When an employee comes out and communicates feelings of stress, the floodgates can open and the number of coworkers with similar symptoms, perceived or otherwise, will also step forward, multiplying the overall levels of stress reported, according to studies made by the U.K.'s Health and Safety Executive (HSE).

Dr. Jo Rick, principal research fellow at the Institute for Employment Studies (IES), says many of the studies show that management culture and style are major causes of stress. Non-supportive environments are breeding grounds for contagious stress, she says:

There is another type of "domino effect" at work with stress when it is brought into the open, according to U.K. researchers. Stress can spread through an office quickly when the workloads of employees absent due to stress-related ills are redistributed among the team, leading to more pressure, which can result in stress-related illnesses.

Figures from the International Stress Management Association U.K. suggest that more than a third (36 percent) of workers believe that stress is reducing their productivity.