(CNN) — A Listeria outbreak linked to soft cheeses has caused 24 cases of illness in nine states, including one death and one fetal death, the CDC said Friday. Twenty-one of those who became ill have been hospitalized.
The agency is working with state health officials and the FDA to investigate the outbreak that dates back to August 8, 2010.
The source of the Listeria contamination is still under investigation but most of those who became ill reported eating soft cheese within a month of when they developed symptoms.
This prompted Karoun Dairies, Inc. to announce a voluntary recall and stop production of some of their cheeses on Wednesday. The products that may be contaminated are sold under the brands Karoun, Arz, Gopi, Queso Del Valle, Central Valley Creamery and Yanni. They are vacuum packed in jars or pails and weigh between 5 and 30 ounces, the company said. Recalled products should not be consumed and any restaurants, stores or consumers who have any of these items should return them or throw them away.
The states where illnesses have been reported include California, Colorado, Illinois, Massachusetts, Michigan, New York, Ohio, Tennessee and Washington.
Symptoms of Listeriosis infection include fever, muscle aches, and gastrointestinal illness such as diarrhea. It can also lead to meningitis, it has in three children in this current outbreak. Pregnant women, newborns, older adults and anyone with a weakened immune system are most at risk for infection.
Five pregnant women are among those who have become sick from during this outbreak and one fetal death has been reported. Those who are sick range in age from 1 to 92 and 75% of them are female.
This year alone frozen greenbeans, spinach, hummus, and ice cream have all been recalled due to possible listeria outbreak and Blue Bell Creameries shut down their entire production line while they decontaminated their factories due to an outbreak dating back to 2010.
It’s likely the number of cases is actually greater than 24 because not every case is diagnosed. One more case probably exists for every case they know of, according to Dr. Robet Tauxe, deputy director of the CDC Division of Foodborne, Waterborne and Environmental Diseases.
Listeria can be particularly challenging for food manufacturers to eliminate because it can hide in places like drains or pipes for years, Tauxe said.