April 24 (UPI) -- Twenty-one percent of U.S. ice cream facilities evaluated by the Food and Drug Administration tested positive for harmful pathogens such as listeria, a report released Wednesday indicated.
The agency inspected 89 facilities in 2016 and 2017, after some 16 recalls over the course of the three previous years.
The FDA said it conducted the testing to determine what kind of harmful bacteria may be present in such facilities and whether the companies were correctly implementing food safety programs. Officials evaluated the manufacturing processes and sanitation methods, but not the finished products. All but one samples came from areas of the plants that don't come into contact with food.
Of the 89 establishments tested, the FDA detected listeria monocytogenes at 19 facilities and salmonella at one.
"These activities help the FDA gather data and information necessary to develop prevention-based systems and, when contamination does occur, to respond swiftly to these hazards," said Frank Yiannis, the FDA's deputy commissioner for food policy and response.
The results of the testing resulted in three recalls and the implementation of safety plans to prevent future contaminations.
In addition to the contaminations detected, the FDA found what it called "objectionable" conditions or practices at 45 of the facilities.
The International Dairy Foods Association said that since the FDA testing took place, "significant changes" have occurred industry-wide to prevent contaminations.
"Plants have strengthened their food safety programs to seek out and eliminate harmful bacteria like [listeria monocytogenes] and salmonella wherever they are found in ice cream production environments," said a statement from Matt Herrick, IDFA senior vice president of executive and strategic communications.
"IDFA has worked closely with the industry to ensure awareness of food safety risks and provide all information and resources necessary for the ice cream industry to continue to enhance their food safety programs and keep ice cream a safe, delicious treat."
Of the 16 recalls that took place between 2013 and 2015, perhaps the largest was with Texas ice cream manufacturer Blue Bell Creamery. Products from four Blue Bell factories contaminated with listeria sickened 10 people between January 2010 and January 2015, with all 10 being hospitalized and three deaths as a result.
Invesigators found that several Blue Bell products served at hospitals -- and one product purchased at a store -- were the cause of the outbreak, leading the company to shut down its factories in Brenham, Texas, Broken Arrow, Okla., and Sylacauga, Ala.
Listeriosis can cause fever, muscle aches, headaches, stiff neck, confusion, loss of balance, convulsions, diarrhea and gastrointestinal symptoms. In pregnant women, the infection can cause early delivery or miscarriage.
Salmonella, meanwhile, is a bacterial infection that can cause fever, diarrhea, nausea, vomiting and abdominal pain. In serious cases, the disease can cause arterial infections, endocarditis and arthritis.