A Washington state-based company is recalling some of its hummus products because they may be contaminated with Listeria monocytogenes. Penny’s Salsa of Auburn, WA initiated a recall of certain hummus products Sunday after two types of the spread tested positive for Listeria, according to the Oregonian. The hummus was sold at QFC locations in Oregon, and was also sold in Washington state, but the retail locations at which it was sold there were unknown as of Sunday. The recalled hummus products are marked with use-by dates of July 13 through August 25, 2013. They are sold under the Penny’s Hummus brand. No illnesses have been linked to the recalled hummus to date. Symptoms of listeriosis (the disease caused by Listeria infection) include fever, muscle aches, headache, stiff neck, confusion, loss of balance and convulsions. Illness can be more serious in older adults and pregnant woman, among whom the condition can lead to stillbirth or miscarriage. Symptoms in pregnant women include fever, fatigue and general aches. If you think you may have contracted listeriosis, contact your healthcare provider or your local health department.