Summary
Introduction
Healthcare environmental surfaces may be contaminated with micro-organisms that cause
healthcare-associated infections (HCAIs). Special attention is paid to near-patient
surfaces but sites outside the patient zone receive less attention. This paper presents
data on keyboard contamination and the risk of pathogen transmission from keyboards.
Methods
Keyboards from nursing stations in three hospitals and a dental practice were analysed
for bacterial contamination. Surfaces were pre-treated to remove planktonic bacteria
so that any remaining bacteria were presumed to be associated with biofilm. Bacterial
transfer from keyboard keys was studied following wiping with sterile water or sodium
hypochlorite. The presence of multi-drug-resistant organisms (MDROs) was sought using
selective culture.
Results
Moist swabbing did not detect bacteria from any keyboard samples. Use of enrichment
broth, however, demonstrated MDROs from most samples. Gram-negative bacteria were
recovered from almost half (45%) of the samples, with meticillin-resistant Staphylococcus aureus, vancomycin-resistant enterococcus and MDR Acinetobacter spp. recovered from 72%, 31% and 17% of samples, respectively. Isolates were transferred
from 69% of samples after wiping with sterile water, and from 54% of samples after
wiping with 1000 ppm sodium hypochlorite.
Discussion
While moist swabbing failed to detect bacteria from keyboards, pathogens were recovered
using enrichment culture. Use of water- or NaOCl-soaked wipes transferred bacteria
from most samples tested. This study implies that hospital keyboards situated outside
the patient zone commonly harbour dry surface biofilms (DSBs) that offer a potential
reservoir for transferable pathogens. While the role of keyboards in transmission
is uncertain, there is a need to pursue effective solutions for eliminating DSBs from
keyboards.
Keywords
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Article info
Publication history
Published online: February 26, 2021
Accepted:
February 21,
2021
Received:
February 3,
2021
Identification
Copyright
© 2021 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
