The U.S. is known for being the “no vacation nation,” but apparently we also don’t like taking sick days.

According to the Flu Season Survey from Staples, 90% of employees admit they have come into the office despite knowing they are sick—an increase of 10% from last year. What’s worse, workers recognized staying home with the flu for three days was appropriate, but most of us only stay away for two days with 45% of respondents saying they didn’t want to fall behind on their work.

But Dr. George Kikano, a family practitioner at UH Case Medical Center in Cleveland, advises workers to put their health first and realize that calling out sick won’t necessarily reflect poorly.

“Everyone gets sick: the boss will get sick and those on the front level will get sick, no one is immune and companies recognize this and for the most part, have generous sick leave.”

He adds that employers should encourage workers to stay home and rest at the first sign of an illness.

“Study after study has shown that rest has a healing effect and can bring a sickness to only lasting three or four days from five or seven.”

Flu season can be detrimental to a company’s output since each year it causes an estimated 70 million missed workdays and billions in lost office productivity, Lisa Hamblet, vice president for facility solutions at Staples Advantage, said in a statement.

For workers trying to stay healthy this year, they should try and avoid the break room, which according to the survey, is the dirtiest place in the office. Employees should also keep in mind that flu viruses can live on a hard surface for up to three days and should be proactive with cleaning their desks and phone to avoid getting sick.

As we head into cold and flu season, there are steps workers can take to avoid getting sick and according to Kikano, one of the best ways to stay healthy is diligent hand washing.

“Washing your hands, especially during this time of year, is the single most effective way to avoid getting sick,” he says.

Dr. Hansa Bhargava of WebMD.com recommends cleaning your workspace including telephone, keyboard and commonly-touched places like water fountain handles or microwave door handles to avoid getting sick. "Avoid touching your eyes, nose, or mouth. Cold and flu germs can often spread if you touch something that is contaminated then touch your eyes, nose, or mouth."

Here are three signs that it might be time to call in sick:

You Have a Temperature. Everyone has a different temperature threshold, but experts say a temperature higher than your normal one is reason to call in sick--especially if it's a sudden fever.

You have Secretions. If you are coughing up phlegm, have a runny nose or are sneezing frequently, it’s time to say home.

“Anything that means germs are coming as air droplets from your body can be potentially contagious to your coworker,” says Kikano.

Extreme Fatigue or Body Aches. Doctors say outside symptoms of the flu, like coughing or sneezing, don't materialize right away and instead the illness starts with extreme fatigue, body aches, cough or chills.

"If you begin to have these symptoms it could be best to stay home and contact your physician," says Bhargava.

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