An outbreak of listeria infections linked with frozen supplemental shakes has made at least 38 people ill in 21 states, with 37 hospitalizations and 11 deaths, the US Food and Drug Administration said Friday.

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

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.