The average office has hundreds of times more bacteria than a toilet seat, and women spread more germs in the workplace than men.
The average office has hundreds of times more bacteria than a toilet seat, and women spread more germs in the workplace than men. (Associated Press)

The average office has hundreds of times more bacteria than a toilet seat. The "enter" button on your office fax machine is probably a rank stew of vile bacteria.

Those are some of the findings of America's leading expert on work and home hygiene, Charles Gerba, a professor of microbiology at the University of Arizona.

Over the past two years, Gerba and his team have seen an improvement in overall office hygiene as desk wipes and hand cleaners become more popular.

However, in these summer months, with air conditioning units and ventilation shafts a good breeding ground for bacteria, there are a number of points experts want you to be aware of before you high five a college friend at the office meeting:


Washing your hands for 20 seconds under soap and running water is far better than a quick squirt of hand sanitizer at your desk, said Dean Cliver, a professor of food safety at the University of California.

While many hand sanitizers boast of anti-microbial properties, a scrub with ordinary soap is far better, Cliver said. Water penetrates much deeper, helping to remove food debris and other particles that hand sanitizer just doesn't reach.


Gerba's research in dozens of offices has found that the "enter" and "send" buttons on fax machines carry some of the highest concentrations of harmful microbes. In contrast, lesser used keys have significantly less contamination.

Other commonly used surfaces with high contamination levels include the "copy" button on the office copier, and the handles of restroom doors.


Shake an average office keyboard and you are likely to find what Gerba calls "the bagel shower" - bits of bread particles and other food bites lodged between the keys.

Most office cleaning companies do not touch computers or keyboards because they don't want to risk causing any damage. Hygiene is left to the employee, and many don't bother.

Gerba recommends an alcohol- based sanitizer for cleaning the keyboard. Simply blowing compressed air over it is not going to remove bacteria clinging to the surface, he warned.

Perhaps the best combination is that used by Brendan Cahalan, a risk manager with Standard Motor Products in Long Island City in New York. He uses an alcohol-based cleaner on his computer, as well as compressed air to clean out any debris between the keys.


Office workers touch their hands to their faces an average of 18 times an hour, according to Elizabeth Scott, a professor at the Simmons Center for Hygiene and Health in Boston.

When we touch our faces, we bring all the collected gunk of our keyboard, desktop or BlackBerry right to our respiratory and digestive system every three and a half minutes - bacteria and viruses couldn't ask for a better transportation system.

Scott recommends washing hands regularly and, yes, using hand sanitizer, especially after shaking hands with a colleague suspected of having a cold or another illness. "As soon as I see someone come into my office that I think is sick, I immediately grab the sanitizer. You can shake hands at business meetings and still protect yourself," she said.

Gerba, in contrast, politely declines a handshake if someone has a cold. "You could infect the whole office. Any reasonable person will understand," he said.


Gerba's study of offices in New York, San Francisco and Tucson, Ariz., found that teachers' offices had by far the highest levels of germs per square inch, nearly three times as much as bankers, the next-most-contaminated professionals. Lawyers had the least infection. While lawyers have the advantage of having little contact with children, they are also good at sticking to a regimen, Gerba said.

One example is Colleen Kerwick, an aviation litigation attorney with a firm in Manhattan. She wraps up food remains and dumps them immediately. She was encouraged to do so after seeing a mouse's head peer out of a waste basket at a previous employer's office.

"I do not use hand sanitizers or antibiotics as I believe they weaken your immune system." she said.


Here's a controversial bit to the Charles Gerba's study - women spread more germs in the workplace than men. Before women take offense, the higher germ concentration is proof that women have a healthier diet than men.

Women, Gerba found, tend to store apples, bananas and other biodegradable, healthy food at their desk while men go for less nutritious and therefore less germ-ridden junk. The fresh food provides a boon for bacteria.

One recommendation? Don't let food accumulate in your desk drawer, where it will be a giant breeding ground for bacteria.

Gerba recommends the rapid disposal of any unwanted food; hassled employees often forget about food at the back of drawers.

"The office refrigerator is a total mess as well," he said. "People do not keep to the disposal rules, and the refrigerator is taking in food from many, many different households."


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