Love this post from Ezra.  I'm just going to borrow it:

"About 40 percent of all private-sector workers do not receive paid sick days," reports the New York Times, "and as a result many of them cannot afford to stay home when they are ill. Even some companies that provide paid sick days have policies that make it difficult to call in sick, like giving demerits each time someone misses a day."

This isn't just inhumane policy. It's stupid policy. We're facing a new strain of flu that most have zero resistance against. Workers who fall ill but nevertheless have to ride the bus in to work and stock shelves and talk to co-workers and ride the bus home aren't just workers having a bad day, or workers at risk of getting really sick. They're contagious. They're spreading the flu to other workers, who will in turn be contagious, even to richer workers who do get sick days.

The downside is not simply that lots of people get the flu. It's that the flu has more opportunities to mutate into something more lethal, or more contagious. The reason public health officials urge people to stay home is to deny the illness opportunities to mutate, but the warnings of public health officials are nothing compared with the pressures of an employer that doesn't tolerate sick days. This, incidentally, is not a problem other countries will face. As this Center for Economic and Policy Research report explains, the United States is the only advanced economy in the world that doesn't guarantee its workers paid sick days.