The frozen shakes were served at hospitals and long-term care facilities, sickening 38 people and resulting in 11 deaths in 21 states, according to the FDA.

The FDA announced that a food distributor is recalling all ReadyCare and Sysco Imperial Frozen Supplemental shakes, typically sold to long-term care facilities, over listeria concerns.

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.