Two hundred twelve people have been infected with an intestinal parasite in four upper Midwest states after reportedly eating pre-packed vegetable trays under the Del Monte Fresh Produce brand, according to the Centers for Disease Control and Prevention. The trays were purchased at various retailers including Kwik Trip or Kwik Star convenience stores.
The outbreak was first tracked by the CDC in mid-June, and is most severe in Wisconsin. As many as 54 cases have also been reported in Minnesota, along with a handful in Iowa and Michigan. Seven victims have been hospitalized, according to the CDC.
A recall was also issued in mid-June for the Del Monte trays, which included baby carrots, broccoli, cauliflower, and dill dip, and were labeled for sale by Jun 17. But the number of infections has grown since then, and the CDC is warning that more cases could still be reported, because the cyclosporiasis infection has a delayed onset for symptoms of roughly one week and can last for weeks. Anyone who might still have a recalled product should dispose of it—washing contaminated produce is not enough to get rid of the pathogen.
Get Data Sheet, Fortune’s technology newsletter.
Cyclosporiasis is caused by Cyclospora cayetanensis, a single-celled protozoa most commonly transmitted on produce contaminated with human fecal matter, particularly from tropical or subtropical regions where the parasite is native. According to the Food and Drug Administration, symptoms of cyclosporiasis include severe diarrhea, stomach cramps, bloating, nausea, and fatigue. Without treatment, the infection can last from as little as a few days to more than a month. Cyclosporiosis is usually not life threatening.
A previous major cyclosporiasis outbreak was reported in 2015, when 546 individuals were infected across 31 states. That outbreak was linked to contaminated cilantro from Mexico, and led to no fatalities.