When you take a sick day from work, you’re not just saving yourself from misery—you’re also preventing colleagues from catching your condition. But according to a new National Bureau of Economic Research (NBER) paper, The Wall Street Journal reports, half of American workers aren’t granted compensated absences. This means they end up going to work while ill. If they did receive paid time off and were therefore able to stay home with the sniffles, the study’s authors conclude, the general flu rate would be greatly reduced [PDF].

Individuals who don’t receive paid sick days are the people who can least afford to forego a day’s wages to stay in bed. According to Labor Department data from 2015, only 31 percent of the lowest-earning quarter of private-sector workers were granted paid sick leave. In contrast, 84 percent of the highest-earning quarter had it. 

Some cities and states, including Oregon, California, and Vermont, have passed paid sick day laws. To see if these measures really lowered incidents of public illness, NBER researchers compared regions with paid sick leave to Google Flu data from 2003 to 2015. Their findings shouldn’t be too surprising to anyone who’s battled a nasty office bug: As The Cut notes, paid leave prevented 100 cases of flu-like viruses each week for every 100,000 people. Overall, that’s a 6 percent decrease in flu cases among the population level.

Of course, everyone’s known a worker who’s taken a sick day even when they weren’t ill (or you’ve even done it once or twice yourself). NBER’s paper did find that more healthy people play hooky from their jobs when they’re granted paid sick leave. But still, the researchers point out, it’s a tradeoff. Only 40 percent of people in the US have flu vaccinations—and if they work while sick, they’re likely to infect others.

Have plenty of paid sick days stored up, and don’t think this study applies to you and your colleagues? Think again. As Time points out, many low-income workers who don’t have access to paid sick leave work in retail or food service. If you go shopping or eat at a restaurant, you might end up contracting the flu from them—not your cubicle mate.

[h/t The Wall Street Journal]

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