A sign explains why shelves sit empty of Blue Bell ice cream at a grocery store in Dallas, Tuesday, April 21, 2015. Texas-based Blue Bell Creameries issued a voluntary recall Monday, April 20, 2015, for all of its products on the market after two samples of chocolate chip cookie dough ice cream tested positive for Listeriosis. (AP Photo/LM Otero)

(Bloomberg) — Blue Bell Creameries Inc., working to contain the spread of listeria after three people died from the bacterial disease, expanded a product recall to include everything it makes.

Following an earlier recall of some ice cream, listeria has been found in several different places and plants, the Brenham, Texas-based company said. The affected products — including ice cream, frozen yogurt and other snacks — were distributed to retail outlets in 23 U.S. states, including California, Texas, Florida and Illinois, as well as international locations. The recall includes 8 million gallons of ice cream and other products, the company said.

“At this point, we cannot say with certainty how listeria was introduced to our facilities and so we have taken this unprecedented step,” Chief Executive Officer Paul Kruse said in a statement on the family-owned company’s website. “We are heartbroken about this situation.”

The decision was made after the company’s sampling program showed that chocolate chip cookie dough ice cream manufactured March 17 and March 27 contained the bacteria. Blue Bell has now received several positive tests for listeria in different places and plants.

Three people died after eating tainted Blue Bell ice cream at a Kansas hospital, and seven others from Kansas, Arizona, Oklahoma and Texas have been infected, according to the Centers for Disease Control and Prevention. The CDC and the Food and Drug Administration are investigating the outbreak.

Food contamination

Listeria is a serious infection, usually caused by eating food contaminated with the listeria monocytogenes bacterium. The bacteria is found in soil and water and can be carried by some animals and transferred to meat and dairy products, according to the U.S. Department of Health and Human Services.

Unlike many other bacteria, listeria can grow in cold temperatures and can only be killed by cooking or pasteurizing. Some of the most at-risk foods include deli meats, raw milk and other dairy products, soft cheese, and sprouts. The disease primarily affects older people, pregnant women, newborns or adults with weakened immune systems, according to the CDC.

Symptoms include fever and muscle aches, sometimes preceded by diarrhea or other gastrointestinal symptoms. Infection can lead to miscarriage or stillbirth in pregnant women, the CDC said.

Blue Bell isn’t the only company recalling products over listeria fears. Sabra Dipping Co. said this month it would call back 30,000 cases of hummus after a sample tested positive for the bacteria in Michigan. In that case, there were no immediate reports of illness.

Blue Bell’s Kruse said his company is now sanitizing equipment and expanding the number of times it swabs and tests its plants by 800 percent.

“We continue to work with our team of experts to eliminate this problem,” he said.

–With assistance from Anna Edney in Washington.

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