Here’s the thing with stocking your restaurant with fresh, additive-free ingredients: processing food and adding things like preservatives has an actual purpose, and that purpose is to eliminate or slowt he growth of food-borne pathogens. While their fresh-ingredients stance is an important part of Chipotle’s marketing, it’s also a handy way for nasty food-borne pathogens to sneak in.

Now there’s a total of 37 people who have become ill from the outbreak of E. coli linked to Chipotle restaurants in the Seattle and Portland metropolitan areas.

Chipotle has had three different outbreaks in the last few months: illnesses in California were traced to norovirus of unknown origin, and a Salmonella outbreak in Minnesota linked to tomatoes that were served at 22 different restaurants. These incidents aren’t connected to each other, but combined they

Restaurants in the affected areas are performing deep-cleaning, according to a press release from Chipotle. While there are 43 restaurants closed, only eight have illnesses linked to them. That could change, though, since E. coli can incubate for a long time before making you sick.

Chipotle says that they are also cooperating with health authorities, and on their part are also testing every batch of ingredients in the area before tossing them out and starting over with new ingredients when the restaurants re-open.

If you’ve eaten at a Chipotle in the month of October and experience bloody diarrhea and vomiting, public health authorities want you to visit a health care provider and mention this specific outbreak, so your provider can take samples and submit them to the authorities to verify that your illness was part of the outbreak. The majority of people who are sick with this strain of E. coli report eating at a local Chipotle restaurant, but not all of them.

Oregon cases of E. coli linked to Chipotle now at 12 [Oregon Health Authority]

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