean colony counts: 46.1±58.1
‘Demonstrable bacterial colonisation was completely eradicated’ for all four mice (100% reduction)
Fukada et al 37 2008Total bacterial loadCotton cellulose sheet dampened with ethyl alcohol—intervention only conducted in the OR Mean bacterial counts (SD):
OR: 333 (141)
ICU: 1015 (501)
Consulting room and OPD reception area: 1113 (1420)
In the OR: mean (SD) total bacteria counts reduced significantly (from 333 [141] to 35 [67] CFU/mL)
P<0.05
Gostine et al 39 2016Total bacterial loadUV Angel desktop lamps, set to 3-min, 5-min, 6-min and 10-min cycles193/203 (95.1%) samples, median of 120 CFUs per keyboard13/218 (6%) samples contaminated, a >99% reduction based on median CFU values (120 pre, 0 post). P<0.0001
Jones et al 47 2015Total bacterial load“CHG spray” (chlorhexidine gluconate and isopropyl alcohol) versus “TF spray” (chlorine dioxide based)57% of keyboards had contamination of >500 CFU
(Included: Bacillus spp., CNS, micrococci and diphtheroids)
2% of keyboards had contamination of >500 CFU (p≤0.001)
(Only bacterial isolate was Bacillus spp.)
Martin et al 57 2011Total bacterial loadKeyboards with Vioguard UV light irradiation versus identical control keyboards not exposed to UV light irradiation23/24 (96%) had bacteria isolated8/24 (33%) had bacteria isolated. P=0.001
(Primarily Gram-positive human flora and Gram-negative environmental flora. S. aureus and P. aeruginosa isolated from two control keyboards)
Messina et al 58 2013 (A)Total bacteria count of:
Staphylococci, E. coli, Pseudomonas, total coliform bacteria, Acinetobacter and C. diff
Putty cleaning compound (ethanol 29%) with malleable-elastic consistencyTotal microbial load (at two different incubation temperatures):
36°C: 26/27 (96.3%), CFU: 512
22°C: 25/27 (92.6%), CFU 557
Acinetobacter spp.: 1 (3.7%)
E. coli: 11 (40.7%)
Coliforms: 21 (77.8%)
Enterococci: 4 (14.8%)
Staphylococci: 25 (92.6%)
MRSA: 6 (22.2%)
Moulds: 20 (74.1%)
36°C: 2/27 (7.4%), CFU: 3
22°C: 4/27 (14.8%), CFU: 18
Significant reductions in:
Coliforms: 2 (7.4%), p<0.0001
Staphylococci: 1 (3.7%), p<0.0001
Moulds: 1 (3.7%), p<0.0001
E. coli: 0%, p=0.001
Borderline or non-significant reductions in:
Enterococcus 0%: p=0.045 and
MRSA 0%: p=0.014
Messina et al 59 2013 (B)Total bacterial loadPutty cleaning compound (ethanol 29%) with malleable-elastic consistencyTotal microbial load (at two different incubation temperatures):
36°C: 49/50 (98%)
22°C: 33/50 (66%)
E. coli: 17/50 (34%)
Coliforms: 39/50 (78%)
Enterococci: 5/50 (10%)
Staphylococci: 47/50 (94%)
MRSA: 8/50 (16%)
Moulds: 26/50 (52%)
36°C: 8/50 (16%)
22°C: 8/50 (16%)
Coliforms: 1 (2%)
Staphylococci: 2 (4%)
Moulds: 1 (2%)
Significant differences for all (p<0.001) after disinfection
Neely et al 63 1999Detection of Acinetobacter speciesEnhanced cleaning policy: required to wear gloves before using computer and  plastic keyboard covers cleaned daily13 acquired colonisations and 16 total colonisations of A. baumannii in 5 months preintervention10 acquired colonisations and 34 total colonisations of A. baumannii in 19 months postintervention
The number of acquired A. baumannii colonisations postintervention were significantly less than preintervention (p<0.05)
Patel et al 67 2010Total bacterial load70% isopropanol wipes versus Virkon (dipotassium peroxodisulfate)100% contaminated with bacteria including S. aureus, coagulase-negative staphylococci, Gram-negative rods and cocci100% of C. albicans, P. aeruginosa and S. sanguinis removed
99.9% of S. epidermidis removed
96% of all the other organisms removed
The number of organisms recovered after the intervention were significantly reduced (p<0.001)
Shaikh et al 77 2016Total bacterial loadUV Angel system20/25 (80%) contaminated with any potential pathogen, including Gram-negative bacilli, C. diff, Enterococcus or S. aureus 5/25 (20%) contaminated with any potential pathogen (p=0.0001)
Total aerobic and facultative bacteria: 18/25 (72%) (p=0.0006)
Wilson et al 87 2008Detection of S. aureus and Acinetobacter spp.Medigenic keyboard (alarm when cleaning required), anonymous keyboard, versus standard keyboardsFor Medigenic keyboards, baseline contamination rates ranged from 38 to 65 CFU, depending on alarm interval. Included: MRSA and AcinetobacterTotal viable count on Medigenic keyboards with alarm lower than other two types of keyboards. Median CFU reduced from 38 to 5. P<0.0001
Xu et al 89 2017Detection of MRSACotton cloth and bucket system versus disinfectant wipes7/19 (36.8%) keyboards and mice positive for MRSA2/206 (1%) positive for MRSA. P<0.001
  • A. baumannii, Acinetobacter baumannii; C. albicans, Candida albicans; C. diff, Clostridium difficile; CFU, colony forming unit; CNS, coagulase-negative staphylococcus; E. coli, Escherichia coli; ICU, intensive care unit; MRSA, methicillin-resistant Staphylococcus aureus; OPD, outpatient department; OR, operating room; P. aeruginosa, Pseudomonas aeruginosa; S. aureus, Staphylococcus aureus; S. epidermidis, Staphylococcus epidermidis; S. sanguinis, Streptococcus sanguinis; UV, ultraviolet.