Federal health officials say they have confirmed more than 500 cases of people who became sick with an intestinal illness after eating McDonald’s salads.
The illnesses reported earlier this year are linked to the cyclospora parasite, which can cause diarrhoea, intestinal pain, nausea or tiredness.
The Food and Drug Administration said on Friday that 507 cases have been confirmed in 15 states and New York City.
McDonald’s stopped the sale of salads at 3,000 restaurants last month until it could find a different supplier.
The FDA says it is still investigating the supplier of romaine lettuce and carrots.
States with cases include: Iowa, Indiana, Michigan, Minnesota, Missouri, Nebraska, Ohio, South Dakota and Wisconsin. Officials also said people sickened in Connecticut, Florida, New York City, Tennessee, and Virginia had travelled in Illinois and Kentucky.
The patients in Connecticut, New York, Tennessee and Virginia all purchased their salads while they were visiting Illinois and the Florida patient purchased the suspect salad while in Kentucky, according to the Center for Disease Control.