A mid-July contamination of salads sold at McDonald's restaurants have now caused over 500 people to become ill.

WGRZ reports, "The illnesses have been linked to salad mix contaminated with the Cyclospora parasite, which is spread through fecal matter."

The Food and Drug Administration reports 507 confirmed cases of illness, with twenty-four people hospitalized. "The cases were reported by 15 states and New York City," according to the FDA. "The investigation is ongoing and the FDA is currently reviewing distribution and supplier information for romaine and carrots."