(CBS SF) — The recent measles outbreak that has reached 14 states and infected more than 100 people has many wondering how a disease that was considered eradicated in the U.S. 15 years ago is a renewed threat to public health.

It’s reignited the debate behind the anti-vaxxer movement fueled by parents’ skepticism about the safety and usefulness of vaccines.

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So how did it all begin?

The hysteria is largely attributed to now unlicensed British doctor Andrew Wakefield and a now debunked study published in 1998 claiming the measles-mumps-rubella (MMR) vaccine could lead to the onset of autism.

The study of only 12 children was retracted as fraudulent and Wakefield lost his medical license, but the concept became stuck in the public psyche.

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Here’s a timeline of the rise and fall of measles outbreaks and the role the anti-vaccine movement plays:

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