Maine Referendum Targets Vaccine-Exemption Limits

On Super Tuesday, voters will decide whether to overturn new law halting nonmedical exemptions

With measles outbreaks continuing to rise as the summer travel season heats up, WSJ’s Lorie Hirose takes a look at state vaccination laws and what the Centers for Disease Control and Prevention is doing to fight the disease. Photo Illustration: Laura Kammermann

Maine residents heading to the polls on Super Tuesday will decide whether to override a new law that eliminates nonmedical vaccine exemptions for school children.

Supporters of the law say limiting the ways in which people can opt out of vaccines will help keep preventable diseases like measles at bay by curbing a growing rate of unvaccinated children.

Democratic...