Purchase consideration has also plummeted. About 13 percent of respondents said they would consider Chipotle the next time they ate at a restaurant, its lowest level since February 2014. Since the year began, YouGov interviewed 25,000 adults about Chipotle for its surveys.
Health officials first linked Chipotle to an E. coli outbreak on October 31. Since then, the outbreak, which has sickened 52 people, has widened to nine states. Chipotle's problems worsened when a separate norovirus outbreak at a Boston Chipotle earlier this month sickened 141 Boston College students who recently ate at restaurant.
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"I think it's going to be a while before consumers shake this off and get it out of their mind," said YouGov BrandIndex CEO Ted Marzilli, in a phone interview.
"When two happen so close together, it does have a magnification impact," he added.
In an email, Chipotle spokesman Chris Arnold said of the YouGov results: "Under the circumstances, I don't think these results are surprising. We have been working hard to put in place new plans and programs that will establish Chipotle as a leader in food safety, in much the same way we have established the company as a leader in using the very best ingredients we can get. We are just starting to communicate those new plans to customers, and will continue to do that in the coming weeks and months, and believe that heightened understanding of those changes will help to strengthen consumer perceptions in us again."
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To get the buzz score, YouGov asks respondents, "If you've heard anything about the brand in the last two weeks, through advertising, news or word of mouth, was it positive or negative?" Scores range from 100 to -100 with a score of 100 indicating all positive sentiment, 0 meaning neutral and -100 indicating all negative sentiment.
Consumer perception isn't the only metric declining for the restaurant. Its stock has plunged 13 percent since the E. coli outbreak came to light, while its daily same restaurant sales dropped as much as 22 percent in the wake of the crisis.