Bacteria Can Quietly Thrive on Computer Keyboards

It's enough to make you want to scrub your hands and hose down your computer.

While you type, your fingers could be grazing over potentially harmful bacteria. That news comes from Gary Noskin, MD, and colleagues at Chicago's Northwestern Memorial Hospital.

They were curious to see if bacteria found a friendly home on computer keyboards and if those bacteria could then hop onto someone's hand, given the chance.

All three of the germs they tested survived at least an hour on the keyboards. Two lasted for a day and grew during that time.

Bad Bugs

The bacteria tested were vancomycin-resistant Enterococcus faecium (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa (PSAE).

All three bacteria are widespread in nature. In a worst-case scenario, they can be life-threatening, but they rarely bother healthy people, says a news release from the Society for Healthcare Epidemiology of America.

VRE and PSAE usually only trouble hospitalized patients whose immune systems are compromised, says the news release. VRE can cause complicated abdominal infections, as well as infecting the skin, bloodstream, and urinary tract. PSAE frequently prompts pneumonia, urinary tract infections, and bloodstream infections.

MRSA, a staph infection, can cause skin rash, boils, blisters, toxic shock syndrome, and other types of infection. Unlike VRE and PSAE, it's more likely to spread outside hospitals, usually through an open wound or other skin infection. Infections of antibiotic-resistant staph -- also called "superbugs" -- have recently popped up in otherwise healthy people, says the release.

Bacteria Survive, Thrive on Keyboards

In the study, clean computer keyboards and keyboard covers were contaminated with the three bacteria.

MRSA and PSAE lived and grew there for 24 hours. VRE was a little less hardy. It only lasted for an hour on the keyboards and no more than five minutes on keyboard covers.

The researchers found people to touch the computer keyboards and covers. The volunteers' gloved or ungloved hands often picked up the bacteria.

"After any contact with computer keyboards, both gloved and ungloved hands frequently became contaminated," the researchers told a meeting of the Society for Healthcare Epidemiology.

Swabbing the Decks

If your skin is starting to crawl, know that it's possible to get rid of the bacteria.

Two germicides made for keyboards were tested. According to the products' instructions, one germicide takes 10 minutes to do its job; the other takes five minutes.

Both successfully disinfected the keyboard. But only the 10-minute germicide killed the bacteria on the keyboard covers. "VRE and PSAE were still present on the covers after five minutes," says Noskin's study.

In real life, those bacteria might not be on your computer keyboard. But who knows what's on your keyboard? Ever sneeze or cough over it? See any crumbs down there between the keys? And come to think of it, when was the last time you cleaned your computer?

Follow manufacturers' directions for cleaning your computer without damaging it.

Wash Your Hands

"While it's important to disinfect computer equipment on a regular basis, the most important disease prevention strategy is to wash your hands prior to patient contact," Noskin tells health care workers in the news release.

You don't have to be a doctor or nurse to follow that advice. Keeping hands clean is a good way for anyone to keep germs at bay.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: 15th Annual Scientific Session of the Society for Healthcare Epidemiology of America, Los Angeles, April 9-12, 2005. News release, Society for Healthcare Epidemiology of America.