Frozen nutritional shakes given to hospital patients and long-term care residents have been recalled after they were linked to 11 deaths and dozens of serious illnesses — with the outbreak dating

A listeria outbreak linked to frozen nutritional milkshakes is to blame for 12 deaths and dozens of hospitalizations, the U.S. Food and Drug Administration confirmed Monday following an investigation that spanned years.

Frozen shakes distributed in long-term facilities around the United States have been recalled due to potential listeria contamination. Lyons Magnus announced Feb. 22 that it had issued a recall for 4 oz. Lyons ReadyCare and Sysco Imperial Frozen Supplemental Shakes, which were manufactured by Prairie Farms Dairy, Inc.