It’s back. Three years after public health officials realized that they had been premature in declaring that measles was eliminated in the U.S., new outbreaks of the highly infectious disease are once again cropping up in cities across the country. And it would be a mistake, epidemiologists warn, not to take this extremely seriously.

As expected, the outbreaks have caused plenty of outrage directed against Jenny McCarthy and the crowd of parents who refuse to vaccinate their children. Writing in the Daily Beast, a pediatrician using the pseudonym Russell Saunders calls it “sheer lunacy”: “Just over a dozen years ago this illness was considered eliminated in our country,” he writes, “and this year people are being hospitalized for it. All due to the hysteria about a safe, effective vaccine. All based on nothing.”

But for the most part, the outbreaks are also being treated as a cautionary tale - an opportunity to chide anti-vaxxers while reminding parents to make sure that their children are up-to-date on their shots, as KJ Dell’Antonia does at the New York Times’ Motherlode blog:

This outbreak could serve as a reminder that we vaccinate our children, and ourselves, for our own protection and for the protection of our community. A spokesperson for New York-Presbyterian Hospital/Columbia University Medical Center said that the hospital is notifying 600 people who might have been exposed there (in what it calls “probably an excess of caution”). If the majority of those 600 people were not vaccinated, The Times could soon be running a very different article on its front page. Fortunately, statistics suggest that most of those 600 people will have been vaccinated against measles, and 95 percent of them will be immune as a result. That’s lucky for us all, including those who have made a different choice for their children.

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