Or maybe you’re in an unfamiliar neighborhood and want to explore. You pull out your phone, pull up Yelp or Open Table or Urban Spoon, and find a promising place to nosh.

And a few hours or days later, you feel sick, and want to punish the place you think is responsible by giving them a lambasting, single-star review. But you don’t want to be that person. So you don’t.

Next time, rethink that impulse. You could be helping a lot of people—and not just by warning them off a dodgy dish.

Today, in its weekly news bulletin, the Centers for Disease Control and Prevention reports on an innovative project that the New York City health department tried out for nine months