The recent measles outbreak that originated at Disneyland has demonstrated just how vulnerable to preventable diseases the population is when parents refuse to have their children vaccinated, Vox reports.

In Orange County, California — where Disneyland is located — almost 10 percent of parents request a vaccination exemption for their children.

The result is a situation like the one the United States is currently facing, in which the herd immunity of the community is not sufficient to stop the chain of infection.

ADVERTISEMENT

James Cherry, an infectious disease specialist at the University of California, Los Angeles, told The New York Times, the current outbreak is “100 percent connected” to the anti-vaccination movement.

“It wouldn’t have happened otherwise — it wouldn’t have gone anywhere” had the communities in which these children lived had herd immunity.

“There are some pretty dumb people out there,” he added.

As Melinda Gates of the Bill and Melinda Gates Foundation told The Huffington Post, “[w]e take vaccines so for granted in the United States. Women in the developing world know the power of them. They will walk 10 kilometers in the heat with their child and line up to get a vaccine, because they have seen death.”

Americans, she said, have “forgotten what measles deaths look like.”