What is listeria? Everything you need to know

This illustration depicts a three-dimensional (3D) computer-generated image of a grouping of Listeria monocytogenes bacteria. The artistic recreation was based upon scanning electron microscopic (SEM) imagery.

(CNN)Listeria is back in the news again after packages of butternut squash, cauliflower, zucchini and butternut squash based vegetable bowl products from brands Trader Joe's, Green Giant and Signature Farms were recalled.

The manufacturer of the products, Growers Express, voluntarily recalled the products after concerns about a possible contamination of the potentially fatal bacteria Listeria monocytogenes.
"Listeria is an organism that can cause serious and sometimes fatal infections in young children, frail or elderly