Food safety sleuths have still not cracked the E. coli outbreak traced to Chipotle but the lawsuits have started.

A case was filed in federal court in Portland on Friday by the Seattle law firm, Marler Clark, on behalf of a Lake Oswego web developer, Chris Collins.

The 32-year-old came down with severe gastrointestinal symptoms after eating a chicken bowl at the Chipotle restaurant on Centerpoint Drive in Lake Oswego. It is one of five restaurants in the Portland area which were implicated in the outbreak in Oregon. Five other locations were involved in Washington state.

Collins got sick two days after visiting the restaurant on Oct. 23. He later sought medical treatment and has since been recovering at home. The complaint said he's been unable to work since Oct. 29.

A Kelso, Washington woman, a 41-year-old pharmacist, also filed a lawsuit against Chipotle in Washington state earlier this week. She, too, has been out of work.

They both seek unspecified damages, accusing the restaurant of negligence. It may turn out to be a supplier who's at fault.

All of the patients were sickened by a strain of E. coli O26, which can cause kidney failure or worse. Health officials suspect tainted lettuce, tomatoes, salsa or cilantro. They're awaiting lab results on the food from the Food and Drug Administration.

Meanwhile, Oregon added one more case to its tally on Friday, which now stands at 13 sick, including four hospitalized. Washington state health authorities said Friday in a statement they still have 28 cases, including 10 hospitalized.

The Centers for Disease Control and Prevention said Friday it had identified a patient in Minnesota sickened by the strain in the Chipotle outbreak, but a statement said that case did not appear to be related. Minnesota officials are investigating.

Chipotle closed 43 stores in the Portland area and Washington state. Health officials want confirmation that the locations are sanitized and that the food has been destroyed before giving the go-ahead to reopen.

-- Lynne Terry

lterry@oregonian.com; 503-221-8503