Coli outbreak appears to be over, CDC says

The new cases prompted a downgrade of Chipotle shares to neutral from overweight at J.P. Morgan on Tuesday.

The CDC said it is working to determine the cause of the latest outbreak, but said the geographic diversity in the cases suggests they do not share a common source. Dr. Ian Williams, chief of the CDC’s Outbreak Response & Prevention Branch, believes that this fact, as well as the geographic distance and time difference, could point to a completely new, unrelated outbreak. The investigations are ongoing.

Chipotle Mexican Grill founder, co-CEO, and chairman Steve Ells recently expressed his apology and vowed the restaurant as the safest place to eat after food poisoning issues.

All five people said they ate at a Chipotle in the week before they got sick, according to the CDC. The agency warns it could take some time before singling what food contains the toxic E.coli strain.

And some analysts have speculated that customers may abandon Chipotle in favor of rival Qdoba, which is owned by Jack in the Box (JACK), as well as other so-called fast casual chains like Panera(PNRA) and Zoe’s Kitchen (ZOES).

The development is the latest bad news for Chipotle Mexican Grill Inc., which saw its sales plummet after the emergence of the larger E. coli outbreak that has sickened 53 people in nine states. “The investigation has not identified what specific food is linked to illness”. Spokesman Chris Arnold said in an email Monday that the chain is in the process of implementing its new programs, which include increased testing of ingredients and food safety training for workers. “The CDC would not say how likely or unlikely it is that all the cases with both DNA fingerprints are linked but said it is performing tests to make that determination and hopes to know in a few weeks”, CNN reports. That type, so-called non-0157 STEC infections, tends to be less severe than the 0157 strain, which killed four children in a 1993 Jack in the Box outbreak.

Chipotle fell 3.6 percent to 521.71 in the stock market Monday, Investors.com reported.