As the measles outbreak continues to spread, political leaders with an eye on the White House in 2016 spent much of the week jumping into, and then trying to bail themselves out of, the vaccine debate.
Some brushed the issue off as an unnecessary media circus, but it's worth taking a look at its deeper political meaning. Here are five things the vaccine politics kerfuffle of 2015 tells us about the emerging field of presidential candidates for 2016.
1. Vaccination politics are a problem for Republicans — not Democrats.