Chipotle Mexican Grill stock fell about 3% Thursday, extending its sharp decline earlier in the week, after federal health officials linked a multistate Salmonella outbreak to jalapeño peppers served at the burrito chain and other Mexican-style restaurants.
Shares closed nearly 10% lower Tuesday when the outbreak's possible connection to Chipotle was first reported.
The Centers for Disease Control and Prevention said 345 people in 27 states have been infected with the Salmonella Javiana strain. Thirty-six people were hospitalized, and no deaths have been reported.
The CDC and Food and Drug Administration traced the peppers to a grower in Sinaloa, Mexico, and distributor Coast Citrus Distributors. Of 191 patients interviewed, 93% said they had eaten at a Mexican-style restaurant before becoming ill, including Chipotle Mexican Grill and QDOBA.
Coast Citrus agreed to recall the affected peppers. Chipotle began switching suppliers at affected restaurants on July 20, while QDOBA stopped serving jalapeños on July 28.
Regulators said neither chain currently poses an ongoing risk to customers. The FDA said the distributor primarily served restaurants, wholesalers, and food-service companies. It did not appear to supply grocery stores directly, the agency said.
Even though Chipotle has moved fast to remove the affected jalapeños, investors remain concerned about lost traffic and echoes of the chain's food-safety crisis a decade ago.
For the restaurant industry, the immediate financial effect may remain limited because regulators identified the supplier, the affected product was removed, and the latest reported illness began more than two weeks ago.
"We do not believe it indicates any breakdown in Chipotle's restaurant-level health and safety protocols," wrote William Blair analyst Sharon Zackfia in a Thursday note.
The larger risk is reputational: the outbreak comes amid heightened concern about food safety following a separate cyclospora outbreak linked to lettuce served at Taco Bell.
That could make diners more cautious and pressure traffic across fast-casual and Mexican-style chains already contending with inflation and weaker visits from lower-income consumers.
Chipotle had already experienced a roughly 200-basis-point drag on its sales trends in the second half of July following concerns about cyclospora -- even though the company has made clear that it does not serve iceberg lettuce.
Even if the Salmonella cases prove to be an isolated incident, Zackfia said the firm's same-store sales could see as much as a mid- to high-single-digit decline in the month of August, followed by a rebound in September.
She noted that during the E. coli outbreak at Chipotle that began in late October 2015, comparable sales deteriorated about 13 percentage points between October and November.
Still, the analyst reiterated her belief in Chipotle's multiple growth drivers for the long term, including menu innovation, restrained price hikes, the relaunch of its rewards program, the planned rollout of catering, and improved marketing, which are poised to benefit the company in 2027 and beyond.
"History has repeatedly shown that the sales impact of foodborne illness tends to be fleeting for restaurants," she wrote.