Fresh Express Sunflower Crisp Chopped Salad Kits from the U.S. (left) and Canada. ( Courtesy FDA/CFIA )

Federal health authorities in the U.S. and Canada are advising consumers not to eat a Fresh Express chopped salad kit, linking it to eight E. coli O157:H7 cases in the U.S. and 16 in Canada.

The outbreak strain is different from the one in another current investigation, first announced Nov. 22 by the Food and Drug Administration, naming romaine lettuce from the Salinas, Calif., area as the source. In that outbreak, more than 100 cases in the U.S. have been reported.

The FDA said the new outbreak may have included romaine and other ingredients from a region other than Salinas.

The Fresh Express brand Sunflower Crisp Chopped Salad Kits are the likely source of the outbreaks, according to the Food and Drug Administration and Canadian Food Inspection Agency. The Canada agency has recalled the salads sold at retailers in six provinces. As of Dec. 10, Fresh Express has not recalled the salad, but the FDA is advising the salads not to be sold and consumers not to eat them.

In the U.S., six of the patients reported “eating or maybe eating” the Fresh Express Sunflower Crisp Chopped Salad.

The CFIA announced the recall on Dec. 8 and the FDA posted its advisory on Dec. 9.

The salad kits have a Universal Product Code of 0 71279 30906 4, including all packages with “best before” dates of 07DEC19 (Dec. 7), lot codes beginning with “Z” and indicating Salinas as a source of the romaine lettuce.

The FDA, Centers for Disease Control and Prevention, CFIA and Public Health Agency of Canada are investigating the cases, according to the FDA.

The CFIA said the salad kit labels indicate Salinas is the growing region of the ingredients.

"Preliminary information indicates that the romaine lettuce in the salad kits eaten by some sick people may have contained romaine from the Salinas growing region, though the romaine and other ingredients in the kit may have come from another growing region as well," according to the FDA notice.

“Authorities are investigating the source of the ingredients in the kits and are trying to determine which ingredient may have been contaminated,” according to the FDA.

The kits contain green cabbage, romaine, kale, red cabbage and carrots, according to the label.

The eight cases in the U.S. are in Minnesota (4), North Dakota (1) and Wisconsin (3).

In the U.S., cases were first reported on Nov. 5, and the last one was Nov. 15. The Canadians became ill Nov. 5-Nov. 22.

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