Vaccines are one of the most cost-effective ways of avoiding disease. They're also medically proven to work, but the World Health Organization (WHO) says people are increasingly reluctant to use them. 

A growing complacency towards vaccinating is threatening to reverse the progress made in tackling vaccine-preventable diseases. 

"I educate people on all their options and believe people should make the right choice for themselves," said Cara France, who didn't vaccinate her kids but supports others that do.

TRTWorld'sSally Ayhan reports from Oregon, the United States.