HOUSTON (WHNT) - Listeria bacteria was found in Blue Bell's Oklahoma plant as early as March 2013, according to results released on Thursday by the U.S Food and Drug Administration.
According to the report, there were 16 positive tests of listeria at the Oklahoma plant between March 2013 and January 2015. Despite the positive tests, the company continued to package and sell ice cream.
The report describes tests that suggested a "presumptive positive" for listeria on surfaces like floors and pallets used to store and carry food items.
In Alabama, investigators observed at least two employees wearing soiled clothing while handling food. In Texas, the report says investigators observed condensation dripping into food containers.
The FDA report was released on Thursday following a Freedom of Information Act request by the Houston Chronicle.
Listeria bacteria can cause serious and sometimes fatal infections in young children, the elderly and others with weak immune systems.
Three people in Kansas have died from listeria-tainted Blue Bell products. A total of 10 patients infected with listeria were reported in four states: Arizona (1), Kansas (5), Oklahoma (1), and Texas (3). All ten patients were hospitalized.
The company has collected 8 million gallons of ice cream from retailers and other outlets during the product recall.
The company said they are "committed to a thorough process that will ensure the highest quality and safety of our products for our customers going forward."
All three plants remain closed as the company continues to clean and sanitize the facilities.
"Unfortunately, we do not yet have a firm timeline for when Blue Bell Ice Cream will be back in stores, but we believe at this time that it will be several months at a minimum," Blue Bell CEO and President Paul Kruse said in a statement.
After weeks of gradual recalls, the company recalled all its ice cream, frozen yogurt, sherbet and other frozen treats sold in 23 states dating back to 2010.
The origin of the strain is still unknown, but "the fact that it was the same strain over the last five years suggests it could have lurked somewhere in the factory the whole time," Dr. Robert Tauxe, deputy director of the CDC Division of Foodborne, Waterborne and Environmental Diseases told CNN.
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