Frozen supplemental shakes have been linked to a nationwide Listeria outbreak that have led to 38 illnesses and 12 deaths.

A nationwide recall has been issued for frozen nutritional shakes linked to a deadly listeria outbreak, according to the Food and Drug Administration. The shakes were sold to hospitals and long-term care institutions, including nursing homes.

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.

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.

“Listeria is especially harmful to pregnant women, people 65 or older, and people with weakened immune systems,” the CDC wrote on its website. “This is because Listeria is more likely to spread beyond their gut to other parts of their body, resulting in a severe condition known as invasive listeriosis.”

Supplemental shakes have been linked to a deadly listeria outbreak. They were distributed in hospitals and long-term care facilities.

An ongoing listeria outbreak credited with 11 deaths is linked to frozen supplemental shakes. Here’s what you should know: The shakes, sold in 4-ounce cartons under the brands Lyons ReadyCare and Sysco Imperial, were made by Prairie Farms Dairy at its Fort Wayne, Indiana, facility.

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.

In the outbreak, 38 people were infected across 21 states, including Pennsylvania, the FDA said. Most of them lived in long-term care facilities or were hospitalized prior to getting sick.