A California farm is recalling a vegetable mix believed to be the source of E.coli in Costco chicken salad that has been linked to an outbreak that has sickened 19 people in seven states, the Food and Drug Administration said Thursday.

Taylor Farms Pacific Inc. of Tracy, California, has recalled a mix of diced celery and onion used in Costco chicken salad and other foods containing celery "out of an abundance of caution," the FDA said in a statement.

The foods range from Thai-style salads to packaged dinners and wraps, and they are sold at Costco, Target, Starbucks and many other outlets, the FDA said.

Costco says it uses one supplier for those vegetables in the chicken salad sold in all its U.S. stores.

A message left Thursday with Taylor Farms was not immediately returned.

Costco, based in Issaquah, Washington, pulled the chicken salad off store shelves nationwide, posted signs in its stores and provided detailed purchase logs to the U.S. Centers for Disease Control and Prevention to help it track who bought the product and where the salad ingredients came from.

Six people got sick in Montana, five in Utah, four in Colorado, and one each in California, Missouri, Virginia and Washington state. The illness reports began on Oct. 6 and involved people from age 5 to 84, the CDC said.

Health officials urged people who bought chicken salad at any U.S. Costco store on or before Nov. 20 to throw it away, even if no one has gotten sick.

The strain of Shiga toxin-producing E. coli can be life-threatening, but no deaths have been reported. Five people have been hospitalized, including two with kidney failure.

Symptoms of E. coli infection include diarrhea, abdominal cramps, nausea and vomiting. The incubation period is three to seven days from the time of exposure.

The number of people sickened in the outbreak will likely grow over the next few weeks, even though the product has been removed from store shelves, the CDC said Wednesday.

Health officials urge anyone with the symptoms, especially people who have eaten Costco chicken salad, to go to their doctor.