"Presenteeism" is the term researchers have come up with to describe workers turning up to work when they're sick. Unsurprisingly, these workers tend to be less productive than their healthy co-workers and might make their colleagues sick in the process. There's no standard for measuring how much productivity, exactly, is lost to sick workers on the job, but a number of studies have ballparked it to be between 20 and 60 percent of a given company's health-care costs, according to the Harvard Business Review.
People who turn up to work with contagious diseases can be particularly problematic for companies. If Costas's pink eye happens to be the bacterial version and you happen to be one of his producers, you might want to think about running in the other direction (or at least washing your hands. A lot.). Bacterial pink eye is quite contagious!
As to why people go to work when they're sick, it's pretty much what you'd expect. One large-scale study of 11,270 working people in Denmark found that people who described themselves as "over-committed" to work were mostly likely to turn up sick. Given that Costas has hosted the Olympics for 26 years straight, its fair to guess he might fall into this category. Level of pay, however, did not show any association between those more or less likely to contribute to presenteeism.
In the United States particularly, a lack of paid sick days can also be a factor. While most other countries guarantee a certain amount of sick leave, one recent study found that 38 percent of American workers do not have that type of benefit. This is likely not a problem for Costas as he lives in New York City, which has a law requiring all companies with 20 or more employees to offer paid sick leave.
So, congratulations to you, Mr. Costas, on your bold stand against presenteeism -- and we hope your pink eye gets better very soon.