To The Editors:
Since November, 1996, the pediatric intensive care unit at Royal Alexandra Hospital for Children, Westmead, New South Wales, has switched entirely to computerized records. There have been recent problems with burn patients on the unit becoming colonized with methicillin-resistant Staphylococcus aureus and with apparent patient-to-patient transmission of extended spectrum betalactamase-producing Klebsiella pneumoniae. Both organisms are most likely to be transferred on the hands of staff.
In discussions on ways to prevent spread of these resistant organisms by improving hand-washing, the possibility was raised of contamination of computer keyboards by the staffs' hands. To test this hypothesis a team from microbiology and infectious diseases swabbed every keyboard on a single day. All keyboards have a plastic cover, and this is cleaned with disinfectant every morning at about 9 a.m. It was decided to swab the keyboards at 3 p.m. after staff had been working there for 6 h. Cotton swabs were dipped in sterile saline, then used to swab all the keys on the board and placed in Stuart's transport medium. At the laboratory they were plated onto horse blood agar, mannitol salt agar and MacConkey agar. Pathogens were identified by standard techniques.
Twenty-seven keyboards were swabbed, of which 12 were in active patient use, 8 were in a central area used by many staff and 7 were in bed areas not in active patient use at the time. The main growth was of coagulase-negative staphylococci from 25 keyboards. Two keyboards grew S. aureus, both of which samples were susceptible to methicillin/flucloxacillin. One terminal grew Pseudomonas which was not speciated.
We conclude that we could find no evidence that computer keyboards were a significant source of spread of resistant bacteria.
David Isaacs, M.D.
Andrew Daley, M.B.
Dianne Dalton, R.N.
Robyn Hardiman, M.B.
Revathy Nallusamy, M.B.
Departments of Infectious Diseases and Microbiology; Royal Alexandra Hospital for Children; Westmead, NSW, 2145 Australia