Elderly people, pregnant women, and young babies can also be at risk of serious complications from the infection.
Invulnerable groups, listeria could spread through the body and attack the brain, or cause miscarriages in expectant mothers.
The FDA said scientists who studied skin samples from 1,615 avocados, found the overall prevalence of Listeria monocytogenes to be 17.73 percent.
The researchers also found that refrigerating the avocados in water only allowed the bacteria to migrate from the outside of the fruit to the inside.