The traffic data indicate that the cyclospora outbreak is damaging Taco Bell, which in recent years has been the main growth engine for its parent, Yum! Brands Inc. The chain also saw lower visitor numbers in the four days before July 17 and consistently underperformed the fast‑food average during that period, Placer.ai reported.
The negative reports have also weighed on Yum shares. On Monday, Yum stock declined 0.4%, marking its sixth straight drop.
Taco Bell did not reply to a request for comment.
On Monday afternoon, CEO Sean Tresvant shared a LinkedIn post in which he said the company will be open "about what we know and what we are doing next." Tresvant wrote, "We aren't entitled to your loyalty," and added that the chain is "asking the hard questions and doing the work to help build a stronger food system."
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Taco Bell has taken the voluntary step of pulling all U.S. lettuce that came from Taylor Farms, a major producer in the country. The illness, cyclosporiasis - a gastrointestinal condition resulting from swallowing a tiny parasite - was linked by health authorities to lettuce served at Taco Bell locations.
On Saturday, the FDA announced it had found a positive test connecting cyclospora to Taylor Farms lettuce that was not part of an earlier recall, hinting that the problem could grow. However, by Sunday evening, the agency stated that after rechecking the sample, it determined the initial positive result was incorrect. Health officials are now using alternative methods to investigate the outbreak and are continuing to probe Taylor Farms products.
The impact of the outbreak is also being felt across the wider restaurant sector.
Chipotle said it is closely monitoring the outbreak and does not believe its ingredients are involved. Panera chose not to comment, and Chopt did not reply to an inquiry.
Sweetgreen Inc.'s traffic also fell short of the fast‑casual average, though by a smaller margin. The salad chain has stated it is not linked to the outbreak and does not serve iceberg lettuce. Sweetgreen's stock has been volatile, losing over 20% between July 10 and the end of Monday's trading. Sweetgreen did not reply to an inquiry.
The cyclospora outbreak has affected consumers across the country, with the CDC reporting cases in over 30 states. Michigan has been hardest hit, logging 6,148 illnesses and 102 hospitalizations - though state figures usually trail the national totals. Taco Bell's voluntary removal of Taylor Farms lettuce and the CEO's public reassurances are part of the chain's efforts to contain the fallout and rebuild trust.
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