Rae Ellen Bichell of NPR writes that a majority of working adults say they still go to work when they have a cold or the flu. There are some jobs where doing that can have a big effect on health. At least half of people who work in very public places, like hospitals and restaurants, report going to work when they have a cold or the flu. Those were among the findings of a poll conducted by NPR, the Robert Wood Johnson Foundation and the Harvard T.H. Chan School of Public Health. They are some of the last people you’d want to go to work sick, because they tend to have a lot of contact with people. And that helps spread disease. “It’s one of the biggest food safety problems that there is, and we’ve known about it forever,” says Kirk Smith, who oversees foodborne outbreak investigations with the Minnesota Department of Health. But he says it’s really hard to get people to stop doing it. When it comes to food handling, there’s one illness that’s particularly concerning: norovirus. “It is by far the most common cause of foodborne illness,” says Smith. According to the Centers for Disease Control and Prevention, the virus is responsible for 35 percent of them. That’s because there are billions of virus particles per gram in stool and vomit. It only takes about 20 of those to get someone sick. And norovirus can hitchhike from surface to surface. It takes a high concentration of bleach to kill it. “And so it just takes microcontamination of your hands, if you don’t do a perfect job washing, to be able to contaminate food with enough of the virus to infect lots and lots of people,” says Smith. The same virus has plagued restaurant customers across the country. Last winter, 140 people — including much of the Boston College basketball team — got sick from eating at a Chipotle in Boston where one person had gone to work sick. “It’s definitely the norm to go into work sick. That’s what I and most of my co-workers usually do,” says Anthony Peeples. He used to work at an Olive Garden restaurant. Now he’s a bartender at a casino in Michigan City, Ind. The CDC has found that 1 in 5 food service workers has reported working while sick with vomiting and diarrhea.