Disneyland is famous for teacup rides, exotic castles, smiling cartoon characters come to life—and now, spreading highly infectious diseases.  

Over 54 people—including five Disneyland employees—have been infected with measles since an outbreak at the amusement park last month. Rumors on social media pointed the finger initially at undocumented immigrants, but the high numbers of patients without complete vaccination records suggests that parents who chose not to vaccinate their children are actually the ones to blame. 

Electing not to vaccinate is a common practice in wealthy communities in southern California, where vaccine refusal rates range from 5.5 to 13.5%

"There are parts of affluent Los Angeles county that have lower vaccination rates...than third world countries," said homeland security expert Juliette Kayyem on Boston Public Radio.

In a highly-dense public space like Disneyland, she explained, the choice not to vaccinate metastasizes quickly from a personal decision to a public health issue. 

"I love my children, and I believe people who choose not to vaccinate their children love their children too," Kayyem said. "But I love their children more than they love mine."

Indeed, unvaccinated people are 35 times more likely to catch measles and transmit it to others, which is especially dangerous when they're in the presence of children who are too young to be vaccinated. That means parents who choose not to vaccinate their children are putting the children of others at a serious risk for fears that have little to no basis in scientific evidence.

"Even if you can argue that there is some risk for vaccination—of which the science is small—we live in a society in which we have reduced public health harms where the rest of the world looks at us in envy," Kayyem said.

"If you believe in science, if you believe in medicine, we are a better world, we are a much better nation, because of vaccination and public health efforts," she said.

To hear more from homeland security expert Juliette Kayyem, tune in to her full interview on Boston Public Radio above.