Wegmans Food Markets recalled frozen 12 oz bags of Wegmans Organic Food You Feel Good About Just Picked Spinach over the weekend.

The recalled bags have “best used by” dates of January 26, 2017 and February 2, 2017, according to the announcement from Wegmans which also includes the UPC code from the bags in question.

According to the grocery chain, supplier Twin City Foods notified Wegmans that these packages may have become contaminated with Listeria monocytogenes, a bacteria that may cause Listeriosis.

The infection primarily affects older adults, pregnant women, newborns, and adults with weakened immune systems, according to the CDC. Symptoms can include fever, muscle aches, diarrhea or other gastrointestinal symptoms.