Methicillin-resistant Staphylococcus aureus contamination of hospital-use-only mobile phones and efficacy of 222-nm ultraviolet disinfection

Abstract

Background: Mobile phones may be contaminated with nosocomial pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). The aim of this study was to investigate the MRSA contamination rate on doctors' hospital-use-only mobile phones and the efficacy of 222-nm ultraviolet light (UV) disinfection. Methods: We investigated the MRSA contamination rate of doctors' hospital-use-only mobile phones, as well as the reduction in MRSA counts on plastic plates and aerobic bacteria (AB) on mobile phones before and after exposure to 222-nm UV irradiation. Results: Five (10%) of the 50 mobile phones investigated were contaminated with MRSA. Exposure to 0.1 mJ/ cm 2 222-nm UVC irradiation for 1.5 and 2.5 min (9 and 15 mJ/cm 2) achieved mean log 10 MRSA colony-forming units reductions of 2.91 and 3.95, respectively. Exposure to 9 mJ/cm 2 222-nm UVC irradiation (0.1 mW/ cm 2 for 1.5 minutes) significantly reduced AB contamination on mobile phones (P < .001). Conclusions: The use of 222-nm UV disinfection resulted in effective in vitro reduction of MRSA and significantly reduced AB contamination of mobile phone surfaces.

One‐year Ocular Safety Observation of Workers and Estimations of Microorganism Inactivation Efficacy in the Room Irradiated with 222‐nm Far Ultraviolet‐C Lamps

“…Accordingly, differences in particle diameters can explain the different efficacies of inhibition between bacteria and phage observed in our study. Disinfection by 222‐nm UV‐C was effective for MRSA and aerobic bacteria contamination on doctors' hospital‐use‐only mobile phones (39). Our study suggested the possible inactivation efficacy for microorganisms by 222‐nm irradiation on the desk surfaces where the PC keyboards were located, the table where the slitlamp microscope was there, and the floor where the device's footswitch was there in the full‐room UVGI settings.…”

Effect of intermittent irradiation and fluence-response of 222 nm ultraviolet light on SARS-CoV-2 contamination

“…The Care222™ (Ushio Inc., Tokyo, Japan) UVC-emitting device used in this study was a 222 nm Kr–Cl excimer lamp module. The lamp contains an optical filter that restricted spectra-emitting light ranging between 200 and 230 nm, of which the maximum output wavelength was 222 nm [ 7 , 8 ]. To evaluate the differences in the effect of the continuous and intermittent irradiation of 222 nm UVC on SARS-CoV-2 inactivation, we experimented with 5 min of continuous and intermittent irradiation for 0.1, 0.05, 0.013 and 0.003 mW/cm 2 of 222 nm UVC.…”

Microbiological Contamination of Mobile Phones and Mobile Phone Hygiene of Final-Year Medical Students in Uganda: A Need for Educational Intervention

“…[11][12][13][14][15][16][17][18] Furthermore, studies have shown that bacteria isolated from mobile phones are MDR. 19 A study carried out in Ethiopia found an overall prevalence of 69.9% MDR bacterial isolates. 12 Consequently, contaminated mobile phones, being one of the most highly touched surfaces, act as reservoirs for organisms and may play a role in the spread of HAI caused by MDR organisms in the hospital setting and the community.…”