People in at least another five states have been sickened by tainted McDonald's salads.
Health officials in Missouri, Wisconsin, Nebraska, South Dakota and Minnesota all report they now have cases of people infected by the Cyclospora parasite that they believe came from having eaten lettuce in salads at McDonald's. But the numbers, so far, are limited. Each of the states has two cases, except for Missouri, which has seven, and Minnesota, which has three.
The new states join Iowa and McDonald's home state of Illinois – the chain is based in Chicago – who reported their outbreaks Thursday. So far, there are 16 cases in Iowa and 29 in Illinois.
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The multi-state total is 61.
Cyclosporiasis is a non-fatal infection and the most common symptom is watery diarrhea, according to the Centers for Disease Control. People fall ill an average of seven days after eating the food contaminated with fecal matter.
McDonald's said that until it can switch to another lettuce-blend supplier, the company was voluntarily halting sales of salads "out of an abundance of caution" at distribution centers and an estimated 3,000 restaurants. They're primarily in the Midwest -- the seven impacted states along with Indiana, Kentucky, Michigan, Montana, North Dakota, Ohio and West Virginia.
"McDonald’s is committed to the highest standards of food safety and quality control," the company said in a statement. "We are closely monitoring this situation and cooperating with state and federal public health authorities as they further investigate."
Officials in Indiana, Michigan, Montana and West Virginia said they have no reported cases of cyclosporiasis related to the McDonald's salads. Public-health officials in the other four states couldn't immediately be reached for comment.
The Cyclospora parasite is also what sickened more than 200 people in the Midwest who ate contaminated Del Monte vegetable trays earlier this month.
Other symptoms of cyclosporiasis include loss of appetite, weight loss, cramps, bloating, gassiness, nausea and fatigue, the CDC said. Less common are vomiting and a low-grade fever. The illness is treated with antibiotics.
"Some water had to become contaminated and then used to irrigate the crops that become salad," said Martin Bucknavage, a Pennsylvania State University food safety expert. "These spores get into the water and survive for long periods of time. It could some from someplace upstream."
This isn't the first time this summer Americans have gotten ill from greens. E. coli-tainted romaine lettuce from the Yuma, Ariz., growing region sickened 210 people in 36 states, according to CDC. Ninety-six victims were hospitalized, including 27 who developed kidney failure.
McDonald's stock closed at $158.51, down 61 cents or 0.38 percent, on Friday.