More than 500 people have so far become ill in the U.S. multistate outbreak of Cyclospora that led numerous retailers to recall bagged salad products over recent weeks.

The Food and Drug Administration (FDA) said in a July 9 update that as of Wednesday there had been 506 cases of illnesses across eight Midwestern states. There have been 33 hospitalizations and no deaths.

The states with cases are: IA (160), IL (151), KS (5), MN (63), MO (46), NE (48), ND (6), WI (30).

The FDA says traceback investigation is ongoing to determine the cause and source of the outbreak. Salad ingredients (iceberg lettuce, carrots, red cabbage) continue to be items "of interest" in the investigation.

Between June 20 - 25, there were recalls of salad products containing these ingredients. These recalls included products sold at ALDI, Hy-Vee, Jewel-Osco, and Walmart.

FDA’s inspection continues at the Fresh Express production facility in Streamwood, Illinois.

The Public Health Agency of Canada has issued a public health notice regarding an outbreak of Cyclospora infections in Canada. Exposure to certain Fresh Express brand salad products containing iceberg lettuce, carrots, and red cabbage, has been identified as a likely source of the outbreak.