Michigan’s North Bay Produce announced a voluntary recall of six apple varieties after tests found listeria bacteria in the produce. (CNN) A Michigan produce company has recalled nearly 2,300 cases of fresh apples that could be contaminated with listeria. North Bay Produce said the recall affects branded bags of Red Delicious, McIntosh, Honeycrisp, Fuji, Jonathan and Jonamac apples and in non-branded white and plastic bags. The varieties were shipped between October 16 and 21 to Florida, Illinois, Kentucky, Louisiana, Michigan, North Carolina, Texas and Wisconsin. The company found listeria monocytogenes in the produce after it had shipped, though no consumers had fallen ill, it said. Out of caution, consumers are encouraged to discard or return any apples purchased after October 16, North Bay Produce said. The listeria bacteria primarily infects pregnant women, older adults and newborns, the Centers for Disease Control and Prevention said. Its symptoms are similar to other food-borne illnesses, with fever and diarrhea, but in severe cases, it can cause miscarriages or stillbirths in pregnant women.