Health officials in Iowa and Nebraska on Tuesday tagged prepackaged salad mix as the source for an outbreak of parasite-borne food poisoning in those states even as federal officials worked to see if the conclusion applies elsewhere as well.
Iowa's top food inspector, Steven Mandernach, said that bagged salad was behind the cyclospora outbreak that has sickened at least 143 people in that state and another 78 in Nebraska. Overall, at least 372 people in 15 states have been sickened by the rare parasite since June.
"The evidence points to a salad mix containing iceberg and romaine lettuce, as well as carrots and red cabbage as the source of the outbreak reported in Iowa and Nebraska," said Mandernach, chief of the Food and Consumer Safety Bureau of the Iowa Department of Inspections and Appeals. "Iowans should continue eating salads as the implicated prepackaged mix is no longer in the state's food supply chain."
Nebraska officials also confirmed the source, a spokeswoman said, but neither state would name the brand or the producer of the bagged salad mix -- and they would not say whether it was an imported or domestic product.
But it wasn't yet clear whether the packaged salad was linked to other infections in other states, officials with the Food and Drug Administration and the Centers for Disease Control and Prevention said. At least 21 people have been hospitalized in connection with the outbreak.
"FDA is following the strongest leads provided by the states and has prioritized ingredients of the salad mix identified by Iowa for traceback investigation, but is following other leads as well," agency officials said in a statement Tuesday.
CDC officials said they would continue to work with federal, state and local partners "to determine whether this conclusion applies to the increase in cases of cyclosporiasis in other states." It is not yet clear whether the cases reported in the various states are all part of the same outbreak, the agencies added.
Iowa investigators found that the salad mix from a single source was a common exposure in 80 percent of the cases, officials said. In Nebraska, 85 percent of the cases had a link prepackaged salad mix, said Leah Bucco-White, a state spokeswoman. Officials would not say why they're withholding the brand of the salad, who made it and where it's sold.
Gathering the information was challenging because most of the sick people ate the salad mix during the past several weeks and by the time the parasitic illness was identified, most of the product was no longer on store shelves, Iowa officials said. In addition, it can take a week or more after eating contaminated foods for people to develop symptoms of cyclospora infection.
Cyclospora is a rare parasite typically spread by feces in contaminated food or water. It causes lingering diarrhea and other flu-like symptoms. It can be treated with common antibiotics, but the test to confirm cyclospora infection isn't commonly performed and must be specially requested.
Iowa officials said they would continue working with other states, the FDA and the CDC as the investigation continues. Health departments reporting illnesses include those in Iowa, Nebraska, Texas, Wisconsin, Arkansas, Connecticut, Florida, Georgia, Illinois, Kansas, Minnesota, Missouri, New Jersey, New York, New York City and Ohio.