395 People in 15 States Infected in McDonald’s Salad Outbreak

A display for McDonald's Asian Salad in a McDonald's restaurant in Oakbrook, Illinois, on June 25 2006. (Tim Boyle/Getty Images)

McDonald’s salads have infected 395 people with Cyclospora in 15 states as of Aug. 2.

The Food and Drug Administration (FDA), Centers for Disease Control and Prevention (CDC) and government officials are investigating the outbreak of Cyclosporiasis, an intestinal illness caused by a microscopic parasite.

Infected people shed unsporulated (non-infective; immature) Cyclospora cayetanensis oocysts in their stool; immature oocysts usually require at least 1–2 weeks under favorable laboratory conditions to sporulate and become infective . An unsporulated oocyst, with undifferentiated cytoplasm, is shown (far left), next to a sporulating oocyst that contains two immature sporocysts (A). An oocyst that was mechanically ruptured has released one of its two sporocysts (B). One free sporocyst is shown as well as two free sporozoites, the infective stage of the parasite (C). (Credit: CDC/DPDx)

McDonald’s released a statement on July 13 saying they had been in contact with public health officials notifying them about an increase in Cyclospora infections in Iowa and Illinois. The CDC received reports of people feeling ill after eating at a McDonald’s restaurant in Minnesota, Missouri, Nebraska, South Dakota, and Wisconsin. In response, McDonald’s has stopped selling salads in 3,000 U.S. restaurants until they can replace their lettuce supplier.

On July 26, the FDA’s investigation of Fresh Express, a salad mix retailer, they found Cyclospora in an unused package of salad mix containing romaine lettuce and carrots that was distributed to McDonald’s. The expiration date on the salad, July 19, had already passed.

Concerned that the romaine lettuce and carrots are still on the market, the FDA instructed Fresh Express to give a report. Fresh Express reported that the positive sample of salads containing romaine lettuce was not for direct retail sale as they have expired already and the carrots used in the salad mix were only distributed to McDonald’s restaurants.

Fresh Express used recall procedures to inform companies about the romaine lettuce and McDonald’s has stopped selling salads at impacted restaurants in the following states: IL, IA, IN, WI, MI, OH, MN, NE, SD, MT, ND, KY, WV, and MO.