Perhaps the sound of sneezing and sniffling doesn't reach the corner office because, according to a recent survey, many managers don't realize how often their employees are coming into work sick.

Of the 522 office workers surveyed by the staffing service, OfficeTeam, 45 percent of respondents said that they "very frequently" go to work when they're feeling sick, while only 17 percent of 150 managers polled thought that this was common practice.

"It's a sign that employers may be out of touch with what's going on with their employees," says Brandi Britton, senior regional vice-president of OfficeTeam.

Some employees are reluctant to use up vacation days to stay home, while others might not be able to spare that day's pay. According to a 2006 study by the Society for Human Resource Management, nearly one-third of companies do not offer any paid sick leave.

And now, as companies nationwide slash their staffs to keep afloat in the down economy, the pressure to show up no matter what is even higher. "Individuals are fearing layoffs," says Britton, "They don't want to be not visible."

But sometimes toughing it out and coming in under the weather can do more harm that good – for the individual and the company. "Presenteeism actually costs businesses more than absenteeism," says Rosyln Stone, chief operating officer of Corporate Wellness Inc., a workplace health services provider.

"People make more mistakes, and it can take them twice as long to complete a task," she says. In one recent study, health researcher Walter Stewart found that productivity decreases, due to presenteeism, cost American businesses more than $150 billion dollars a year.

The OfficeTeam report suggests that managers looking to avoid these costs and boost overall workplace health can lead by example (not come in sick themselves), clarify absenteeism policies, and accommodate telecommuting so that employees who are sick can still contribute from home.