Keyboards harbour nasty bugs

Apr 11 2005

A new study has shown that some nasty bacteria can survive and grow for at least 24 hours on computer keyboards and electronic recordkeeping in hospitals and other health care settings and may be spreading more than just information.

A team of researchers from Northwestern Memorial Hospital in Chicago were concerned that the keyboard and keyboard covers used on many machines might serve as a reservoir for drug resistant bacteria that are of concern in a health care environment.

Dr. Gary Noskin, medical director of healthcare epidemiology and quality at the hospital says they have shown that some bacteria can survive for a long time on keyboards and it is possible to transmit them from the keys to the fingertips and potentially pass them along through contact with other patients. The national trend in hospitals is to have computerized order entry, which often means computers in patients rooms, in places that are in direct close contact with patients.

His team "inoculated" keyboards and covers with three types of bacteria commonly found in hospitals - vancomycin-resistant enterococcus (VRE), methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PSAE) and they found the first two bugs continued to grow for at least 24 hours but PSAE could be recovered only up to one hour on keyboards and five minutes on the keyboard cover, Noskin said.

VRE and PSAE rarely cause problems for anyone other than hospitalized patients whose immune systems are sometimes compromised, but antibiotic-resistant staph infections to the skin are becoming more common both in hospitals and community settings. Although the team only studied the hospital setting, Noskin is sure that no keyboard anywhere is sterile and people using them in libraries and schools or offices need to remember that, particularly if they have any kind of breaks in their skin that could allow bacteria to penetrate.

The researchers found that volunteers who typed on the contaminated keyboards had more likelihood of the bacteria winding up on their hands the more contact they had with the keyboard, up to a 92 percent transmission rate for the staph germs, 50 percent for VRE and 18 percent for PSAE. It was discovered that gloves and keyboard covers which was assumed would help minimize the risk for this kind of exchange was not necessarily so as they too became contaminated.

Washing the equipment with hospital disinfectants heavy on ammonia killed the germs after it was left on for five to 10 minutes but has dire implications for the electronic circuits beneath the keys, more research is needed on how to disinfect both computer keyboards and handheld devices that many doctors carry with them on rounds.

Noskin emphasises that while it is important to disinfect computer equipment on a regular basis, especially in a healthcare environment, the most important disease prevention strategy is to wash the hands prior to patient contact. He says keyboards are like any surface in the hospital and if they're out in the environment, they can become contaminated with all the bugs that are in that environment.

He presented the findings from the study before the annual scientific session of the Society for Healthcare Epidemiology of America being held this week in Los Angeles.