A massive recall has brought more attention and put more pressure on a century-old Texas ice cream company that has been searching to discover how its products became linked to a deadly string of listeria cases.
Texas-based Blue Bell Creameries said Tuesday, a day after recalling all its products, that it is getting closer to pinpointing the cause of the contamination. Amid those efforts, the Centers for Disease Control and Prevention said Tuesday that the number of illnesses linked to the company's products has increased to 10.
"As each day passes, we are getting closer and closer to figuring out how this listeria was introduced into our facilities. ... It's a matter of doing the work and not making excuses," said Blue Bell spokesman Joe Robertson. He said consumers "are our No. 1 concern."
The company said a team of microbiologists it hired is working with federal officials at its four facilities in Texas, Oklahoma and Alabama to identify the cause of the listeria.
Blue Bell is also expanding its cleaning and sanitization system, beefing up its employee training, expanding its swabbing system by 800 percent to include more surfaces and is sending daily samples to a microbiology laboratory for testing.
Blue Bell, which has been in business for 108 years, also said that under a new policy, it will test all products produced at its facilities before sending them out to retailers.
Employees at Dallas-area Kroger, Minyard and Tom Thumb stores confirmed that they were told to remove all products on Monday night.
The United supermarket chain, which includes Albertson's and Market Street, said in a statement it would offer refunds for customers who return Blue Bell items.
Listeria primarily affects pregnant women and their newborns, older adults and people with immune systems weakened by cancer, cancer treatments, or other serious conditions. Two more illnesses have now been confirmed in Oklahoma and Arizona.
The CDC had previously reported eight illnesses in Kansas and Texas, including three deaths in Kansas linked to ice cream contaminated with listeria. Those sickened fell ill between January 2010 and January 2015.
Dr. Robert Tauxe of the CDC said the cause of an outbreak is almost always dirty equipment. Listeria occurs naturally in soil and water, and it could be tracked into a plant on an employee's shoes, introduced through animal feces or spread by employees not washing their hands. It can grow at room temperature or in cold temperatures. It can survive forever if it's not cleaned up.
Tauxe said this outbreak is unusual because it's lasted so long and because it's in ice cream, which hasn't usually been associated with listeria. The pathogen is more commonly found in processed meats, unpasteurized cheeses and unpasteurized milk.
Listeria has also been found in fruit in recent years -- listeria in cantaloupes was linked to 30 deaths in a 2011 outbreak. More recently, Sabra Dipping Co. announced a recall of 30,000 cases of its Classic Hummus, also due to possible listeria contamination. No illnesses have been linked to that recall.
Blue Bell said its recall, involving about 8 million gallons of ice cream products, will take two to three weeks to complete and that it will be at least that long before products are back in stores. The recall includes ice cream, frozen yogurt, sherbet and frozen snacks distributed in 23 states and abroad.
The company had 6.4 percent of the U.S. ice cream market in 2014, with $881.8 million in sales, ranking it third in the country, according to market-research firm Euromonitor. Robertson said Blue Bell is not laying off any of its 3,800 employees, as all of them will be needed to help with the recall.
Blue Bell is the best-selling ice cream in Texas, with more than half of the state's market share.
Matthew D'Uva, president of the trade organization the Society of Consumer Affairs Professionals in Business, said while Blue Bell's preference would be finding the source of the listeria as quickly as possible, "you also want to get it right."
"The consumer will look at the entire process and positively judge a company who is getting information to them correctly," he said.
The illness was initially tracked to a production line in Brenham, Texas, the company's headquarters, triggering an initial recall of some products. Listeria was later linked to a facility in Broken Arrow, Oklahoma, which has been shut down.
Monday's recall was initiated after samples from another production line in Brenham tested positive. While no samples from a plant in Sylacauga, Alabama, have tested positive, products produced there have also been recalled. The company also has 62 distribution centers.
Monday's recall extends to retail outlets in Alabama, Arizona, Arkansas, Colorado, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Mississippi, Missouri, Nevada, New Mexico, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas, Virginia, Wyoming and international locations.
The Associated Press contributed to this report.