Why your sick co-worker insists on coming in

If it seems like there's an epidemic of workers insisting on schlepping into the office despite looking green and popping cough drops, you're right. 

One-quarter of American workers say they always go to work while sick, according to a survey from public health company NSF International. Another one-third admit to waiting until their symptoms are full blown until deciding to stay at home. 

Working while sick is increasingly coming under scrutiny by workers' advocates, who note that there are no federal requirements for employers to provide paid sick leave. Failing to provide paid sick days is a public health issue, as that incentivizes ill workers to show up for work or send a sick child to school, which can spread disease, according to a report for the National Partnership for Women & Families. 

Almost 40 million U.S. workers lack paid sick leave, the National Partnership for Women & Families notes. Its report found that almost one-quarter of adults have either lost a job or been threatened with firing for taking time off to deal with an illness or a sick dependent.

Nevertheless, the biggest reason why employees insist on going to work while being sick is the fear of missing deadlines, with 42 percent of respondents citing heavy workloads. 

Lost wages or financial issues was the second most common reason for working while sick, with 37 percent noting that they couldn't afford to be sick. 

Interestingly, one-quarter of respondents said their bosses expect them to work sick. That doesn't jibe well with co-workers, however, as 57 percent said they would tell a colleague to go home if she or he turned up sick. Another one-quarter of workers are willing to tell sick colleagues to stay out of their workspace. 

While workers don't want to catch their colleagues' germs, the majority said they view sick employees as "hard working."

"Only 16 percent of workers felt that colleagues who came to work sick were selfish and didn't care about the well-being of their co-workers, and 13 percent believed co-workers come to work sick because they don't trust their colleagues to do the job while they are out," NSF said in a statement. 

Some states and cities have either passed laws to require employers to pay for sick days or are mulling legislation. San Francisco became the first U.S. locality to pass such a law, while cities such as Milwaukee and Seattle followed. Still, Connecticut is the only state with mandated paid sick time. Other states are contemplating legislation, including Arizona and New York. 

Employers are often divided on providing paid sick days, The Wall Street Journal noted earlier this month.

"When you're hiring part-time retail individuals, it's hard to cultivate a culture where they're really loyal," one employer told The Journal. "If someone says they're sick, are they really sick? Hopefully you get the right behavior."